remove all debug

typo: fix comment


fix: fix verify flow and precompile cookies


fix: implement requested changes


fix: implement requested changes


fix: implement requested changes


test(auth): add test for MS-PASS


fix: remove pointless return

.github/workflows/tests.yml

@@ -15,8 +15,9 @@ jobs:
     strategy:
       matrix:
         goversion:
-          - "1.17"
+          - "1.20"
-          - "1.16"
+          - "1.19"
+          - "1.18"
     steps:
       - name: Set up Go
         uses: actions/setup-go@v1
@@ -27,4 +28,4 @@ jobs:
       - name: Get dependencies
         run: go get ./...
       - name: Run Unit Tests
-        run: go test -v -cover -race ./...
+        run: go test -modfile=go_test.mod -v -cover -race ./...

.travis.yml

@@ -1,10 +0,0 @@
-language: go
-
-go:
-  - "1.x"
-
-install:
-  - go get ./...
-
-script:
-  - go test -v --short ./...

Makefile

@@ -9,23 +9,32 @@ ${BIN}: ${SRC}
 	go build -o $@ ./cmd/gowebdav
 
 test:
-	go test -v --short ./...
+	go test -modfile=go_test.mod -v -short -cover ./...
 
-api:
+api: .go/bin/godoc2md
 	@sed '/^## API$$/,$$d' -i README.md
 	@echo '## API' >> README.md
-	@godoc2md github.com/studio-b12/gowebdav | sed '/^$$/N;/^\n$$/D' |\
+	@$< github.com/studio-b12/gowebdav | sed '/^$$/N;/^\n$$/D' |\
 	sed '2d' |\
 	sed 's/\/src\/github.com\/studio-b12\/gowebdav\//https:\/\/github.com\/studio-b12\/gowebdav\/blob\/master\//g' |\
 	sed 's/\/src\/target\//https:\/\/github.com\/studio-b12\/gowebdav\/blob\/master\//g' |\
 	sed 's/^#/##/g' >> README.md
 
-check:
+check: .go/bin/gocyclo
 	gofmt -w -s $(SRC)
 	@echo
-	gocyclo -over 15 .
+	.go/bin/gocyclo -over 15 .
 	@echo
-	golint ./...
+	go vet -modfile=go_test.mod ./...
+
+
+.go/bin/godoc2md:
+	@mkdir -p $(@D)
+	@GOPATH="$(CURDIR)/.go" go install github.com/davecheney/godoc2md@latest
+
+.go/bin/gocyclo:
+	@mkdir -p $(@D)
+	@GOPATH="$(CURDIR)/.go" go install github.com/fzipp/gocyclo/cmd/gocyclo@latest
 
 clean:
 	@rm -f ${BIN}

README.md

@@ -1,13 +1,16 @@
 # GoWebDAV
 
-[![Build Status](https://travis-ci.org/studio-b12/gowebdav.svg?branch=master)](https://travis-ci.org/studio-b12/gowebdav)
+[![Unit Tests Status](https://github.com/studio-b12/gowebdav/actions/workflows/tests.yml/badge.svg)](https://github.com/studio-b12/gowebdav/actions/workflows/tests.yml)
+[![Build Artifacts Status](https://github.com/studio-b12/gowebdav/actions/workflows/artifacts.yml/badge.svg)](https://github.com/studio-b12/gowebdav/actions/workflows/artifacts.yml)
 [![GoDoc](https://godoc.org/github.com/studio-b12/gowebdav?status.svg)](https://godoc.org/github.com/studio-b12/gowebdav)
 [![Go Report Card](https://goreportcard.com/badge/github.com/studio-b12/gowebdav)](https://goreportcard.com/report/github.com/studio-b12/gowebdav)
 
-A golang WebDAV client library.
+A pure Golang WebDAV client library that comes with a [reference implementation](https://github.com/studio-b12/gowebdav/tree/master/cmd/gowebdav).
+
+## Features at a glance
+
+Our `gowebdav` library allows to perform following actions on the remote WebDAV server:
 
-## Main features
-`gowebdav` library allows to perform following actions on the remote WebDAV server:
 * [create path](#create-path-on-a-webdav-server)
 * [get files list](#get-files-list)
 * [download file](#download-file-to-byte-array)
@@ -17,6 +20,17 @@ A golang WebDAV client library.
 * [copy file to another location](#copy-file-to-another-location)
 * [delete file](#delete-file)
 
+It also provides an [authentication API](#type-authenticator) that makes it easy to encapsulate and control complex authentication challenges.
+The default implementation negotiates the algorithm based on the user's preferences and the methods offered by the remote server.
+
+Out-of-box authentication support for:
+
+* [BasicAuth](https://en.wikipedia.org/wiki/Basic_access_authentication)
+* [DigestAuth](https://en.wikipedia.org/wiki/Digest_access_authentication)
+* [MS-PASS](https://github.com/studio-b12/gowebdav/pull/70#issuecomment-1421713726)
+* [WIP Kerberos](https://github.com/studio-b12/gowebdav/pull/71#issuecomment-1416465334)
+* [WIP Bearer Token](https://github.com/studio-b12/gowebdav/issues/61)
+
 ## Usage
 
 First of all you should create `Client` instance using `NewClient()` function:
@@ -27,11 +41,13 @@ user := "user"
 password := "password"
 
 c := gowebdav.NewClient(root, user, password)
+c.Connect()
+// kick of your work!
 ```
 
 After you can use this `Client` to perform actions, described below.
 
-**NOTICE:** we will not check errors in examples, to focus you on the `gowebdav` library's code, but you should do it in your code!
+**NOTICE:** We will not check for errors in the examples, to focus you on the `gowebdav` library's code, but you should do it in your code!
 
 ### Create path on a WebDAV server
 ```go
@@ -57,7 +73,7 @@ webdavFilePath := "folder/subfolder/file.txt"
 localFilePath := "/tmp/webdav/file.txt"
 
 bytes, _ := c.Read(webdavFilePath)
-ioutil.WriteFile(localFilePath, bytes, 0644)
+os.WriteFile(localFilePath, bytes, 0644)
 ```
 
 ### Download file via reader
@@ -79,7 +95,7 @@ io.Copy(file, reader)
 webdavFilePath := "folder/subfolder/file.txt"
 localFilePath := "/tmp/webdav/file.txt"
 
-bytes, _ := ioutil.ReadFile(localFilePath)
+bytes, _ := os.ReadFile(localFilePath)
 
 c.Write(webdavFilePath, bytes, 0644)
 ```
@@ -159,42 +175,60 @@ Package gowebdav is a WebDAV client library with a command line tool
 included.
 
 ### <a name="pkg-index">Index</a>
+* [Constants](#pkg-constants)
+* [Variables](#pkg-variables)
 * [func FixSlash(s string) string](#FixSlash)
 * [func FixSlashes(s string) string](#FixSlashes)
+* [func IsErrCode(err error, code int) bool](#IsErrCode)
+* [func IsErrNotFound(err error) bool](#IsErrNotFound)
 * [func Join(path0 string, path1 string) string](#Join)
+* [func NewPathError(op string, path string, statusCode int) error](#NewPathError)
+* [func NewPathErrorErr(op string, path string, err error) error](#NewPathErrorErr)
 * [func PathEscape(path string) string](#PathEscape)
 * [func ReadConfig(uri, netrc string) (string, string)](#ReadConfig)
 * [func String(r io.Reader) string](#String)
+* [type AuthFactory](#AuthFactory)
 * [type Authenticator](#Authenticator)
+  * [func NewDigestAuth(login, secret string, rs *http.Response) (Authenticator, error)](#NewDigestAuth)
+  * [func NewPassportAuth(c *http.Client, user, pw, partnerURL string, header *http.Header) (Authenticator, error)](#NewPassportAuth)
+* [type Authorizer](#Authorizer)
+  * [func NewAutoAuth(login string, secret string) Authorizer](#NewAutoAuth)
+  * [func NewEmptyAuth() Authorizer](#NewEmptyAuth)
+  * [func NewPreemptiveAuth(auth Authenticator) Authorizer](#NewPreemptiveAuth)
 * [type BasicAuth](#BasicAuth)
-  * [func (b *BasicAuth) Authorize(req *http.Request, method string, path string)](#BasicAuth.Authorize)
+  * [func (b *BasicAuth) Authorize(c *http.Client, rq *http.Request, path string) error](#BasicAuth.Authorize)
-  * [func (b *BasicAuth) Pass() string](#BasicAuth.Pass)
+  * [func (b *BasicAuth) Clone() Authenticator](#BasicAuth.Clone)
-  * [func (b *BasicAuth) Type() string](#BasicAuth.Type)
+  * [func (b *BasicAuth) Close() error](#BasicAuth.Close)
-  * [func (b *BasicAuth) User() string](#BasicAuth.User)
+  * [func (b *BasicAuth) String() string](#BasicAuth.String)
+  * [func (b *BasicAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)](#BasicAuth.Verify)
 * [type Client](#Client)
+  * [func NewAuthClient(uri string, auth Authorizer) *Client](#NewAuthClient)
   * [func NewClient(uri, user, pw string) *Client](#NewClient)
   * [func (c *Client) Connect() error](#Client.Connect)
   * [func (c *Client) Copy(oldpath, newpath string, overwrite bool) error](#Client.Copy)
-  * [func (c *Client) Mkdir(path string, _ os.FileMode) error](#Client.Mkdir)
+  * [func (c *Client) Mkdir(path string, _ os.FileMode) (err error)](#Client.Mkdir)
-  * [func (c *Client) MkdirAll(path string, _ os.FileMode) error](#Client.MkdirAll)
+  * [func (c *Client) MkdirAll(path string, _ os.FileMode) (err error)](#Client.MkdirAll)
   * [func (c *Client) Read(path string) ([]byte, error)](#Client.Read)
   * [func (c *Client) ReadDir(path string) ([]os.FileInfo, error)](#Client.ReadDir)
   * [func (c *Client) ReadStream(path string) (io.ReadCloser, error)](#Client.ReadStream)
+  * [func (c *Client) ReadStreamRange(path string, offset, length int64) (io.ReadCloser, error)](#Client.ReadStreamRange)
   * [func (c *Client) Remove(path string) error](#Client.Remove)
   * [func (c *Client) RemoveAll(path string) error](#Client.RemoveAll)
   * [func (c *Client) Rename(oldpath, newpath string, overwrite bool) error](#Client.Rename)
   * [func (c *Client) SetHeader(key, value string)](#Client.SetHeader)
   * [func (c *Client) SetInterceptor(interceptor func(method string, rq *http.Request))](#Client.SetInterceptor)
+  * [func (c *Client) SetJar(jar http.CookieJar)](#Client.SetJar)
   * [func (c *Client) SetTimeout(timeout time.Duration)](#Client.SetTimeout)
   * [func (c *Client) SetTransport(transport http.RoundTripper)](#Client.SetTransport)
   * [func (c *Client) Stat(path string) (os.FileInfo, error)](#Client.Stat)
-  * [func (c *Client) Write(path string, data []byte, _ os.FileMode) error](#Client.Write)
+  * [func (c *Client) Write(path string, data []byte, _ os.FileMode) (err error)](#Client.Write)
-  * [func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) error](#Client.WriteStream)
+  * [func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) (err error)](#Client.WriteStream)
 * [type DigestAuth](#DigestAuth)
-  * [func (d *DigestAuth) Authorize(req *http.Request, method string, path string)](#DigestAuth.Authorize)
+  * [func (d *DigestAuth) Authorize(c *http.Client, rq *http.Request, path string) error](#DigestAuth.Authorize)
-  * [func (d *DigestAuth) Pass() string](#DigestAuth.Pass)
+  * [func (d *DigestAuth) Clone() Authenticator](#DigestAuth.Clone)
-  * [func (d *DigestAuth) Type() string](#DigestAuth.Type)
+  * [func (d *DigestAuth) Close() error](#DigestAuth.Close)
-  * [func (d *DigestAuth) User() string](#DigestAuth.User)
+  * [func (d *DigestAuth) String() string](#DigestAuth.String)
+  * [func (d *DigestAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)](#DigestAuth.Verify)
 * [type File](#File)
   * [func (f File) ContentType() string](#File.ContentType)
   * [func (f File) ETag() string](#File.ETag)
@@ -206,41 +240,86 @@ included.
   * [func (f File) Size() int64](#File.Size)
   * [func (f File) String() string](#File.String)
   * [func (f File) Sys() interface{}](#File.Sys)
-* [type NoAuth](#NoAuth)
+* [type PassportAuth](#PassportAuth)
-  * [func (n *NoAuth) Authorize(req *http.Request, method string, path string)](#NoAuth.Authorize)
+  * [func (p *PassportAuth) Authorize(c *http.Client, rq *http.Request, path string) error](#PassportAuth.Authorize)
-  * [func (n *NoAuth) Pass() string](#NoAuth.Pass)
+  * [func (p *PassportAuth) Clone() Authenticator](#PassportAuth.Clone)
-  * [func (n *NoAuth) Type() string](#NoAuth.Type)
+  * [func (p *PassportAuth) Close() error](#PassportAuth.Close)
-  * [func (n *NoAuth) User() string](#NoAuth.User)
+  * [func (p *PassportAuth) String() string](#PassportAuth.String)
+  * [func (p *PassportAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)](#PassportAuth.Verify)
+* [type StatusError](#StatusError)
+  * [func (se StatusError) Error() string](#StatusError.Error)
 
 ##### <a name="pkg-examples">Examples</a>
 * [PathEscape](#example_PathEscape)
 
 ##### <a name="pkg-files">Package files</a>
-[basicAuth.go](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go) [client.go](https://github.com/studio-b12/gowebdav/blob/master/client.go) [digestAuth.go](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go) [doc.go](https://github.com/studio-b12/gowebdav/blob/master/doc.go) [file.go](https://github.com/studio-b12/gowebdav/blob/master/file.go) [netrc.go](https://github.com/studio-b12/gowebdav/blob/master/netrc.go) [requests.go](https://github.com/studio-b12/gowebdav/blob/master/requests.go) [utils.go](https://github.com/studio-b12/gowebdav/blob/master/utils.go) 
+[auth.go](https://github.com/studio-b12/gowebdav/blob/master/auth.go) [basicAuth.go](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go) [client.go](https://github.com/studio-b12/gowebdav/blob/master/client.go) [digestAuth.go](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go) [doc.go](https://github.com/studio-b12/gowebdav/blob/master/doc.go) [errors.go](https://github.com/studio-b12/gowebdav/blob/master/errors.go) [file.go](https://github.com/studio-b12/gowebdav/blob/master/file.go) [netrc.go](https://github.com/studio-b12/gowebdav/blob/master/netrc.go) [passportAuth.go](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go) [requests.go](https://github.com/studio-b12/gowebdav/blob/master/requests.go) [utils.go](https://github.com/studio-b12/gowebdav/blob/master/utils.go) 
 
-### <a name="FixSlash">func</a> [FixSlash](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=707:737#L45)
+### <a name="pkg-constants">Constants</a>
+``` go
+const XInhibitRedirect = "X-Gowebdav-Inhibit-Redirect"
+```
+
+### <a name="pkg-variables">Variables</a>
+``` go
+var ErrAuthChanged = errors.New("authentication failed, change algorithm")
+```
+ErrAuthChanged must be returned from the Verify method as an error
+to trigger a re-authentication / negotiation with a new authenticator.
+
+``` go
+var ErrTooManyRedirects = errors.New("stopped after 10 redirects")
+```
+ErrTooManyRedirects will be used as return error if a request exceeds 10 redirects.
+
+### <a name="FixSlash">func</a> [FixSlash](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=354:384#L23)
 ``` go
 func FixSlash(s string) string
 ```
 FixSlash appends a trailing / to our string
 
-### <a name="FixSlashes">func</a> [FixSlashes](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=859:891#L53)
+### <a name="FixSlashes">func</a> [FixSlashes](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=506:538#L31)
 ``` go
 func FixSlashes(s string) string
 ```
 FixSlashes appends and prepends a / if they are missing
 
-### <a name="Join">func</a> [Join](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=976:1020#L61)
+### <a name="IsErrCode">func</a> [IsErrCode](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=740:780#L29)
+``` go
+func IsErrCode(err error, code int) bool
+```
+IsErrCode returns true if the given error
+is an os.PathError wrapping a StatusError
+with the given status code.
+
+### <a name="IsErrNotFound">func</a> [IsErrNotFound](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=972:1006#L39)
+``` go
+func IsErrNotFound(err error) bool
+```
+IsErrNotFound is shorthand for IsErrCode
+for status 404.
+
+### <a name="Join">func</a> [Join](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=639:683#L40)
 ``` go
 func Join(path0 string, path1 string) string
 ```
 Join joins two paths
 
-### <a name="PathEscape">func</a> [PathEscape](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=506:541#L36)
+### <a name="NewPathError">func</a> [NewPathError](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=1040:1103#L43)
+``` go
+func NewPathError(op string, path string, statusCode int) error
+```
+
+### <a name="NewPathErrorErr">func</a> [NewPathErrorErr](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=1194:1255#L51)
+``` go
+func NewPathErrorErr(op string, path string, err error) error
+```
+
+### <a name="PathEscape">func</a> [PathEscape](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=153:188#L14)
 ``` go
 func PathEscape(path string) string
 ```
-PathEscape escapes all segemnts of a given path
+PathEscape escapes all segments of a given path
 
 ### <a name="ReadConfig">func</a> [ReadConfig](https://github.com/studio-b12/gowebdav/blob/master/netrc.go?s=428:479#L27)
 ``` go
@@ -249,168 +328,302 @@ func ReadConfig(uri, netrc string) (string, string)
 ReadConfig reads login and password configuration from ~/.netrc
 machine foo.com login username password 123456
 
-### <a name="String">func</a> [String](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=1150:1181#L66)
+### <a name="String">func</a> [String](https://github.com/studio-b12/gowebdav/blob/master/utils.go?s=813:844#L45)
 ``` go
 func String(r io.Reader) string
 ```
 String pulls a string out of our io.Reader
 
-### <a name="Authenticator">type</a> [Authenticator](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=381:500#L28)
+### <a name="AuthFactory">type</a> [AuthFactory](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=150:251#L13)
+``` go
+type AuthFactory func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error)
+```
+AuthFactory prototype function to create a new Authenticator
+
+### <a name="Authenticator">type</a> [Authenticator](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=2155:2695#L56)
 ``` go
 type Authenticator interface {
-    Type() string
+    // Authorizes a request. Usually by adding some authorization headers.
-    User() string
+    Authorize(c *http.Client, rq *http.Request, path string) error
-    Pass() string
+    // Verifies the response if the authorization was successful.
-    Authorize(*http.Request, string, string)
+    // May trigger some round trips to pass the authentication.
+    // May also trigger a new Authenticator negotiation by returning `ErrAuthChenged`
+    Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+    // Creates a copy of the underlying Authenticator.
+    Clone() Authenticator
+    io.Closer
 }
 ```
-Authenticator stub
+A Authenticator implements a specific way to authorize requests.
+Each request is bound to a separate Authenticator instance.
 
-### <a name="BasicAuth">type</a> [BasicAuth](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=106:157#L9)
+The authentication flow itself is broken down into `Authorize`
+and `Verify` steps. The former method runs before, and the latter
+runs after the `Request` is submitted.
+This makes it easy to encapsulate and control complex
+authentication challenges.
+
+Some authentication flows causing authentication round trips,
+which can be archived by returning the `redo` of the Verify
+method. `True` restarts the authentication process for the
+current action: A new `Request` is spawned, which must be
+authorized, sent, and re-verified again, until the action
+is successfully submitted.
+The preferred way is to handle the authentication ping-pong
+within `Verify`, and then `redo` with fresh credentials.
+
+The result of the `Verify` method can also trigger an
+`Authenticator` change by returning the `ErrAuthChanged`
+as an error. Depending on the `Authorizer` this may trigger
+an `Authenticator` negotiation.
+
+Set the `XInhibitRedirect` header to '1' in the `Authorize`
+method to get control over request redirection.
+Attention! You must handle the incoming request yourself.
+
+To store a shared session state the `Clone` method **must**
+return a new instance, initialized with the shared state.
+
+#### <a name="NewDigestAuth">func</a> [NewDigestAuth](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=324:406#L21)
+``` go
+func NewDigestAuth(login, secret string, rs *http.Response) (Authenticator, error)
+```
+NewDigestAuth creates a new instance of our Digest Authenticator
+
+#### <a name="NewPassportAuth">func</a> [NewPassportAuth](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=386:495#L21)
+``` go
+func NewPassportAuth(c *http.Client, user, pw, partnerURL string, header *http.Header) (Authenticator, error)
+```
+constructor for PassportAuth creates a new PassportAuth object and
+automatically authenticates against the given partnerURL
+
+### <a name="Authorizer">type</a> [Authorizer](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=349:764#L17)
+``` go
+type Authorizer interface {
+    // Creates a new Authenticator Shim per request.
+    // It may track request related states and perform payload buffering
+    // for authentication round trips.
+    // The underlying Authenticator will perform the real authentication.
+    NewAuthenticator(body io.Reader) (Authenticator, io.Reader)
+    // Registers a new Authenticator factory to a key.
+    AddAuthenticator(key string, fn AuthFactory)
+}
+```
+Authorizer our Authenticator factory which creates an
+`Authenticator` per action/request.
+
+#### <a name="NewAutoAuth">func</a> [NewAutoAuth](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=3789:3845#L109)
+``` go
+func NewAutoAuth(login string, secret string) Authorizer
+```
+NewAutoAuth creates an auto Authenticator factory.
+It negotiates the default authentication method
+based on the order of the registered Authenticators
+and the remotely offered authentication methods.
+First In, First Out.
+
+#### <a name="NewEmptyAuth">func</a> [NewEmptyAuth](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=4694:4724#L132)
+``` go
+func NewEmptyAuth() Authorizer
+```
+NewEmptyAuth creates an empty Authenticator factory
+The order of adding the Authenticator matters.
+First In, First Out.
+It offers the `NewAutoAuth` features.
+
+#### <a name="NewPreemptiveAuth">func</a> [NewPreemptiveAuth](https://github.com/studio-b12/gowebdav/blob/master/auth.go?s=5300:5353#L148)
+``` go
+func NewPreemptiveAuth(auth Authenticator) Authorizer
+```
+NewPreemptiveAuth creates a preemptive Authenticator
+The preemptive authorizer uses the provided Authenticator
+for every request regardless of any `Www-Authenticate` header.
+
+It may only have one authentication method,
+so calling `AddAuthenticator` **will panic**!
+
+Look out!! This offers the skinniest and slickest implementation
+without any synchronisation!!
+Still applicable with `BasicAuth` within go routines.
+
+### <a name="BasicAuth">type</a> [BasicAuth](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=94:145#L9)
 ``` go
 type BasicAuth struct {
     // contains filtered or unexported fields
 }
+
 ```
 BasicAuth structure holds our credentials
 
-#### <a name="BasicAuth.Authorize">func</a> (\*BasicAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=473:549#L30)
+#### <a name="BasicAuth.Authorize">func</a> (\*BasicAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=180:262#L15)
 ``` go
-func (b *BasicAuth) Authorize(req *http.Request, method string, path string)
+func (b *BasicAuth) Authorize(c *http.Client, rq *http.Request, path string) error
 ```
 Authorize the current request
 
-#### <a name="BasicAuth.Pass">func</a> (\*BasicAuth) [Pass](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=388:421#L25)
+#### <a name="BasicAuth.Clone">func</a> (\*BasicAuth) [Clone](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=666:707#L34)
 ``` go
-func (b *BasicAuth) Pass() string
+func (b *BasicAuth) Clone() Authenticator
 ```
-Pass holds the BasicAuth password
+Clone creates a Copy of itself
 
-#### <a name="BasicAuth.Type">func</a> (\*BasicAuth) [Type](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=201:234#L15)
+#### <a name="BasicAuth.Close">func</a> (\*BasicAuth) [Close](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=581:614#L29)
 ``` go
-func (b *BasicAuth) Type() string
+func (b *BasicAuth) Close() error
 ```
-Type identifies the BasicAuthenticator
+Close cleans up all resources
 
-#### <a name="BasicAuth.User">func</a> (\*BasicAuth) [User](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=297:330#L20)
+#### <a name="BasicAuth.String">func</a> (\*BasicAuth) [String](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=778:813#L40)
 ``` go
-func (b *BasicAuth) User() string
+func (b *BasicAuth) String() string
 ```
-User holds the BasicAuth username
+String toString
 
-### <a name="Client">type</a> [Client](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=165:357#L17)
+#### <a name="BasicAuth.Verify">func</a> (\*BasicAuth) [Verify](https://github.com/studio-b12/gowebdav/blob/master/basicAuth.go?s=352:449#L21)
+``` go
+func (b *BasicAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+```
+Verify verifies if the authentication
+
+### <a name="Client">type</a> [Client](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=220:388#L19)
 ``` go
 type Client struct {
     // contains filtered or unexported fields
 }
+
 ```
 Client defines our structure
 
-#### <a name="NewClient">func</a> [NewClient](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1012:1056#L61)
+#### <a name="NewAuthClient">func</a> [NewAuthClient](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=608:663#L33)
+``` go
+func NewAuthClient(uri string, auth Authorizer) *Client
+```
+NewAuthClient creates a new client instance with a custom Authorizer
+
+#### <a name="NewClient">func</a> [NewClient](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=436:480#L28)
 ``` go
 func NewClient(uri, user, pw string) *Client
 ```
 NewClient creates a new instance of client
 
-#### <a name="Client.Connect">func</a> (\*Client) [Connect](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1836:1868#L86)
+#### <a name="Client.Connect">func</a> (\*Client) [Connect](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1829:1861#L74)
 ``` go
 func (c *Client) Connect() error
 ```
 Connect connects to our dav server
 
-#### <a name="Client.Copy">func</a> (\*Client) [Copy](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6695:6763#L312)
+#### <a name="Client.Copy">func</a> (\*Client) [Copy](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6815:6883#L310)
 ``` go
 func (c *Client) Copy(oldpath, newpath string, overwrite bool) error
 ```
 Copy copies a file from A to B
 
-#### <a name="Client.Mkdir">func</a> (\*Client) [Mkdir](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5786:5842#L271)
+#### <a name="Client.Mkdir">func</a> (\*Client) [Mkdir](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5790:5852#L259)
 ``` go
-func (c *Client) Mkdir(path string, _ os.FileMode) error
+func (c *Client) Mkdir(path string, _ os.FileMode) (err error)
 ```
 Mkdir makes a directory
 
-#### <a name="Client.MkdirAll">func</a> (\*Client) [MkdirAll](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6021:6080#L282)
+#### <a name="Client.MkdirAll">func</a> (\*Client) [MkdirAll](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6065:6130#L273)
 ``` go
-func (c *Client) MkdirAll(path string, _ os.FileMode) error
+func (c *Client) MkdirAll(path string, _ os.FileMode) (err error)
 ```
 MkdirAll like mkdir -p, but for webdav
 
-#### <a name="Client.Read">func</a> (\*Client) [Read](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6869:6919#L317)
+#### <a name="Client.Read">func</a> (\*Client) [Read](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6989:7039#L315)
 ``` go
 func (c *Client) Read(path string) ([]byte, error)
 ```
 Read reads the contents of a remote file
 
-#### <a name="Client.ReadDir">func</a> (\*Client) [ReadDir](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=2862:2922#L129)
+#### <a name="Client.ReadDir">func</a> (\*Client) [ReadDir](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=2855:2915#L117)
 ``` go
 func (c *Client) ReadDir(path string) ([]os.FileInfo, error)
 ```
 ReadDir reads the contents of a remote directory
 
-#### <a name="Client.ReadStream">func</a> (\*Client) [ReadStream](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=7230:7293#L335)
+#### <a name="Client.ReadStream">func</a> (\*Client) [ReadStream](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=7350:7413#L333)
 ``` go
 func (c *Client) ReadStream(path string) (io.ReadCloser, error)
 ```
 ReadStream reads the stream for a given path
 
-#### <a name="Client.Remove">func</a> (\*Client) [Remove](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5292:5334#L248)
+#### <a name="Client.ReadStreamRange">func</a> (\*Client) [ReadStreamRange](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=8162:8252#L355)
+``` go
+func (c *Client) ReadStreamRange(path string, offset, length int64) (io.ReadCloser, error)
+```
+ReadStreamRange reads the stream representing a subset of bytes for a given path,
+utilizing HTTP Range Requests if the server supports it.
+The range is expressed as offset from the start of the file and length, for example
+offset=10, length=10 will return bytes 10 through 19.
+
+If the server does not support partial content requests and returns full content instead,
+this function will emulate the behavior by skipping `offset` bytes and limiting the result
+to `length`.
+
+#### <a name="Client.Remove">func</a> (\*Client) [Remove](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5296:5338#L236)
 ``` go
 func (c *Client) Remove(path string) error
 ```
 Remove removes a remote file
 
-#### <a name="Client.RemoveAll">func</a> (\*Client) [RemoveAll](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5400:5445#L253)
+#### <a name="Client.RemoveAll">func</a> (\*Client) [RemoveAll](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=5404:5449#L241)
 ``` go
 func (c *Client) RemoveAll(path string) error
 ```
 RemoveAll removes remote files
 
-#### <a name="Client.Rename">func</a> (\*Client) [Rename](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6529:6599#L307)
+#### <a name="Client.Rename">func</a> (\*Client) [Rename](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=6649:6719#L305)
 ``` go
 func (c *Client) Rename(oldpath, newpath string, overwrite bool) error
 ```
 Rename moves a file from A to B
 
-#### <a name="Client.SetHeader">func</a> (\*Client) [SetHeader](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1228:1273#L66)
+#### <a name="Client.SetHeader">func</a> (\*Client) [SetHeader](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1092:1137#L49)
 ``` go
 func (c *Client) SetHeader(key, value string)
 ```
 SetHeader lets us set arbitrary headers for a given client
 
-#### <a name="Client.SetInterceptor">func</a> (\*Client) [SetInterceptor](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1380:1462#L71)
+#### <a name="Client.SetInterceptor">func</a> (\*Client) [SetInterceptor](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1244:1326#L54)
 ``` go
 func (c *Client) SetInterceptor(interceptor func(method string, rq *http.Request))
 ```
 SetInterceptor lets us set an arbitrary interceptor for a given client
 
-#### <a name="Client.SetTimeout">func</a> (\*Client) [SetTimeout](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1564:1614#L76)
+#### <a name="Client.SetJar">func</a> (\*Client) [SetJar](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1727:1770#L69)
+``` go
+func (c *Client) SetJar(jar http.CookieJar)
+```
+SetJar exposes the ability to set a cookie jar to the client.
+
+#### <a name="Client.SetTimeout">func</a> (\*Client) [SetTimeout](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1428:1478#L59)
 ``` go
 func (c *Client) SetTimeout(timeout time.Duration)
 ```
 SetTimeout exposes the ability to set a time limit for requests
 
-#### <a name="Client.SetTransport">func</a> (\*Client) [SetTransport](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1707:1765#L81)
+#### <a name="Client.SetTransport">func</a> (\*Client) [SetTransport](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=1571:1629#L64)
 ``` go
 func (c *Client) SetTransport(transport http.RoundTripper)
 ```
 SetTransport exposes the ability to define custom transports
 
-#### <a name="Client.Stat">func</a> (\*Client) [Stat](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=4248:4303#L196)
+#### <a name="Client.Stat">func</a> (\*Client) [Stat](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=4241:4296#L184)
 ``` go
 func (c *Client) Stat(path string) (os.FileInfo, error)
 ```
 Stat returns the file stats for a specified path
 
-#### <a name="Client.Write">func</a> (\*Client) [Write](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=7584:7653#L350)
+#### <a name="Client.Write">func</a> (\*Client) [Write](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=9272:9347#L389)
 ``` go
-func (c *Client) Write(path string, data []byte, _ os.FileMode) error
+func (c *Client) Write(path string, data []byte, _ os.FileMode) (err error)
 ```
 Write writes data to a given path
 
-#### <a name="Client.WriteStream">func</a> (\*Client) [WriteStream](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=8009:8089#L373)
+#### <a name="Client.WriteStream">func</a> (\*Client) [WriteStream](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=9771:9857#L419)
 ``` go
-func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) error
+func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) (err error)
 ```
 WriteStream writes a stream
 
@@ -419,38 +632,46 @@ WriteStream writes a stream
 type DigestAuth struct {
     // contains filtered or unexported fields
 }
+
 ```
 DigestAuth structure holds our credentials
 
-#### <a name="DigestAuth.Authorize">func</a> (\*DigestAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=577:654#L36)
+#### <a name="DigestAuth.Authorize">func</a> (\*DigestAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=525:608#L26)
 ``` go
-func (d *DigestAuth) Authorize(req *http.Request, method string, path string)
+func (d *DigestAuth) Authorize(c *http.Client, rq *http.Request, path string) error
 ```
 Authorize the current request
 
-#### <a name="DigestAuth.Pass">func</a> (\*DigestAuth) [Pass](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=491:525#L31)
+#### <a name="DigestAuth.Clone">func</a> (\*DigestAuth) [Clone](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=1228:1270#L49)
 ``` go
-func (d *DigestAuth) Pass() string
+func (d *DigestAuth) Clone() Authenticator
 ```
-Pass holds the DigestAuth password
+Clone creates a copy of itself
 
-#### <a name="DigestAuth.Type">func</a> (\*DigestAuth) [Type](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=299:333#L21)
+#### <a name="DigestAuth.Close">func</a> (\*DigestAuth) [Close](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=1142:1176#L44)
 ``` go
-func (d *DigestAuth) Type() string
+func (d *DigestAuth) Close() error
 ```
-Type identifies the DigestAuthenticator
+Close cleans up all resources
 
-#### <a name="DigestAuth.User">func</a> (\*DigestAuth) [User](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=398:432#L26)
+#### <a name="DigestAuth.String">func</a> (\*DigestAuth) [String](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=1466:1502#L58)
 ``` go
-func (d *DigestAuth) User() string
+func (d *DigestAuth) String() string
 ```
-User holds the DigestAuth username
+String toString
+
+#### <a name="DigestAuth.Verify">func</a> (\*DigestAuth) [Verify](https://github.com/studio-b12/gowebdav/blob/master/digestAuth.go?s=912:1010#L36)
+``` go
+func (d *DigestAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+```
+Verify checks for authentication issues and may trigger a re-authentication
 
 ### <a name="File">type</a> [File](https://github.com/studio-b12/gowebdav/blob/master/file.go?s=93:253#L10)
 ``` go
 type File struct {
     // contains filtered or unexported fields
 }
+
 ```
 File is our structure for a given file
 
@@ -514,37 +735,59 @@ func (f File) Sys() interface{}
 ```
 Sys ????
 
-### <a name="NoAuth">type</a> [NoAuth](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=544:592#L36)
+### <a name="PassportAuth">type</a> [PassportAuth](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=125:254#L12)
 ``` go
-type NoAuth struct {
+type PassportAuth struct {
     // contains filtered or unexported fields
 }
-```
-NoAuth structure holds our credentials
 
-#### <a name="NoAuth.Authorize">func</a> (\*NoAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=887:960#L57)
+```
+PassportAuth structure holds our credentials
+
+#### <a name="PassportAuth.Authorize">func</a> (\*PassportAuth) [Authorize](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=690:775#L32)
 ``` go
-func (n *NoAuth) Authorize(req *http.Request, method string, path string)
+func (p *PassportAuth) Authorize(c *http.Client, rq *http.Request, path string) error
 ```
 Authorize the current request
 
-#### <a name="NoAuth.Pass">func</a> (\*NoAuth) [Pass](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=805:835#L52)
+#### <a name="PassportAuth.Clone">func</a> (\*PassportAuth) [Clone](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=1701:1745#L69)
 ``` go
-func (n *NoAuth) Pass() string
+func (p *PassportAuth) Clone() Authenticator
 ```
-Pass returns the current password
+Clone creates a Copy of itself
 
-#### <a name="NoAuth.Type">func</a> (\*NoAuth) [Type](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=631:661#L42)
+#### <a name="PassportAuth.Close">func</a> (\*PassportAuth) [Close](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=1613:1649#L64)
 ``` go
-func (n *NoAuth) Type() string
+func (p *PassportAuth) Close() error
 ```
-Type identifies the authenticator
+Close cleans up all resources
 
-#### <a name="NoAuth.User">func</a> (\*NoAuth) [User](https://github.com/studio-b12/gowebdav/blob/master/client.go?s=717:747#L47)
+#### <a name="PassportAuth.String">func</a> (\*PassportAuth) [String](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=2048:2086#L83)
 ``` go
-func (n *NoAuth) User() string
+func (p *PassportAuth) String() string
+```
+String toString
+
+#### <a name="PassportAuth.Verify">func</a> (\*PassportAuth) [Verify](https://github.com/studio-b12/gowebdav/blob/master/passportAuth.go?s=1075:1175#L46)
+``` go
+func (p *PassportAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+```
+Verify verifies if the authentication is good
+
+### <a name="StatusError">type</a> [StatusError](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=499:538#L18)
+``` go
+type StatusError struct {
+    Status int
+}
+
+```
+StatusError implements error and wraps
+an erroneous status code.
+
+#### <a name="StatusError.Error">func</a> (StatusError) [Error](https://github.com/studio-b12/gowebdav/blob/master/errors.go?s=540:576#L22)
+``` go
+func (se StatusError) Error() string
 ```
-User returns the current user
 
 - - -
 Generated by [godoc2md](http://godoc.org/github.com/davecheney/godoc2md)

auth.go

@@ -0,0 +1,409 @@
+package gowebdav
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"net/http"
+	"strings"
+	"sync"
+)
+
+// AuthFactory prototype function to create a new Authenticator
+type AuthFactory func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error)
+
+// Authorizer our Authenticator factory which creates an
+// `Authenticator` per action/request.
+type Authorizer interface {
+	// Creates a new Authenticator Shim per request.
+	// It may track request related states and perform payload buffering
+	// for authentication round trips.
+	// The underlying Authenticator will perform the real authentication.
+	NewAuthenticator(body io.Reader) (Authenticator, io.Reader)
+	// Registers a new Authenticator factory to a key.
+	AddAuthenticator(key string, fn AuthFactory)
+}
+
+// A Authenticator implements a specific way to authorize requests.
+// Each request is bound to a separate Authenticator instance.
+//
+// The authentication flow itself is broken down into `Authorize`
+// and `Verify` steps. The former method runs before, and the latter
+// runs after the `Request` is submitted.
+// This makes it easy to encapsulate and control complex
+// authentication challenges.
+//
+// Some authentication flows causing authentication round trips,
+// which can be archived by returning the `redo` of the Verify
+// method. `True` restarts the authentication process for the
+// current action: A new `Request` is spawned, which must be
+// authorized, sent, and re-verified again, until the action
+// is successfully submitted.
+// The preferred way is to handle the authentication ping-pong
+// within `Verify`, and then `redo` with fresh credentials.
+//
+// The result of the `Verify` method can also trigger an
+// `Authenticator` change by returning the `ErrAuthChanged`
+// as an error. Depending on the `Authorizer` this may trigger
+// an `Authenticator` negotiation.
+//
+// Set the `XInhibitRedirect` header to '1' in the `Authorize`
+// method to get control over request redirection.
+// Attention! You must handle the incoming request yourself.
+//
+// To store a shared session state the `Clone` method **must**
+// return a new instance, initialized with the shared state.
+type Authenticator interface {
+	// Authorizes a request. Usually by adding some authorization headers.
+	Authorize(c *http.Client, rq *http.Request, path string) error
+	// Verifies the response if the authorization was successful.
+	// May trigger some round trips to pass the authentication.
+	// May also trigger a new Authenticator negotiation by returning `ErrAuthChenged`
+	Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error)
+	// Creates a copy of the underlying Authenticator.
+	Clone() Authenticator
+	io.Closer
+}
+
+type authfactory struct {
+	key    string
+	create AuthFactory
+}
+
+// authorizer structure holds our Authenticator create functions
+type authorizer struct {
+	factories  []authfactory
+	defAuthMux sync.Mutex
+	defAuth    Authenticator
+}
+
+// preemptiveAuthorizer structure holds the preemptive Authenticator
+type preemptiveAuthorizer struct {
+	auth Authenticator
+}
+
+// authShim structure that wraps the real Authenticator
+type authShim struct {
+	factory AuthFactory
+	body    io.Reader
+	auth    Authenticator
+}
+
+// negoAuth structure holds the authenticators that are going to be negotiated
+type negoAuth struct {
+	auths                   []Authenticator
+	setDefaultAuthenticator func(auth Authenticator)
+}
+
+// nullAuth initializes the whole authentication flow
+type nullAuth struct{}
+
+// noAuth structure to perform no authentication at all
+type noAuth struct{}
+
+// NewAutoAuth creates an auto Authenticator factory.
+// It negotiates the default authentication method
+// based on the order of the registered Authenticators
+// and the remotely offered authentication methods.
+// First In, First Out.
+func NewAutoAuth(login string, secret string) Authorizer {
+	fmap := make([]authfactory, 0)
+	az := &authorizer{factories: fmap, defAuthMux: sync.Mutex{}, defAuth: &nullAuth{}}
+
+	az.AddAuthenticator("basic", func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error) {
+		return &BasicAuth{user: login, pw: secret}, nil
+	})
+
+	az.AddAuthenticator("digest", func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error) {
+		return NewDigestAuth(login, secret, rs)
+	})
+
+	az.AddAuthenticator("passport1.4", func(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error) {
+		return NewPassportAuth(c, login, secret, rs.Request.URL.String(), &rs.Header)
+	})
+
+	return az
+}
+
+// NewEmptyAuth creates an empty Authenticator factory
+// The order of adding the Authenticator matters.
+// First In, First Out.
+// It offers the `NewAutoAuth` features.
+func NewEmptyAuth() Authorizer {
+	fmap := make([]authfactory, 0)
+	az := &authorizer{factories: fmap, defAuthMux: sync.Mutex{}, defAuth: &nullAuth{}}
+	return az
+}
+
+// NewPreemptiveAuth creates a preemptive Authenticator
+// The preemptive authorizer uses the provided Authenticator
+// for every request regardless of any `Www-Authenticate` header.
+//
+// It may only have one authentication method,
+// so calling `AddAuthenticator` **will panic**!
+//
+// Look out!! This offers the skinniest and slickest implementation
+// without any synchronisation!!
+// Still applicable with `BasicAuth` within go routines.
+func NewPreemptiveAuth(auth Authenticator) Authorizer {
+	return &preemptiveAuthorizer{auth: auth}
+}
+
+// NewAuthenticator creates an Authenticator (Shim) per request
+func (a *authorizer) NewAuthenticator(body io.Reader) (Authenticator, io.Reader) {
+	var retryBuf io.Reader = body
+	if body != nil {
+		// If the authorization fails, we will need to restart reading
+		// from the passed body stream.
+		// When body is seekable, use seek to reset the streams
+		// cursor to the start.
+		// Otherwise, copy the stream into a buffer while uploading
+		// and use the buffers content on retry.
+		if _, ok := retryBuf.(io.Seeker); ok {
+			body = io.NopCloser(body)
+		} else {
+			buff := &bytes.Buffer{}
+			retryBuf = buff
+			body = io.TeeReader(body, buff)
+		}
+	}
+	a.defAuthMux.Lock()
+	defAuth := a.defAuth.Clone()
+	a.defAuthMux.Unlock()
+
+	return &authShim{factory: a.factory, body: retryBuf, auth: defAuth}, body
+}
+
+// AddAuthenticator appends the AuthFactory to our factories.
+// It converts the key to lower case and preserves the order.
+func (a *authorizer) AddAuthenticator(key string, fn AuthFactory) {
+	key = strings.ToLower(key)
+	for _, f := range a.factories {
+		if f.key == key {
+			panic("Authenticator exists: " + key)
+		}
+	}
+	a.factories = append(a.factories, authfactory{key, fn})
+}
+
+// factory picks all valid Authenticators based on Www-Authenticate headers
+func (a *authorizer) factory(c *http.Client, rs *http.Response, path string) (auth Authenticator, err error) {
+	headers := rs.Header.Values("Www-Authenticate")
+	if len(headers) > 0 {
+		auths := make([]Authenticator, 0)
+		for _, f := range a.factories {
+			for _, header := range headers {
+				headerLower := strings.ToLower(header)
+				if strings.Contains(headerLower, f.key) {
+					rs.Header.Set("Www-Authenticate", header)
+					if auth, err = f.create(c, rs, path); err == nil {
+						auths = append(auths, auth)
+						break
+					}
+				}
+			}
+		}
+
+		switch len(auths) {
+		case 0:
+			return nil, NewPathError("NoAuthenticator", path, rs.StatusCode)
+		case 1:
+			auth = auths[0]
+		default:
+			auth = &negoAuth{auths: auths, setDefaultAuthenticator: a.setDefaultAuthenticator}
+		}
+	} else {
+		auth = &noAuth{}
+	}
+
+	a.setDefaultAuthenticator(auth)
+
+	return auth, nil
+}
+
+// setDefaultAuthenticator sets the default Authenticator
+func (a *authorizer) setDefaultAuthenticator(auth Authenticator) {
+	a.defAuthMux.Lock()
+	a.defAuth.Close()
+	a.defAuth = auth
+	a.defAuthMux.Unlock()
+}
+
+// Authorize the current request
+func (s *authShim) Authorize(c *http.Client, rq *http.Request, path string) error {
+	if err := s.auth.Authorize(c, rq, path); err != nil {
+		return err
+	}
+	body := s.body
+	rq.GetBody = func() (io.ReadCloser, error) {
+		if body != nil {
+			if sk, ok := body.(io.Seeker); ok {
+				if _, err := sk.Seek(0, io.SeekStart); err != nil {
+					return nil, err
+				}
+			}
+			return io.NopCloser(body), nil
+		}
+		return nil, nil
+	}
+	return nil
+}
+
+// Verify checks for authentication issues and may trigger a re-authentication.
+// Catches AlgoChangedErr to update the current Authenticator
+func (s *authShim) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	redo, err = s.auth.Verify(c, rs, path)
+	if err != nil && errors.Is(err, ErrAuthChanged) {
+		if auth, aerr := s.factory(c, rs, path); aerr == nil {
+			s.auth.Close()
+			s.auth = auth
+			return true, nil
+		} else {
+			return false, aerr
+		}
+	}
+	return
+}
+
+// Close closes all resources
+func (s *authShim) Close() error {
+	s.auth.Close()
+	s.auth, s.factory = nil, nil
+	if s.body != nil {
+		if closer, ok := s.body.(io.Closer); ok {
+			return closer.Close()
+		}
+	}
+	return nil
+}
+
+// It's not intend to Clone the shim
+// therefore it returns a noAuth instance
+func (s *authShim) Clone() Authenticator {
+	return &noAuth{}
+}
+
+// String toString
+func (s *authShim) String() string {
+	return "AuthShim"
+}
+
+// Authorize authorizes the current request with the top most Authorizer
+func (n *negoAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	if len(n.auths) == 0 {
+		return NewPathError("NoAuthenticator", path, 400)
+	}
+	return n.auths[0].Authorize(c, rq, path)
+}
+
+// Verify verifies the authentication and selects the next one based on the result
+func (n *negoAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	if len(n.auths) == 0 {
+		return false, NewPathError("NoAuthenticator", path, 400)
+	}
+	redo, err = n.auths[0].Verify(c, rs, path)
+	if err != nil {
+		if len(n.auths) > 1 {
+			n.auths[0].Close()
+			n.auths = n.auths[1:]
+			return true, nil
+		}
+	} else if redo {
+		return
+	} else {
+		auth := n.auths[0]
+		n.auths = n.auths[1:]
+		n.setDefaultAuthenticator(auth)
+		return
+	}
+
+	return false, NewPathError("NoAuthenticator", path, rs.StatusCode)
+}
+
+// Close will close the underlying authenticators.
+func (n *negoAuth) Close() error {
+	for _, a := range n.auths {
+		a.Close()
+	}
+	n.setDefaultAuthenticator = nil
+	return nil
+}
+
+// Clone clones the underlying authenticators.
+func (n *negoAuth) Clone() Authenticator {
+	auths := make([]Authenticator, len(n.auths))
+	for i, e := range n.auths {
+		auths[i] = e.Clone()
+	}
+	return &negoAuth{auths: auths, setDefaultAuthenticator: n.setDefaultAuthenticator}
+}
+
+func (n *negoAuth) String() string {
+	return "NegoAuth"
+}
+
+// Authorize the current request
+func (n *noAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	return nil
+}
+
+// Verify checks for authentication issues and may trigger a re-authentication
+func (n *noAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	if "" != rs.Header.Get("Www-Authenticate") {
+		err = ErrAuthChanged
+	}
+	return
+}
+
+// Close closes all resources
+func (n *noAuth) Close() error {
+	return nil
+}
+
+// Clone creates a copy of itself
+func (n *noAuth) Clone() Authenticator {
+	// no copy due to read only access
+	return n
+}
+
+// String toString
+func (n *noAuth) String() string {
+	return "NoAuth"
+}
+
+// Authorize the current request
+func (n *nullAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	rq.Header.Set(XInhibitRedirect, "1")
+	return nil
+}
+
+// Verify checks for authentication issues and may trigger a re-authentication
+func (n *nullAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	return true, ErrAuthChanged
+}
+
+// Close closes all resources
+func (n *nullAuth) Close() error {
+	return nil
+}
+
+// Clone creates a copy of itself
+func (n *nullAuth) Clone() Authenticator {
+	// no copy due to read only access
+	return n
+}
+
+// String toString
+func (n *nullAuth) String() string {
+	return "NullAuth"
+}
+
+// NewAuthenticator creates an Authenticator (Shim) per request
+func (b *preemptiveAuthorizer) NewAuthenticator(body io.Reader) (Authenticator, io.Reader) {
+	return b.auth.Clone(), body
+}
+
+// AddAuthenticator Will PANIC because it may only have a single authentication method
+func (b *preemptiveAuthorizer) AddAuthenticator(key string, fn AuthFactory) {
+	panic("You're funny! A preemptive authorizer may only have a single authentication method")
+}

auth_test.go

@@ -0,0 +1,62 @@
+package gowebdav
+
+import (
+	"bytes"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestEmptyAuth(t *testing.T) {
+	auth := NewEmptyAuth()
+	srv, _, _ := newAuthSrv(t, basicAuth)
+	defer srv.Close()
+	cli := NewAuthClient(srv.URL, auth)
+	if err := cli.Connect(); err == nil {
+		t.Fatalf("got nil want error")
+	}
+}
+
+func TestRedirectAuthWIP(t *testing.T) {
+	hasPassedAuthServer := false
+	authHandler := func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			if user, passwd, ok := r.BasicAuth(); ok {
+				if user == "user" && passwd == "password" {
+					hasPassedAuthServer = true
+					w.WriteHeader(200)
+					return
+				}
+			}
+			w.Header().Set("Www-Authenticate", `Basic realm="x"`)
+			w.WriteHeader(401)
+		}
+	}
+
+	psrv, _, _ := newAuthSrv(t, authHandler)
+	defer psrv.Close()
+
+	dataHandler := func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			hasAuth := strings.Contains(r.Header.Get("Authorization"), "Basic dXNlcjpwYXNzd29yZA==")
+
+			if hasPassedAuthServer && hasAuth {
+				h.ServeHTTP(w, r)
+				return
+			}
+			w.Header().Set("Www-Authenticate", `Basic realm="x"`)
+			http.Redirect(w, r, psrv.URL+"/", 302)
+		}
+	}
+
+	srv, _, _ := newAuthSrv(t, dataHandler)
+	defer srv.Close()
+	cli := NewClient(srv.URL, "user", "password")
+	data, err := cli.Read("/hello.txt")
+	if err != nil {
+		t.Logf("WIP got error=%v; want nil", err)
+	}
+	if bytes.Compare(data, []byte("hello gowebdav\n")) != 0 {
+		t.Logf("WIP got data=%v; want=hello gowebdav", data)
+	}
+}

basicAuth.go

@@ -1,7 +1,7 @@
 package gowebdav
 
 import (
-	"encoding/base64"
+	"fmt"
 	"net/http"
 )
 
@@ -11,24 +11,37 @@ type BasicAuth struct {
 	pw   string
 }
 
-// Type identifies the BasicAuthenticator
+// NewDigestAuth creates a new instance of our Digest Authenticator
-func (b *BasicAuth) Type() string {
+func NewBasicAuth(login, secret string) (Authenticator, error) {
-	return "BasicAuth"
+	return &BasicAuth{user: login, pw: secret}, nil
-}
-
-// User holds the BasicAuth username
-func (b *BasicAuth) User() string {
-	return b.user
-}
-
-// Pass holds the BasicAuth password
-func (b *BasicAuth) Pass() string {
-	return b.pw
 }
 
 // Authorize the current request
-func (b *BasicAuth) Authorize(req *http.Request, method string, path string) {
+func (b *BasicAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
-	a := b.user + ":" + b.pw
+	rq.SetBasicAuth(b.user, b.pw)
-	auth := "Basic " + base64.StdEncoding.EncodeToString([]byte(a))
+	return nil
-	req.Header.Set("Authorization", auth)
+}
+
+// Verify verifies if the authentication
+func (b *BasicAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	if rs.StatusCode == 401 {
+		err = NewPathError("Authorize", path, rs.StatusCode)
+	}
+	return
+}
+
+// Close cleans up all resources
+func (b *BasicAuth) Close() error {
+	return nil
+}
+
+// Clone creates a Copy of itself
+func (b *BasicAuth) Clone() Authenticator {
+	// no copy due to read only access
+	return b
+}
+
+// String toString
+func (b *BasicAuth) String() string {
+	return fmt.Sprintf("BasicAuth login: %s", b.user)
 }

basicAuth_test.go

@@ -0,0 +1,51 @@
+package gowebdav
+
+import (
+	"net/http"
+	"testing"
+)
+
+func TestNewBasicAuth(t *testing.T) {
+	a := &BasicAuth{user: "user", pw: "password"}
+
+	ex := "BasicAuth login: user"
+	if a.String() != ex {
+		t.Error("expected: " + ex + " got: " + a.String())
+	}
+
+	if a.Clone() != a {
+		t.Error("expected the same instance")
+	}
+
+	if a.Close() != nil {
+		t.Error("expected close without errors")
+	}
+}
+
+func TestBasicAuthAuthorize(t *testing.T) {
+	a := &BasicAuth{user: "user", pw: "password"}
+	rq, _ := http.NewRequest("GET", "http://localhost/", nil)
+	a.Authorize(nil, rq, "/")
+	if rq.Header.Get("Authorization") != "Basic dXNlcjpwYXNzd29yZA==" {
+		t.Error("got wrong Authorization header: " + rq.Header.Get("Authorization"))
+	}
+}
+
+func TestPreemtiveBasicAuth(t *testing.T) {
+	a := &BasicAuth{user: "user", pw: "password"}
+	auth := NewPreemptiveAuth(a)
+	n, b := auth.NewAuthenticator(nil)
+	if b != nil {
+		t.Error("expected body to be nil")
+	}
+	if n != a {
+		t.Error("expected the same instance")
+	}
+
+	srv, _, _ := newAuthSrv(t, basicAuth)
+	defer srv.Close()
+	cli := NewAuthClient(srv.URL, auth)
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got error: %v, want nil", err)
+	}
+}

client.go

@@ -10,57 +10,39 @@ import (
 	"os"
 	pathpkg "path"
 	"strings"
-	"sync"
 	"time"
 )
 
+const XInhibitRedirect = "X-Gowebdav-Inhibit-Redirect"
+
 // Client defines our structure
 type Client struct {
 	root        string
 	headers     http.Header
 	interceptor func(method string, rq *http.Request)
 	c           *http.Client
-
+	auth        Authorizer
-	authMutex sync.Mutex
-	auth      Authenticator
-}
-
-// Authenticator stub
-type Authenticator interface {
-	Type() string
-	User() string
-	Pass() string
-	Authorize(*http.Request, string, string)
-}
-
-// NoAuth structure holds our credentials
-type NoAuth struct {
-	user string
-	pw   string
-}
-
-// Type identifies the authenticator
-func (n *NoAuth) Type() string {
-	return "NoAuth"
-}
-
-// User returns the current user
-func (n *NoAuth) User() string {
-	return n.user
-}
-
-// Pass returns the current password
-func (n *NoAuth) Pass() string {
-	return n.pw
-}
-
-// Authorize the current request
-func (n *NoAuth) Authorize(req *http.Request, method string, path string) {
 }
 
 // NewClient creates a new instance of client
 func NewClient(uri, user, pw string) *Client {
-	return &Client{FixSlash(uri), make(http.Header), nil, &http.Client{}, sync.Mutex{}, &NoAuth{user, pw}}
+	return NewAuthClient(uri, NewAutoAuth(user, pw))
+}
+
+// NewAuthClient creates a new client instance with a custom Authorizer
+func NewAuthClient(uri string, auth Authorizer) *Client {
+	c := &http.Client{
+		CheckRedirect: func(rq *http.Request, via []*http.Request) error {
+			if len(via) >= 10 {
+				return ErrTooManyRedirects
+			}
+			if via[0].Header.Get(XInhibitRedirect) != "" {
+				return http.ErrUseLastResponse
+			}
+			return nil
+		},
+	}
+	return &Client{root: FixSlash(uri), headers: make(http.Header), interceptor: nil, c: c, auth: auth}
 }
 
 // SetHeader lets us set arbitrary headers for a given client
@@ -83,6 +65,11 @@ func (c *Client) SetTransport(transport http.RoundTripper) {
 	c.c.Transport = transport
 }
 
+// SetJar exposes the ability to set a cookie jar to the client.
+func (c *Client) SetJar(jar http.CookieJar) {
+	c.c.Jar = jar
+}
+
 // Connect connects to our dav server
 func (c *Client) Connect() error {
 	rs, err := c.options("/")
@@ -96,7 +83,7 @@ func (c *Client) Connect() error {
 	}
 
 	if rs.StatusCode != 200 {
-		return newPathError("Connect", c.root, rs.StatusCode)
+		return NewPathError("Connect", c.root, rs.StatusCode)
 	}
 
 	return nil
@@ -140,7 +127,7 @@ func (c *Client) ReadDir(path string) ([]os.FileInfo, error) {
 				r.Props = nil
 				return nil
 			}
-			return newPathError("ReadDir", path, 405)
+			return NewPathError("ReadDir", path, 405)
 		}
 
 		if p := getProps(r, "200"); p != nil {
@@ -187,7 +174,7 @@ func (c *Client) ReadDir(path string) ([]os.FileInfo, error) {
 
 	if err != nil {
 		if _, ok := err.(*os.PathError); !ok {
-			err = newPathErrorErr("ReadDir", path, err)
+			err = NewPathErrorErr("ReadDir", path, err)
 		}
 	}
 	return files, err
@@ -210,7 +197,7 @@ func (c *Client) Stat(path string) (os.FileInfo, error) {
 					f.path += "/"
 				}
 				f.size = 0
-				f.modified = time.Unix(0, 0)
+				f.modified = parseModified(&p.Modified)
 				f.isdir = true
 			} else {
 				f.size = parseInt64(&p.Size)
@@ -239,7 +226,7 @@ func (c *Client) Stat(path string) (os.FileInfo, error) {
 
 	if err != nil {
 		if _, ok := err.(*os.PathError); !ok {
-			err = newPathErrorErr("ReadDir", path, err)
+			err = NewPathErrorErr("ReadDir", path, err)
 		}
 	}
 	return f, err
@@ -254,7 +241,7 @@ func (c *Client) Remove(path string) error {
 func (c *Client) RemoveAll(path string) error {
 	rs, err := c.req("DELETE", path, nil, nil)
 	if err != nil {
-		return newPathError("Remove", path, 400)
+		return NewPathError("Remove", path, 400)
 	}
 	err = rs.Body.Close()
 	if err != nil {
@@ -265,27 +252,34 @@ func (c *Client) RemoveAll(path string) error {
 		return nil
 	}
 
-	return newPathError("Remove", path, rs.StatusCode)
+	return NewPathError("Remove", path, rs.StatusCode)
 }
 
 // Mkdir makes a directory
-func (c *Client) Mkdir(path string, _ os.FileMode) error {
+func (c *Client) Mkdir(path string, _ os.FileMode) (err error) {
 	path = FixSlashes(path)
-	status := c.mkcol(path)
+	status, err := c.mkcol(path)
+	if err != nil {
+		return
+	}
 	if status == 201 {
 		return nil
 	}
 
-	return newPathError("Mkdir", path, status)
+	return NewPathError("Mkdir", path, status)
 }
 
 // MkdirAll like mkdir -p, but for webdav
-func (c *Client) MkdirAll(path string, _ os.FileMode) error {
+func (c *Client) MkdirAll(path string, _ os.FileMode) (err error) {
 	path = FixSlashes(path)
-	status := c.mkcol(path)
+	status, err := c.mkcol(path)
+	if err != nil {
+		return
+	}
 	if status == 201 {
 		return nil
-	} else if status == 409 {
+	}
+	if status == 409 {
 		paths := strings.Split(path, "/")
 		sub := "/"
 		for _, e := range paths {
@@ -293,15 +287,18 @@ func (c *Client) MkdirAll(path string, _ os.FileMode) error {
 				continue
 			}
 			sub += e + "/"
-			status = c.mkcol(sub)
+			status, err = c.mkcol(sub)
+			if err != nil {
+				return
+			}
 			if status != 201 {
-				return newPathError("MkdirAll", sub, status)
+				return NewPathError("MkdirAll", sub, status)
 			}
 		}
 		return nil
 	}
 
-	return newPathError("MkdirAll", path, status)
+	return NewPathError("MkdirAll", path, status)
 }
 
 // Rename moves a file from A to B
@@ -336,7 +333,7 @@ func (c *Client) Read(path string) ([]byte, error) {
 func (c *Client) ReadStream(path string) (io.ReadCloser, error) {
 	rs, err := c.req("GET", path, nil, nil)
 	if err != nil {
-		return nil, newPathErrorErr("ReadStream", path, err)
+		return nil, NewPathErrorErr("ReadStream", path, err)
 	}
 
 	if rs.StatusCode == 200 {
@@ -344,7 +341,7 @@ func (c *Client) ReadStream(path string) (io.ReadCloser, error) {
 	}
 
 	rs.Body.Close()
-	return nil, newPathError("ReadStream", path, rs.StatusCode)
+	return nil, NewPathError("ReadStream", path, rs.StatusCode)
 }
 
 // ReadStreamRange reads the stream representing a subset of bytes for a given path,
@@ -357,10 +354,14 @@ func (c *Client) ReadStream(path string) (io.ReadCloser, error) {
 // to `length`.
 func (c *Client) ReadStreamRange(path string, offset, length int64) (io.ReadCloser, error) {
 	rs, err := c.req("GET", path, nil, func(r *http.Request) {
-		r.Header.Add("Range", fmt.Sprintf("bytes=%v-%v", offset, offset+length-1))
+		if length > 0 {
+			r.Header.Add("Range", fmt.Sprintf("bytes=%d-%d", offset, offset+length-1))
+		} else {
+			r.Header.Add("Range", fmt.Sprintf("bytes=%d-", offset))
+		}
 	})
 	if err != nil {
-		return nil, newPathErrorErr("ReadStreamRange", path, err)
+		return nil, NewPathErrorErr("ReadStreamRange", path, err)
 	}
 
 	if rs.StatusCode == http.StatusPartialContent {
@@ -373,55 +374,65 @@ func (c *Client) ReadStreamRange(path string, offset, length int64) (io.ReadClos
 	if rs.StatusCode == 200 {
 		// discard first 'offset' bytes.
 		if _, err := io.Copy(io.Discard, io.LimitReader(rs.Body, offset)); err != nil {
-			return nil, newPathErrorErr("ReadStreamRange", path, err)
+			return nil, NewPathErrorErr("ReadStreamRange", path, err)
 		}
 
 		// return a io.ReadCloser that is limited to `length` bytes.
-		return &limitedReadCloser{rs.Body, int(length)}, nil
+		return &limitedReadCloser{rc: rs.Body, remaining: int(length)}, nil
 	}
 
 	rs.Body.Close()
-	return nil, newPathError("ReadStream", path, rs.StatusCode)
+	return nil, NewPathError("ReadStream", path, rs.StatusCode)
 }
 
 // Write writes data to a given path
-func (c *Client) Write(path string, data []byte, _ os.FileMode) error {
+func (c *Client) Write(path string, data []byte, _ os.FileMode) (err error) {
-	s := c.put(path, bytes.NewReader(data))
+	s, err := c.put(path, bytes.NewReader(data))
+	if err != nil {
+		return
+	}
+
 	switch s {
 
 	case 200, 201, 204:
 		return nil
 
-	case 409:
+	case 404, 409:
-		err := c.createParentCollection(path)
+		err = c.createParentCollection(path)
 		if err != nil {
-			return err
+			return
 		}
 
-		s = c.put(path, bytes.NewReader(data))
+		s, err = c.put(path, bytes.NewReader(data))
+		if err != nil {
+			return
+		}
 		if s == 200 || s == 201 || s == 204 {
-			return nil
+			return
 		}
 	}
 
-	return newPathError("Write", path, s)
+	return NewPathError("Write", path, s)
 }
 
 // WriteStream writes a stream
-func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) error {
+func (c *Client) WriteStream(path string, stream io.Reader, _ os.FileMode) (err error) {
 
-	err := c.createParentCollection(path)
+	err = c.createParentCollection(path)
 	if err != nil {
 		return err
 	}
 
-	s := c.put(path, stream)
+	s, err := c.put(path, stream)
+	if err != nil {
+		return err
+	}
 
 	switch s {
 	case 200, 201, 204:
 		return nil
 
 	default:
-		return newPathError("WriteStream", path, s)
+		return NewPathError("WriteStream", path, s)
 	}
 }

client_test.go

@@ -0,0 +1,574 @@
+package gowebdav
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"golang.org/x/net/webdav"
+)
+
+func noAuthHndl(h http.Handler) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		h.ServeHTTP(w, r)
+	}
+}
+
+func basicAuth(h http.Handler) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if user, passwd, ok := r.BasicAuth(); ok {
+			if user == "user" && passwd == "password" {
+				h.ServeHTTP(w, r)
+				return
+			}
+
+			http.Error(w, "not authorized", 403)
+		} else {
+			w.Header().Set("WWW-Authenticate", `Basic realm="x"`)
+			w.WriteHeader(401)
+		}
+	}
+}
+
+func multipleAuth(h http.Handler) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		notAuthed := false
+		if r.Header.Get("Authorization") == "" {
+			notAuthed = true
+		} else if user, passwd, ok := r.BasicAuth(); ok {
+			if user == "user" && passwd == "password" {
+				h.ServeHTTP(w, r)
+				return
+			}
+			notAuthed = true
+		} else if strings.HasPrefix(r.Header.Get("Authorization"), "Digest ") {
+			pairs := strings.TrimPrefix(r.Header.Get("Authorization"), "Digest ")
+			digestParts := make(map[string]string)
+			for _, pair := range strings.Split(pairs, ",") {
+				kv := strings.SplitN(strings.TrimSpace(pair), "=", 2)
+				key, value := kv[0], kv[1]
+				value = strings.Trim(value, `"`)
+				digestParts[key] = value
+			}
+			if digestParts["qop"] == "" {
+				digestParts["qop"] = "auth"
+			}
+
+			ha1 := getMD5(fmt.Sprint(digestParts["username"], ":", digestParts["realm"], ":", "digestPW"))
+			ha2 := getMD5(fmt.Sprint(r.Method, ":", digestParts["uri"]))
+			expected := getMD5(fmt.Sprint(ha1,
+				":", digestParts["nonce"],
+				":", digestParts["nc"],
+				":", digestParts["cnonce"],
+				":", digestParts["qop"],
+				":", ha2))
+
+			if expected == digestParts["response"] {
+				h.ServeHTTP(w, r)
+				return
+			}
+			notAuthed = true
+		}
+
+		if notAuthed {
+			w.Header().Add("WWW-Authenticate", `Digest realm="testrealm@host.com", qop="auth,auth-int",nonce="dcd98b7102dd2f0e8b11d0f600bfb0c093",opaque="5ccc069c403ebaf9f0171e9517f40e41"`)
+			w.Header().Add("WWW-Authenticate", `Basic realm="x"`)
+			w.WriteHeader(401)
+		}
+	}
+}
+
+func fillFs(t *testing.T, fs webdav.FileSystem) context.Context {
+	ctx := context.Background()
+	f, err := fs.OpenFile(ctx, "hello.txt", os.O_CREATE, 0644)
+	if err != nil {
+		t.Errorf("fail to crate file: %v", err)
+	}
+	f.Write([]byte("hello gowebdav\n"))
+	f.Close()
+	err = fs.Mkdir(ctx, "/test", 0755)
+	if err != nil {
+		t.Errorf("fail to crate directory: %v", err)
+	}
+	f, err = fs.OpenFile(ctx, "/test/test.txt", os.O_CREATE, 0644)
+	if err != nil {
+		t.Errorf("fail to crate file: %v", err)
+	}
+	f.Write([]byte("test test gowebdav\n"))
+	f.Close()
+	return ctx
+}
+
+func newServer(t *testing.T) (*Client, *httptest.Server, webdav.FileSystem, context.Context) {
+	return newAuthServer(t, basicAuth)
+}
+
+func newAuthServer(t *testing.T, auth func(h http.Handler) http.HandlerFunc) (*Client, *httptest.Server, webdav.FileSystem, context.Context) {
+	srv, fs, ctx := newAuthSrv(t, auth)
+	cli := NewClient(srv.URL, "user", "password")
+	return cli, srv, fs, ctx
+}
+
+func newAuthSrv(t *testing.T, auth func(h http.Handler) http.HandlerFunc) (*httptest.Server, webdav.FileSystem, context.Context) {
+	mux := http.NewServeMux()
+	fs := webdav.NewMemFS()
+	ctx := fillFs(t, fs)
+	mux.HandleFunc("/", auth(&webdav.Handler{
+		FileSystem: fs,
+		LockSystem: webdav.NewMemLS(),
+	}))
+	srv := httptest.NewServer(mux)
+	return srv, fs, ctx
+}
+
+func TestConnect(t *testing.T) {
+	cli, srv, _, _ := newServer(t)
+	defer srv.Close()
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got error: %v, want nil", err)
+	}
+
+	cli = NewClient(srv.URL, "no", "no")
+	if err := cli.Connect(); err == nil {
+		t.Fatalf("got nil, want error: %v", err)
+	}
+}
+
+func TestConnectMultipleAuth(t *testing.T) {
+	cli, srv, _, _ := newAuthServer(t, multipleAuth)
+	defer srv.Close()
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got error: %v, want nil", err)
+	}
+
+	cli = NewClient(srv.URL, "digestUser", "digestPW")
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got nil, want error: %v", err)
+	}
+
+	cli = NewClient(srv.URL, "no", "no")
+	if err := cli.Connect(); err == nil {
+		t.Fatalf("got nil, want error: %v", err)
+	}
+}
+
+func TestConnectMultiAuthII(t *testing.T) {
+	cli, srv, _, _ := newAuthServer(t, func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			if user, passwd, ok := r.BasicAuth(); ok {
+				if user == "user" && passwd == "password" {
+					h.ServeHTTP(w, r)
+					return
+				}
+
+				http.Error(w, "not authorized", 403)
+			} else {
+				w.Header().Add("WWW-Authenticate", `FooAuth`)
+				w.Header().Add("WWW-Authenticate", `BazAuth`)
+				w.Header().Add("WWW-Authenticate", `BarAuth`)
+				w.Header().Add("WWW-Authenticate", `Basic realm="x"`)
+				w.WriteHeader(401)
+			}
+		}
+	})
+	defer srv.Close()
+	if err := cli.Connect(); err != nil {
+		t.Fatalf("got error: %v, want nil", err)
+	}
+
+	cli = NewClient(srv.URL, "no", "no")
+	if err := cli.Connect(); err == nil {
+		t.Fatalf("got nil, want error: %v", err)
+	}
+}
+
+func TestReadDirConcurrent(t *testing.T) {
+	cli, srv, _, _ := newServer(t)
+	defer srv.Close()
+
+	var wg sync.WaitGroup
+	errs := make(chan error, 2)
+	for i := 0; i < 2; i++ {
+		wg.Add(1)
+
+		go func() {
+			defer wg.Done()
+			f, err := cli.ReadDir("/")
+			if err != nil {
+				errs <- errors.New(fmt.Sprintf("got error: %v, want file listing: %v", err, f))
+			}
+			if len(f) != 2 {
+				errs <- errors.New(fmt.Sprintf("f: %v err: %v", f, err))
+			}
+			if f[0].Name() != "hello.txt" && f[1].Name() != "hello.txt" {
+				errs <- errors.New(fmt.Sprintf("got: %v, want file: %s", f, "hello.txt"))
+			}
+			if f[0].Name() != "test" && f[1].Name() != "test" {
+				errs <- errors.New(fmt.Sprintf("got: %v, want directory: %s", f, "test"))
+			}
+		}()
+	}
+
+	wg.Wait()
+	close(errs)
+
+	for err := range errs {
+		if err != nil {
+			t.Fatal(err)
+		}
+	}
+}
+
+func TestRead(t *testing.T) {
+	cli, srv, _, _ := newServer(t)
+	defer srv.Close()
+
+	data, err := cli.Read("/hello.txt")
+	if err != nil || bytes.Compare(data, []byte("hello gowebdav\n")) != 0 {
+		t.Fatalf("got: %v, want data: %s", err, []byte("hello gowebdav\n"))
+	}
+
+	data, err = cli.Read("/404.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", data, err)
+	}
+	if !IsErrNotFound(err) {
+		t.Fatalf("got: %v, want 404 error", err)
+	}
+}
+
+func TestReadNoAuth(t *testing.T) {
+	cli, srv, _, _ := newAuthServer(t, noAuthHndl)
+	defer srv.Close()
+
+	data, err := cli.Read("/hello.txt")
+	if err != nil || bytes.Compare(data, []byte("hello gowebdav\n")) != 0 {
+		t.Fatalf("got: %v, want data: %s", err, []byte("hello gowebdav\n"))
+	}
+
+	data, err = cli.Read("/404.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", data, err)
+	}
+	if !IsErrNotFound(err) {
+		t.Fatalf("got: %v, want 404 error", err)
+	}
+}
+
+func TestReadStream(t *testing.T) {
+	cli, srv, _, _ := newServer(t)
+	defer srv.Close()
+
+	stream, err := cli.ReadStream("/hello.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want data: %v", err, stream)
+	}
+	buf := new(bytes.Buffer)
+	buf.ReadFrom(stream)
+	if buf.String() != "hello gowebdav\n" {
+		t.Fatalf("got: %v, want stream: hello gowebdav", buf.String())
+	}
+
+	stream, err = cli.ReadStream("/404/hello.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", stream, err)
+	}
+}
+
+func TestReadStreamRange(t *testing.T) {
+	cli, srv, _, _ := newServer(t)
+	defer srv.Close()
+
+	stream, err := cli.ReadStreamRange("/hello.txt", 4, 4)
+	if err != nil {
+		t.Fatalf("got: %v, want data: %v", err, stream)
+	}
+	buf := new(bytes.Buffer)
+	buf.ReadFrom(stream)
+	if buf.String() != "o go" {
+		t.Fatalf("got: %v, want stream: o go", buf.String())
+	}
+
+	stream, err = cli.ReadStream("/404/hello.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", stream, err)
+	}
+}
+
+func TestReadStreamRangeUnkownLength(t *testing.T) {
+	cli, srv, _, _ := newServer(t)
+	defer srv.Close()
+
+	stream, err := cli.ReadStreamRange("/hello.txt", 6, 0)
+	if err != nil {
+		t.Fatalf("got: %v, want data: %v", err, stream)
+	}
+	buf := new(bytes.Buffer)
+	buf.ReadFrom(stream)
+	if buf.String() != "gowebdav\n" {
+		t.Fatalf("got: %v, want stream: gowebdav\n", buf.String())
+	}
+
+	stream, err = cli.ReadStream("/404/hello.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", stream, err)
+	}
+}
+
+func TestStat(t *testing.T) {
+	cli, srv, _, _ := newServer(t)
+	defer srv.Close()
+
+	info, err := cli.Stat("/hello.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want os.Info: %v", err, info)
+	}
+	if info.Name() != "hello.txt" {
+		t.Fatalf("got: %v, want file hello.txt", info)
+	}
+
+	info, err = cli.Stat("/404.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", info, err)
+	}
+	if !IsErrNotFound(err) {
+		t.Fatalf("got: %v, want 404 error", err)
+	}
+}
+
+func TestMkdir(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	info, err := cli.Stat("/newdir")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", info, err)
+	}
+
+	if err := cli.Mkdir("/newdir", 0755); err != nil {
+		t.Fatalf("got: %v, want mkdir /newdir", err)
+	}
+
+	if err := cli.Mkdir("/newdir", 0755); err != nil {
+		t.Fatalf("got: %v, want mkdir /newdir", err)
+	}
+
+	info, err = fs.Stat(ctx, "/newdir")
+	if err != nil {
+		t.Fatalf("got: %v, want dir info: %v", err, info)
+	}
+
+	if err := cli.Mkdir("/404/newdir", 0755); err == nil {
+		t.Fatalf("expected Mkdir error due to missing parent directory")
+	}
+}
+
+func TestMkdirAll(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	if err := cli.MkdirAll("/dir/dir/dir", 0755); err != nil {
+		t.Fatalf("got: %v, want mkdirAll /dir/dir/dir", err)
+	}
+
+	info, err := fs.Stat(ctx, "/dir/dir/dir")
+	if err != nil {
+		t.Fatalf("got: %v, want dir info: %v", err, info)
+	}
+}
+
+func TestCopy(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	info, err := fs.Stat(ctx, "/copy.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", info, err)
+	}
+
+	if err := cli.Copy("/hello.txt", "/copy.txt", false); err != nil {
+		t.Fatalf("got: %v, want copy /hello.txt to /copy.txt", err)
+	}
+
+	info, err = fs.Stat(ctx, "/copy.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want file info: %v", err, info)
+	}
+	if info.Size() != 15 {
+		t.Fatalf("got: %v, want file size: %d bytes", info.Size(), 15)
+	}
+
+	info, err = fs.Stat(ctx, "/hello.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want file info: %v", err, info)
+	}
+	if info.Size() != 15 {
+		t.Fatalf("got: %v, want file size: %d bytes", info.Size(), 15)
+	}
+
+	if err := cli.Copy("/hello.txt", "/copy.txt", false); err == nil {
+		t.Fatalf("expected copy error due to overwrite false")
+	}
+
+	if err := cli.Copy("/hello.txt", "/copy.txt", true); err != nil {
+		t.Fatalf("got: %v, want overwrite /copy.txt with /hello.txt", err)
+	}
+}
+
+func TestRename(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	info, err := fs.Stat(ctx, "/copy.txt")
+	if err == nil {
+		t.Fatalf("got: %v, want error: %v", info, err)
+	}
+
+	if err := cli.Rename("/hello.txt", "/copy.txt", false); err != nil {
+		t.Fatalf("got: %v, want mv /hello.txt to /copy.txt", err)
+	}
+
+	info, err = fs.Stat(ctx, "/copy.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want file info: %v", err, info)
+	}
+	if info.Size() != 15 {
+		t.Fatalf("got: %v, want file size: %d bytes", info.Size(), 15)
+	}
+
+	if info, err = fs.Stat(ctx, "/hello.txt"); err == nil {
+		t.Fatalf("got: %v, want error: %v", info, err)
+	}
+
+	if err := cli.Rename("/test/test.txt", "/copy.txt", true); err != nil {
+		t.Fatalf("got: %v, want overwrite /copy.txt with /hello.txt", err)
+	}
+	info, err = fs.Stat(ctx, "/copy.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want file info: %v", err, info)
+	}
+	if info.Size() != 19 {
+		t.Fatalf("got: %v, want file size: %d bytes", info.Size(), 19)
+	}
+}
+
+func TestRemove(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	if err := cli.Remove("/hello.txt"); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+
+	if info, err := fs.Stat(ctx, "/hello.txt"); err == nil {
+		t.Fatalf("got: %v, want error: %v", info, err)
+	}
+
+	if err := cli.Remove("/404.txt"); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+}
+
+func TestRemoveAll(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	if err := cli.RemoveAll("/test/test.txt"); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+
+	if info, err := fs.Stat(ctx, "/test/test.txt"); err == nil {
+		t.Fatalf("got: %v, want error: %v", info, err)
+	}
+
+	if err := cli.RemoveAll("/404.txt"); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+
+	if err := cli.RemoveAll("/404/404/404.txt"); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+}
+
+func TestWrite(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	if err := cli.Write("/newfile.txt", []byte("foo bar\n"), 0660); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+
+	info, err := fs.Stat(ctx, "/newfile.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want file info: %v", err, info)
+	}
+	if info.Size() != 8 {
+		t.Fatalf("got: %v, want file size: %d bytes", info.Size(), 8)
+	}
+
+	if err := cli.Write("/404/newfile.txt", []byte("foo bar\n"), 0660); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+}
+
+func TestWriteStream(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	if err := cli.WriteStream("/newfile.txt", strings.NewReader("foo bar\n"), 0660); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+
+	info, err := fs.Stat(ctx, "/newfile.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want file info: %v", err, info)
+	}
+	if info.Size() != 8 {
+		t.Fatalf("got: %v, want file size: %d bytes", info.Size(), 8)
+	}
+
+	if err := cli.WriteStream("/404/works.txt", strings.NewReader("foo bar\n"), 0660); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+
+	if info, err := fs.Stat(ctx, "/404/works.txt"); err != nil {
+		t.Fatalf("got: %v, want file info: %v", err, info)
+	}
+}
+
+func TestWriteStreamFromPipe(t *testing.T) {
+	cli, srv, fs, ctx := newServer(t)
+	defer srv.Close()
+
+	r, w := io.Pipe()
+
+	go func() {
+		defer w.Close()
+		fmt.Fprint(w, "foo")
+		time.Sleep(1 * time.Second)
+		fmt.Fprint(w, " ")
+		time.Sleep(1 * time.Second)
+		fmt.Fprint(w, "bar\n")
+	}()
+
+	if err := cli.WriteStream("/newfile.txt", r, 0660); err != nil {
+		t.Fatalf("got: %v, want nil", err)
+	}
+
+	info, err := fs.Stat(ctx, "/newfile.txt")
+	if err != nil {
+		t.Fatalf("got: %v, want file info: %v", err, info)
+	}
+	if info.Size() != 8 {
+		t.Fatalf("got: %v, want file size: %d bytes", info.Size(), 8)
+	}
+}

cmd/gowebdav/main.go

@@ -4,13 +4,16 @@ import (
 	"errors"
 	"flag"
 	"fmt"
-	d "github.com/studio-b12/gowebdav"
 	"io"
+	"io/fs"
 	"os"
 	"os/user"
+	"path"
 	"path/filepath"
 	"runtime"
 	"strings"
+
+	d "git.siteop.biz/shoopea/gowebdav"
 )
 
 func main() {
@@ -52,6 +55,10 @@ func main() {
 
 	c := d.NewClient(*root, *user, *password)
 
+	if e := c.Connect(); e != nil {
+		panic(e)
+	}
+
 	cmd := getCmd(*method)
 
 	if e := cmd(c, flag.Arg(0), flag.Arg(1)); e != nil {
@@ -190,8 +197,18 @@ func cmdCp(c *d.Client, p0, p1 string) (err error) {
 
 func cmdPut(c *d.Client, p0, p1 string) (err error) {
 	if p1 == "" {
-		p1 = filepath.Join(".", p0)
+		p1 = path.Join(".", p0)
+	} else {
+		var fi fs.FileInfo
+		fi, err = c.Stat(p0)
+		if err != nil && !d.IsErrNotFound(err) {
+			return
+		}
+		if !d.IsErrNotFound(err) && fi.IsDir() {
+			p0 = path.Join(p0, p1)
+		}
 	}
+
 	stream, err := getStream(p1)
 	if err != nil {
 		return

digestAuth.go

@@ -17,28 +17,46 @@ type DigestAuth struct {
 	digestParts map[string]string
 }
 
-// Type identifies the DigestAuthenticator
+// NewDigestAuth creates a new instance of our Digest Authenticator
-func (d *DigestAuth) Type() string {
+func NewDigestAuth(login, secret string, rs *http.Response) (Authenticator, error) {
-	return "DigestAuth"
+	return &DigestAuth{user: login, pw: secret, digestParts: digestParts(rs)}, nil
-}
-
-// User holds the DigestAuth username
-func (d *DigestAuth) User() string {
-	return d.user
-}
-
-// Pass holds the DigestAuth password
-func (d *DigestAuth) Pass() string {
-	return d.pw
 }
 
 // Authorize the current request
-func (d *DigestAuth) Authorize(req *http.Request, method string, path string) {
+func (d *DigestAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
 	d.digestParts["uri"] = path
-	d.digestParts["method"] = method
+	d.digestParts["method"] = rq.Method
 	d.digestParts["username"] = d.user
 	d.digestParts["password"] = d.pw
-	req.Header.Set("Authorization", getDigestAuthorization(d.digestParts))
+	rq.Header.Set("Authorization", getDigestAuthorization(d.digestParts))
+	return nil
+}
+
+// Verify checks for authentication issues and may trigger a re-authentication
+func (d *DigestAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	if rs.StatusCode == 401 {
+		err = NewPathError("Authorize", path, rs.StatusCode)
+	}
+	return
+}
+
+// Close cleans up all resources
+func (d *DigestAuth) Close() error {
+	return nil
+}
+
+// Clone creates a copy of itself
+func (d *DigestAuth) Clone() Authenticator {
+	parts := make(map[string]string, len(d.digestParts))
+	for k, v := range d.digestParts {
+		parts[k] = v
+	}
+	return &DigestAuth{user: d.user, pw: d.pw, digestParts: parts}
+}
+
+// String toString
+func (d *DigestAuth) String() string {
+	return fmt.Sprintf("DigestAuth login: %s", d.user)
 }
 
 func digestParts(resp *http.Response) map[string]string {

digestAuth_test.go

@@ -0,0 +1,35 @@
+package gowebdav
+
+import (
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestNewDigestAuth(t *testing.T) {
+	a := &DigestAuth{user: "user", pw: "password", digestParts: make(map[string]string, 0)}
+
+	ex := "DigestAuth login: user"
+	if a.String() != ex {
+		t.Error("expected: " + ex + " got: " + a.String())
+	}
+
+	if a.Clone() == a {
+		t.Error("expected a different instance")
+	}
+
+	if a.Close() != nil {
+		t.Error("expected close without errors")
+	}
+}
+
+func TestDigestAuthAuthorize(t *testing.T) {
+	a := &DigestAuth{user: "user", pw: "password", digestParts: make(map[string]string, 0)}
+	rq, _ := http.NewRequest("GET", "http://localhost/", nil)
+	a.Authorize(nil, rq, "/")
+	// TODO this is a very lazy test it cuts of cnonce
+	ex := `Digest username="user", realm="", nonce="", uri="/", nc=1, cnonce="`
+	if strings.Index(rq.Header.Get("Authorization"), ex) != 0 {
+		t.Error("got wrong Authorization header: " + rq.Header.Get("Authorization"))
+	}
+}

errors.go

@@ -0,0 +1,57 @@
+package gowebdav
+
+import (
+	"errors"
+	"fmt"
+	"os"
+)
+
+// ErrAuthChanged must be returned from the Verify method as an error
+// to trigger a re-authentication / negotiation with a new authenticator.
+var ErrAuthChanged = errors.New("authentication failed, change algorithm")
+
+// ErrTooManyRedirects will be used as return error if a request exceeds 10 redirects.
+var ErrTooManyRedirects = errors.New("stopped after 10 redirects")
+
+// StatusError implements error and wraps
+// an erroneous status code.
+type StatusError struct {
+	Status int
+}
+
+func (se StatusError) Error() string {
+	return fmt.Sprintf("%d", se.Status)
+}
+
+// IsErrCode returns true if the given error
+// is an os.PathError wrapping a StatusError
+// with the given status code.
+func IsErrCode(err error, code int) bool {
+	if pe, ok := err.(*os.PathError); ok {
+		se, ok := pe.Err.(StatusError)
+		return ok && se.Status == code
+	}
+	return false
+}
+
+// IsErrNotFound is shorthand for IsErrCode
+// for status 404.
+func IsErrNotFound(err error) bool {
+	return IsErrCode(err, 404)
+}
+
+func NewPathError(op string, path string, statusCode int) error {
+	return &os.PathError{
+		Op:   op,
+		Path: path,
+		Err:  StatusError{statusCode},
+	}
+}
+
+func NewPathErrorErr(op string, path string, err error) error {
+	return &os.PathError{
+		Op:   op,
+		Path: path,
+		Err:  err,
+	}
+}

go.mod

@@ -1,3 +1,3 @@
-module github.com/studio-b12/gowebdav
+module git.siteop.biz/shoopea/gowebdav
 
 go 1.17

go_test.mod

@@ -0,0 +1,5 @@
+module github.com/studio-b12/gowebdav
+
+go 1.17
+
+require golang.org/x/net v0.0.0-20221014081412-f15817d10f9b

go_test.sum

@@ -0,0 +1,7 @@
+golang.org/x/net v0.0.0-20221014081412-f15817d10f9b h1:tvrvnPFcdzp294diPnrdZZZ8XUt2Tyj7svb7X52iDuU=
+golang.org/x/net v0.0.0-20221014081412-f15817d10f9b/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220728004956-3c1f35247d10/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=

passportAuth.go

@@ -0,0 +1,181 @@
+package gowebdav
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+// PassportAuth structure holds our credentials
+type PassportAuth struct {
+	user            string
+	pw              string
+	cookies         []http.Cookie
+	inhibitRedirect bool
+}
+
+// constructor for PassportAuth creates a new PassportAuth object and
+// automatically authenticates against the given partnerURL
+func NewPassportAuth(c *http.Client, user, pw, partnerURL string, header *http.Header) (Authenticator, error) {
+	p := &PassportAuth{
+		user:            user,
+		pw:              pw,
+		inhibitRedirect: true,
+	}
+	err := p.genCookies(c, partnerURL, header)
+	return p, err
+}
+
+// Authorize the current request
+func (p *PassportAuth) Authorize(c *http.Client, rq *http.Request, path string) error {
+	// prevent redirects to detect subsequent authentication requests
+	if p.inhibitRedirect {
+		rq.Header.Set(XInhibitRedirect, "1")
+	} else {
+		p.inhibitRedirect = true
+	}
+	for _, cookie := range p.cookies {
+		rq.AddCookie(&cookie)
+	}
+	return nil
+}
+
+// Verify verifies if the authentication is good
+func (p *PassportAuth) Verify(c *http.Client, rs *http.Response, path string) (redo bool, err error) {
+	switch rs.StatusCode {
+	case 301, 302, 307, 308:
+		redo = true
+		if rs.Header.Get("Www-Authenticate") != "" {
+			// re-authentication required as we are redirected to the login page
+			err = p.genCookies(c, rs.Request.URL.String(), &rs.Header)
+		} else {
+			// just a redirect, follow it
+			p.inhibitRedirect = false
+		}
+	case 401:
+		err = NewPathError("Authorize", path, rs.StatusCode)
+	}
+	return
+}
+
+// Close cleans up all resources
+func (p *PassportAuth) Close() error {
+	return nil
+}
+
+// Clone creates a Copy of itself
+func (p *PassportAuth) Clone() Authenticator {
+	// create a copy to allow independent cookie updates
+	clonedCookies := make([]http.Cookie, len(p.cookies))
+	copy(clonedCookies, p.cookies)
+
+	return &PassportAuth{
+		user:            p.user,
+		pw:              p.pw,
+		cookies:         clonedCookies,
+		inhibitRedirect: true,
+	}
+}
+
+// String toString
+func (p *PassportAuth) String() string {
+	return fmt.Sprintf("PassportAuth login: %s", p.user)
+}
+
+func (p *PassportAuth) genCookies(c *http.Client, partnerUrl string, header *http.Header) error {
+	// For more details refer to:
+	// https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-pass/2c80637d-438c-4d4b-adc5-903170a779f3
+	// Skipping step 1 and 2 as we already have the partner server challenge
+
+	baseAuthenticationServer := header.Get("Location")
+	baseAuthenticationServerURL, err := url.Parse(baseAuthenticationServer)
+	if err != nil {
+		return err
+	}
+
+	// Skipping step 3 and 4 as we already know that we need and have the user's credentials
+	// Step 5 (Sign-in request)
+	authenticationServerUrl := url.URL{
+		Scheme: baseAuthenticationServerURL.Scheme,
+		Host:   baseAuthenticationServerURL.Host,
+		Path:   "/login2.srf",
+	}
+
+	partnerServerChallenge := strings.Split(header.Get("Www-Authenticate"), " ")[1]
+
+	req := http.Request{
+		Method: "GET",
+		URL:    &authenticationServerUrl,
+		Header: http.Header{
+			"Authorization": []string{"Passport1.4 sign-in=" + url.QueryEscape(p.user) + ",pwd=" + url.QueryEscape(p.pw) + ",OrgVerb=GET,OrgUrl=" + partnerUrl + "," + partnerServerChallenge},
+		},
+	}
+
+	rs, err := c.Do(&req)
+	if err != nil {
+		return err
+	}
+	io.Copy(io.Discard, rs.Body)
+	rs.Body.Close()
+	if rs.StatusCode != 200 {
+		return NewPathError("Authorize", "/", rs.StatusCode)
+	}
+
+	// Step 6 (Token Response from Authentication Server)
+	tokenResponseHeader := rs.Header.Get("Authentication-Info")
+	if tokenResponseHeader == "" {
+		return NewPathError("Authorize", "/", 401)
+	}
+	tokenResponseHeaderList := strings.Split(tokenResponseHeader, ",")
+	token := ""
+	for _, tokenResponseHeader := range tokenResponseHeaderList {
+		if strings.HasPrefix(tokenResponseHeader, "from-PP='") {
+			token = tokenResponseHeader
+			break
+		}
+	}
+	if token == "" {
+		return NewPathError("Authorize", "/", 401)
+	}
+
+	// Step 7 (First Authentication Request to Partner Server)
+	origUrl, err := url.Parse(partnerUrl)
+	if err != nil {
+		return err
+	}
+	req = http.Request{
+		Method: "GET",
+		URL:    origUrl,
+		Header: http.Header{
+			"Authorization": []string{"Passport1.4 " + token},
+		},
+	}
+
+	rs, err = c.Do(&req)
+	if err != nil {
+		return err
+	}
+	io.Copy(io.Discard, rs.Body)
+	rs.Body.Close()
+	if rs.StatusCode != 200 && rs.StatusCode != 302 {
+		return NewPathError("Authorize", "/", rs.StatusCode)
+	}
+
+	// Step 8 (Set Token Message from Partner Server)
+	cookies := rs.Header.Values("Set-Cookie")
+	p.cookies = make([]http.Cookie, len(cookies))
+	for i, cookie := range cookies {
+		cookieParts := strings.Split(cookie, ";")
+		cookieName := strings.Split(cookieParts[0], "=")[0]
+		cookieValue := strings.Split(cookieParts[0], "=")[1]
+
+		p.cookies[i] = http.Cookie{
+			Name:  cookieName,
+			Value: cookieValue,
+		}
+	}
+
+	return nil
+}

passportAuth_test.go

@@ -0,0 +1,66 @@
+package gowebdav
+
+import (
+	"bytes"
+	"net/http"
+	"net/url"
+	"regexp"
+	"testing"
+)
+
+// testing the creation is enough as it handles the authorization during init
+func TestNewPassportAuth(t *testing.T) {
+	user := "user"
+	pass := "password"
+	p1 := "some,comma,separated,values"
+	token := "from-PP='token'"
+
+	authHandler := func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			reg, err := regexp.Compile("Passport1\\.4 sign-in=" + url.QueryEscape(user) + ",pwd=" + url.QueryEscape(pass) + ",OrgVerb=GET,OrgUrl=.*," + p1)
+			if err != nil {
+				t.Error(err)
+			}
+			if reg.MatchString(r.Header.Get("Authorization")) {
+				w.Header().Set("Authentication-Info", token)
+				w.WriteHeader(200)
+				return
+			}
+		}
+	}
+	authsrv, _, _ := newAuthSrv(t, authHandler)
+	defer authsrv.Close()
+
+	dataHandler := func(h http.Handler) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			reg, err := regexp.Compile("Passport1\\.4 " + token)
+			if err != nil {
+				t.Error(err)
+			}
+			if reg.MatchString(r.Header.Get("Authorization")) {
+				w.Header().Set("Set-Cookie", "Pass=port")
+				h.ServeHTTP(w, r)
+				return
+			}
+			for _, c := range r.Cookies() {
+				if c.Name == "Pass" && c.Value == "port" {
+					h.ServeHTTP(w, r)
+					return
+				}
+			}
+			w.Header().Set("Www-Authenticate", "Passport1.4 "+p1)
+			http.Redirect(w, r, authsrv.URL+"/", 302)
+		}
+	}
+	srv, _, _ := newAuthSrv(t, dataHandler)
+	defer srv.Close()
+
+	cli := NewClient(srv.URL, user, pass)
+	data, err := cli.Read("/hello.txt")
+	if err != nil {
+		t.Errorf("got error=%v; want nil", err)
+	}
+	if !bytes.Equal(data, []byte("hello gowebdav\n")) {
+		t.Logf("got data=%v; want=hello gowebdav", data)
+	}
+}

requests.go

@@ -1,117 +1,77 @@
 package gowebdav
 
 import (
-	"bytes"
-	"fmt"
 	"io"
+	"log"
 	"net/http"
 	"path"
 	"strings"
 )
 
-func (c *Client) req(method, path string, body io.Reader, intercept func(*http.Request)) (req *http.Response, err error) {
+func (c *Client) req(method, path string, body io.Reader, intercept func(*http.Request)) (rs *http.Response, err error) {
+	var redo bool
 	var r *http.Request
-	var retryBuf io.Reader
+	var uri = PathEscape(Join(c.root, path))
+	auth, body := c.auth.NewAuthenticator(body)
+	defer auth.Close()
 
-	if body != nil {
+	for { // TODO auth.continue() strategy(true|n times|until)?
-		// Because Request#Do closes closable streams, Seeker#Seek
+		if r, err = http.NewRequest(method, uri, body); err != nil {
-		// will fail on retry because stream is already  closed.
+			return
-		// This inhibits the closing of the passed stream on passing
-		// it to the RoundTripper and closes the stream after we
-		// are done with the body content.
-		if cl, ok := body.(io.Closer); ok {
-			body = closeInhibitor{body}
-			defer cl.Close()
 		}
-		// If the authorization fails, we will need to restart reading
+
-		// from the passed body stream.
+		for k, vals := range c.headers {
-		// When body is seekable, use seek to reset the streams
+			for _, v := range vals {
-		// cursor to the start.
+				r.Header.Add(k, v)
-		// Otherwise, copy the stream into a buffer while uploading
-		// and use the buffers content on retry.
-		if sk, ok := body.(io.Seeker); ok {
-			if _, err = sk.Seek(0, io.SeekStart); err != nil {
-				return
 			}
-			retryBuf = body
-		} else {
-			buff := &bytes.Buffer{}
-			retryBuf = buff
-			body = io.TeeReader(body, buff)
-		}
-		r, err = http.NewRequest(method, PathEscape(Join(c.root, path)), body)
-	} else {
-		r, err = http.NewRequest(method, PathEscape(Join(c.root, path)), nil)
-	}
-
-	if err != nil {
-		return nil, err
-	}
-
-	for k, vals := range c.headers {
-		for _, v := range vals {
-			r.Header.Add(k, v)
-		}
-	}
-
-	// make sure we read 'c.auth' only once since it will be substituted below
-	// and that is unsafe to do when multiple goroutines are running at the same time.
-	c.authMutex.Lock()
-	auth := c.auth
-	c.authMutex.Unlock()
-
-	auth.Authorize(r, method, path)
-
-	if intercept != nil {
-		intercept(r)
-	}
-
-	if c.interceptor != nil {
-		c.interceptor(method, r)
-	}
-
-	rs, err := c.c.Do(r)
-	if err != nil {
-		return nil, err
-	}
-
-	if rs.StatusCode == 401 && auth.Type() == "NoAuth" {
-		wwwAuthenticateHeader := strings.ToLower(rs.Header.Get("Www-Authenticate"))
-
-		if strings.Index(wwwAuthenticateHeader, "digest") > -1 {
-			c.authMutex.Lock()
-			c.auth = &DigestAuth{auth.User(), auth.Pass(), digestParts(rs)}
-			c.authMutex.Unlock()
-		} else if strings.Index(wwwAuthenticateHeader, "basic") > -1 {
-			c.authMutex.Lock()
-			c.auth = &BasicAuth{auth.User(), auth.Pass()}
-			c.authMutex.Unlock()
-		} else {
-			return rs, newPathError("Authorize", c.root, rs.StatusCode)
 		}
 
-		// retryBuf will be nil if body was nil initially so no check
+		if err = auth.Authorize(c.c, r, path); err != nil {
-		// for body == nil is required here.
+			return
-		return c.req(method, path, retryBuf, intercept)
+		}
-	} else if rs.StatusCode == 401 {
+
-		return rs, newPathError("Authorize", c.root, rs.StatusCode)
+		if intercept != nil {
+			intercept(r)
+		}
+
+		if c.interceptor != nil {
+			c.interceptor(method, r)
+		}
+
+		if rs, err = c.c.Do(r); err != nil {
+			return
+		}
+
+		if redo, err = auth.Verify(c.c, rs, path); err != nil {
+			rs.Body.Close()
+			return nil, err
+		}
+		if redo {
+			rs.Body.Close()
+			if body, err = r.GetBody(); err != nil {
+				return nil, err
+			}
+			continue
+		}
+		break
 	}
 
 	return rs, err
 }
 
-func (c *Client) mkcol(path string) int {
+func (c *Client) mkcol(path string) (status int, err error) {
 	rs, err := c.req("MKCOL", path, nil, nil)
 	if err != nil {
-		return 400
+		return
 	}
 	defer rs.Body.Close()
 
-	if rs.StatusCode == 201 || rs.StatusCode == 405 {
+	status = rs.StatusCode
-		return 201
+	if status == 405 {
+		status = 201
 	}
 
-	return rs.StatusCode
+	return
 }
 
 func (c *Client) options(path string) (*http.Response, error) {
@@ -139,15 +99,24 @@ func (c *Client) propfind(path string, self bool, body string, resp interface{},
 	defer rs.Body.Close()
 
 	if rs.StatusCode != 207 {
-		return fmt.Errorf("%s - %s %s", rs.Status, "PROPFIND", path)
+		return NewPathError("PROPFIND", path, rs.StatusCode)
 	}
 
 	return parseXML(rs.Body, resp, parse)
 }
 
-func (c *Client) doCopyMove(method string, oldpath string, newpath string, overwrite bool) (int, io.ReadCloser) {
+func (c *Client) doCopyMove(
+	method string,
+	oldpath string,
+	newpath string,
+	overwrite bool,
+) (
+	status int,
+	r io.ReadCloser,
+	err error,
+) {
 	rs, err := c.req(method, oldpath, nil, func(rq *http.Request) {
-		rq.Header.Add("Destination", Join(c.root, newpath))
+		rq.Header.Add("Destination", PathEscape(Join(c.root, newpath)))
 		if overwrite {
 			rq.Header.Add("Overwrite", "T")
 		} else {
@@ -155,13 +124,18 @@ func (c *Client) doCopyMove(method string, oldpath string, newpath string, overw
 		}
 	})
 	if err != nil {
-		return 400, nil
+		return
 	}
-	return rs.StatusCode, rs.Body
+	status = rs.StatusCode
+	r = rs.Body
+	return
 }
 
-func (c *Client) copymove(method string, oldpath string, newpath string, overwrite bool) error {
+func (c *Client) copymove(method string, oldpath string, newpath string, overwrite bool) (err error) {
-	s, data := c.doCopyMove(method, oldpath, newpath, overwrite)
+	s, data, err := c.doCopyMove(method, oldpath, newpath, overwrite)
+	if err != nil {
+		return
+	}
 	if data != nil {
 		defer data.Close()
 	}
@@ -172,7 +146,7 @@ func (c *Client) copymove(method string, oldpath string, newpath string, overwri
 
 	case 207:
 		// TODO handle multistat errors, worst case ...
-		log(fmt.Sprintf(" TODO handle %s - %s multistatus result %s", method, oldpath, String(data)))
+		log.Printf("TODO handle %s - %s multistatus result %s\n", method, oldpath, String(data))
 
 	case 409:
 		err := c.createParentCollection(newpath)
@@ -183,17 +157,18 @@ func (c *Client) copymove(method string, oldpath string, newpath string, overwri
 		return c.copymove(method, oldpath, newpath, overwrite)
 	}
 
-	return newPathError(method, oldpath, s)
+	return NewPathError(method, oldpath, s)
 }
 
-func (c *Client) put(path string, stream io.Reader) int {
+func (c *Client) put(path string, stream io.Reader) (status int, err error) {
 	rs, err := c.req("PUT", path, stream, nil)
 	if err != nil {
-		return 400
+		return
 	}
 	defer rs.Body.Close()
 
-	return rs.StatusCode
+	status = rs.StatusCode
+	return
 }
 
 func (c *Client) createParentCollection(itemPath string) (err error) {

utils.go

@@ -3,35 +3,13 @@ package gowebdav
 import (
 	"bytes"
 	"encoding/xml"
-	"fmt"
 	"io"
 	"net/url"
-	"os"
 	"strconv"
 	"strings"
 	"time"
 )
 
-func log(msg interface{}) {
-	fmt.Println(msg)
-}
-
-func newPathError(op string, path string, statusCode int) error {
-	return &os.PathError{
-		Op:   op,
-		Path: path,
-		Err:  fmt.Errorf("%d", statusCode),
-	}
-}
-
-func newPathErrorErr(op string, path string, err error) error {
-	return &os.PathError{
-		Op:   op,
-		Path: path,
-		Err:  err,
-	}
-}
-
 // PathEscape escapes all segments of a given path
 func PathEscape(path string) string {
 	s := strings.Split(path, "/")
@@ -133,14 +111,3 @@ func (l *limitedReadCloser) Read(buf []byte) (int, error) {
 func (l *limitedReadCloser) Close() error {
 	return l.rc.Close()
 }
-
-// closeInhibitor implements io.Closer and
-// wraps a Reader. When Close() is performed
-// on it, it will simply be silently rejected.
-type closeInhibitor struct {
-	io.Reader
-}
-
-func (ci closeInhibitor) Close() error {
-	return nil
-}