Add set basic auth param (#413)

* addint redirect capability to sign_out

* updating changelog

* Add a new param to set the Authorization header to up-stream systems as Basic user:password

* Resolving code review

* mutual exclusiv changes for Basic and Bearer Authorization header

* Fixed the merge mixup and comment error

* Updated changelog and fixed typo

* Adding the new entry in changelog

Co-authored-by: Costel Moraru <costel.moraru-germany@ibm.com>

oauthproxy_test.go

@@ -404,6 +404,7 @@ func TestBasicAuthPassword(t *testing.T) {
 	opts.ClientSecret = "alkgret"
 	opts.CookieSecure = false
 	opts.PassBasicAuth = true
+	opts.SetBasicAuth = true
 	opts.PassUserHeaders = true
 	opts.PreferEmailToUser = true
 	opts.BasicAuthPassword = "This is a secure password"
@@ -1075,6 +1076,71 @@ func TestAuthOnlyEndpointSetXAuthRequestHeaders(t *testing.T) {
 	assert.Equal(t, "oauth_user@example.com", pcTest.rw.HeaderMap["X-Auth-Request-Email"][0])
 }
 
+func TestAuthOnlyEndpointSetBasicAuthTrueRequestHeaders(t *testing.T) {
+	var pcTest ProcessCookieTest
+
+	pcTest.opts = NewOptions()
+	pcTest.opts.SetXAuthRequest = true
+	pcTest.opts.SetBasicAuth = true
+	pcTest.opts.Validate()
+
+	pcTest.proxy = NewOAuthProxy(pcTest.opts, func(email string) bool {
+		return pcTest.validateUser
+	})
+	pcTest.proxy.provider = &TestProvider{
+		ValidToken: true,
+	}
+
+	pcTest.validateUser = true
+
+	pcTest.rw = httptest.NewRecorder()
+	pcTest.req, _ = http.NewRequest("GET",
+		pcTest.opts.ProxyPrefix+"/auth", nil)
+
+	startSession := &sessions.SessionState{
+		User: "oauth_user", Email: "oauth_user@example.com", AccessToken: "oauth_token", CreatedAt: time.Now()}
+	pcTest.SaveSession(startSession)
+
+	pcTest.proxy.ServeHTTP(pcTest.rw, pcTest.req)
+	assert.Equal(t, http.StatusAccepted, pcTest.rw.Code)
+	assert.Equal(t, "oauth_user", pcTest.rw.HeaderMap["X-Auth-Request-User"][0])
+	assert.Equal(t, "oauth_user@example.com", pcTest.rw.HeaderMap["X-Auth-Request-Email"][0])
+	expectedHeader := "Basic " + base64.StdEncoding.EncodeToString([]byte("oauth_user:"+pcTest.opts.BasicAuthPassword))
+	assert.Equal(t, expectedHeader, pcTest.rw.HeaderMap["Authorization"][0])
+}
+
+func TestAuthOnlyEndpointSetBasicAuthFalseRequestHeaders(t *testing.T) {
+	var pcTest ProcessCookieTest
+
+	pcTest.opts = NewOptions()
+	pcTest.opts.SetXAuthRequest = true
+	pcTest.opts.SetBasicAuth = false
+	pcTest.opts.Validate()
+
+	pcTest.proxy = NewOAuthProxy(pcTest.opts, func(email string) bool {
+		return pcTest.validateUser
+	})
+	pcTest.proxy.provider = &TestProvider{
+		ValidToken: true,
+	}
+
+	pcTest.validateUser = true
+
+	pcTest.rw = httptest.NewRecorder()
+	pcTest.req, _ = http.NewRequest("GET",
+		pcTest.opts.ProxyPrefix+"/auth", nil)
+
+	startSession := &sessions.SessionState{
+		User: "oauth_user", Email: "oauth_user@example.com", AccessToken: "oauth_token", CreatedAt: time.Now()}
+	pcTest.SaveSession(startSession)
+
+	pcTest.proxy.ServeHTTP(pcTest.rw, pcTest.req)
+	assert.Equal(t, http.StatusAccepted, pcTest.rw.Code)
+	assert.Equal(t, "oauth_user", pcTest.rw.HeaderMap["X-Auth-Request-User"][0])
+	assert.Equal(t, "oauth_user@example.com", pcTest.rw.HeaderMap["X-Auth-Request-Email"][0])
+	assert.Equal(t, 0, len(pcTest.rw.HeaderMap["Authorization"]), "should not have Authorization header entries")
+}
+
 func TestAuthSkippedForPreflightRequests(t *testing.T) {
 	upstream := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(200)