feat(auth): Bearer Auth Support (oauth 2.0)

jira.go

@@ -382,6 +382,41 @@ func (t *BasicAuthTransport) transport() http.RoundTripper {
 	return http.DefaultTransport
 }
 
+// BearerAuthTransport is a http.RoundTripper that authenticates all requests
+// using Jira's bearer (oauth 2.0 (3lo)) based authentication.
+type BearerAuthTransport struct {
+	Token string
+
+	// Transport is the underlying HTTP transport to use when making requests.
+	// It will default to http.DefaultTransport if nil.
+	Transport http.RoundTripper
+}
+
+// RoundTrip implements the RoundTripper interface.  We just add the
+// bearer token and return the RoundTripper for this transport type.
+func (t *BearerAuthTransport) RoundTrip(req *http.Request) (*http.Response, error) {
+	req2 := cloneRequest(req) // per RoundTripper contract
+
+	req2.Header.Set("Authorization", fmt.Sprintf("Bearer %s", t.Token))
+	return t.transport().RoundTrip(req2)
+}
+
+// Client returns an *http.Client that makes requests that are authenticated
+// using HTTP Basic Authentication.  This is a nice little bit of sugar
+// so we can just get the client instead of creating the client in the calling code.
+// If it's necessary to send more information on client init, the calling code can
+// always skip this and set the transport itself.
+func (t *BearerAuthTransport) Client() *http.Client {
+	return &http.Client{Transport: t}
+}
+
+func (t *BearerAuthTransport) transport() http.RoundTripper {
+	if t.Transport != nil {
+		return t.Transport
+	}
+	return http.DefaultTransport
+}
+
 // PATAuthTransport is an http.RoundTripper that authenticates all requests
 // using the Personal Access Token specified.
 // See here for more info: https://confluence.atlassian.com/enterprise/using-personal-access-tokens-1026032365.html