plumbing/transport: http, Adds token authentication support [Fixes #858]

Signed-off-by: Eric Billingsley <ebilling@babrains.com>

Author: Eric Billingsley

Diff for: _examples/branch/main.go

@@ -28,7 +28,7 @@ func main() {
 
 	// Create a new plumbing.HashReference object with the name of the branch
 	// and the hash from the HEAD. The reference name should be a full reference
-	// name and now a abbreviated one, as is used on the git cli.
+	// name and not an abbreviated one, as is used on the git cli.
 	//
 	// For tags we should use `refs/tags/%s` instead of `refs/heads/%s` used
 	// for branches.

Diff for: plumbing/transport/http/common.go

@@ -201,6 +201,31 @@ func (a *BasicAuth) String() string {
 	return fmt.Sprintf("%s - %s:%s", a.Name(), a.Username, masked)
 }
 
+// TokenAuth implements the go-git http.AuthMethod and transport.AuthMethod interfaces
+type TokenAuth struct {
+	Token string
+}
+
+func (a *TokenAuth) setAuth(r *http.Request) {
+	if a == nil {
+		return
+	}
+	r.Header.Add("Authorization", fmt.Sprintf("Bearer %s", a.Token))
+}
+
+// Name is name of the auth
+func (a *TokenAuth) Name() string {
+	return "http-token-auth"
+}
+
+func (a *TokenAuth) String() string {
+	masked := "*******"
+	if a.Token == "" {
+		masked = "<empty>"
+	}
+	return fmt.Sprintf("%s - %s", a.Name(), masked)
+}
+
 // Err is a dedicated error to return errors based on status code
 type Err struct {
 	Response *http.Response

Diff for: plumbing/transport/http/common_test.go

@@ -54,6 +54,19 @@ func (s *ClientSuite) TestNewBasicAuth(c *C) {
 	c.Assert(a.String(), Equals, "http-basic-auth - foo:*******")
 }
 
+func (s *ClientSuite) TestNewTokenAuth(c *C) {
+	a := &TokenAuth{"OAUTH-TOKEN-TEXT"}
+
+	c.Assert(a.Name(), Equals, "http-token-auth")
+	c.Assert(a.String(), Equals, "http-token-auth - *******")
+
+	// Check header is set correctly
+	req, err := http.NewRequest("GET", "https://github.com/git-fixtures/basic", nil)
+	c.Assert(err, Equals, nil)
+	a.setAuth(req)
+	c.Assert(req.Header.Get("Authorization"), Equals, "Bearer OAUTH-TOKEN-TEXT")
+}
+
 func (s *ClientSuite) TestNewErrOK(c *C) {
 	res := &http.Response{StatusCode: http.StatusOK}
 	err := NewErr(res)