MM-19867: - Implement allowing multiple SAML Libraries (#13299)

* Implement allowing multiple SAML Libraries

* fix unit tests

* updates based on review feedback

* Only set on startup, not config changes

* update unit tests, reload enterprise

* need to reset for previous tests

* update license statement

* fix licensing line

app/enterprise.go

@@ -107,6 +107,12 @@ func RegisterSamlInterface(f func(*App) einterfaces.SamlInterface) {
 	samlInterface = f
 }
 
+var samlInterfaceNew func(*App) einterfaces.SamlInterface
+
+func RegisterNewSamlInterface(f func(*App) einterfaces.SamlInterface) {
+	samlInterfaceNew = f
+}
+
 var notificationInterface func(*App) einterfaces.NotificationInterface
 
 func RegisterNotificationInterface(f func(*App) einterfaces.NotificationInterface) {
@@ -136,7 +142,13 @@ func (s *Server) initEnterprise() {
 		s.Notification = notificationInterface(s.FakeApp())
 	}
 	if samlInterface != nil {
-		s.Saml = samlInterface(s.FakeApp())
+		if *s.FakeApp().Config().ExperimentalSettings.UseNewSAMLLibrary && samlInterfaceNew != nil {
+			mlog.Debug("Loading new SAML2 library")
+			s.Saml = samlInterfaceNew(s.FakeApp())
+		} else {
+			mlog.Debug("Loading original SAML library")
+			s.Saml = samlInterface(s.FakeApp())
+		}
 		s.AddConfigListener(func(_, cfg *model.Config) {
 			if err := s.Saml.ConfigureSP(); err != nil {
 				mlog.Error("An error occurred while configuring SAML Service Provider", mlog.Err(err))

app/enterprise_test.go

@@ -0,0 +1,116 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package app
+
+import (
+	"testing"
+
+	"github.com/mattermost/mattermost-server/v5/einterfaces"
+	"github.com/mattermost/mattermost-server/v5/einterfaces/mocks"
+	"github.com/mattermost/mattermost-server/v5/model"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSAMLSettings(t *testing.T) {
+	tt := []struct {
+		name              string
+		setSAMLInterface  bool
+		setNewInterface   bool
+		useNewSAMLLibrary bool
+		isNil             bool
+		metadata          string
+	}{
+		{
+			name:              "No SAML Interfaces, default setting",
+			setSAMLInterface:  false,
+			setNewInterface:   false,
+			useNewSAMLLibrary: false,
+			isNil:             true,
+		},
+		{
+			name:              "No SAML Interfaces, set config true",
+			setSAMLInterface:  false,
+			setNewInterface:   false,
+			useNewSAMLLibrary: true,
+			isNil:             true,
+		},
+		{
+			name:              "Orignal SAML Interface, default setting",
+			setSAMLInterface:  true,
+			setNewInterface:   false,
+			useNewSAMLLibrary: false,
+			isNil:             false,
+			metadata:          "samlOne",
+		},
+		{
+			name:              "Orignal SAML Interface, config true",
+			setSAMLInterface:  true,
+			setNewInterface:   false,
+			useNewSAMLLibrary: true,
+			isNil:             false,
+			metadata:          "samlOne",
+		},
+		{
+			name:              "Both SAML Interfaces, default setting",
+			setSAMLInterface:  true,
+			setNewInterface:   true,
+			useNewSAMLLibrary: false,
+			isNil:             false,
+			metadata:          "samlOne",
+		},
+		{
+			name:              "Both SAML Interfaces, config true",
+			setSAMLInterface:  true,
+			setNewInterface:   true,
+			useNewSAMLLibrary: true,
+			isNil:             false,
+			metadata:          "samlTwo",
+		},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			saml := &mocks.SamlInterface{}
+			saml.Mock.On("ConfigureSP").Return(nil)
+			saml.Mock.On("GetMetadata").Return("samlOne", nil)
+			if tc.setSAMLInterface {
+				RegisterSamlInterface(func(a *App) einterfaces.SamlInterface {
+					return saml
+				})
+			} else {
+				RegisterSamlInterface(nil)
+			}
+
+			saml2 := &mocks.SamlInterface{}
+			saml2.Mock.On("ConfigureSP").Return(nil)
+			saml2.Mock.On("GetMetadata").Return("samlTwo", nil)
+			if tc.setNewInterface {
+				RegisterNewSamlInterface(func(a *App) einterfaces.SamlInterface {
+					return saml2
+				})
+			} else {
+				RegisterNewSamlInterface(nil)
+			}
+
+			th := SetupEnterprise(t).InitBasic()
+			defer th.TearDown()
+
+			if tc.useNewSAMLLibrary {
+				th.App.UpdateConfig(func(cfg *model.Config) {
+					*cfg.ExperimentalSettings.UseNewSAMLLibrary = tc.useNewSAMLLibrary
+				})
+			}
+
+			th.Server.initEnterprise()
+			if tc.isNil {
+				assert.Nil(t, th.App.Srv.Saml)
+			} else {
+				assert.NotNil(t, th.App.Srv.Saml)
+				metadata, err := th.App.Srv.Saml.GetMetadata()
+				assert.Nil(t, err)
+				assert.Equal(t, tc.metadata, metadata)
+			}
+		})
+	}
+}

model/config.go

@@ -797,6 +797,7 @@ type ExperimentalSettings struct {
 	EnableClickToReply              *bool  `restricted:"true"`
 	LinkMetadataTimeoutMilliseconds *int64 `restricted:"true"`
 	RestrictSystemAdmin             *bool  `restricted:"true"`
+	UseNewSAMLLibrary               *bool
 }
 
 func (s *ExperimentalSettings) SetDefaults() {
@@ -819,6 +820,9 @@ func (s *ExperimentalSettings) SetDefaults() {
 	if s.RestrictSystemAdmin == nil {
 		s.RestrictSystemAdmin = NewBool(false)
 	}
+	if s.UseNewSAMLLibrary == nil {
+		s.UseNewSAMLLibrary = NewBool(false)
+	}
 }
 
 type AnalyticsSettings struct {