From c3c81cb3d6a29ef8164a8e7ef4ba172d60117176 Mon Sep 17 00:00:00 2001
From: Michael Kochell <6913320+mickmister@users.noreply.github.com>
Date: Tue, 6 Dec 2022 12:44:48 -0500
Subject: [PATCH] MM-48120/MM-48623 Patch plugin bundle react-dom on webapp
 extract (#21171)

Automatic Merge
---
 app/plugin.go                        | 10 +++-
 app/plugin_api_test.go               | 12 ++---
 app/plugin_hooks_test.go             |  4 +-
 model/config.go                      |  5 ++
 plugin/environment.go                | 71 ++++++++++++++++++++++++++--
 services/telemetry/telemetry.go      |  1 +
 services/telemetry/telemetry_test.go |  1 +
 web/web_test.go                      |  2 +-
 8 files changed, 93 insertions(+), 13 deletions(-)

diff --git a/app/plugin.go b/app/plugin.go
index 93d47fd5b6..7ce6c47fe6 100644
--- a/app/plugin.go
+++ b/app/plugin.go
@@ -243,7 +243,15 @@ func (ch *Channels) initPlugins(c *request.Context, pluginDir, webappPluginDir s
 		return New(ServerConnector(ch)).NewPluginAPI(c, manifest)
 	}
 
-	env, err := plugin.NewEnvironment(newAPIFunc, NewDriverImpl(ch.srv), pluginDir, webappPluginDir, ch.srv.Log(), ch.srv.GetMetrics())
+	env, err := plugin.NewEnvironment(
+		newAPIFunc,
+		NewDriverImpl(ch.srv),
+		pluginDir,
+		webappPluginDir,
+		*ch.cfgSvc.Config().ExperimentalSettings.PatchPluginsReactDOM,
+		ch.srv.Log(),
+		ch.srv.GetMetrics(),
+	)
 	if err != nil {
 		mlog.Error("Failed to start up plugins", mlog.Err(err))
 		return
diff --git a/app/plugin_api_test.go b/app/plugin_api_test.go
index 9f864109bf..759613781b 100644
--- a/app/plugin_api_test.go
+++ b/app/plugin_api_test.go
@@ -92,7 +92,7 @@ func setupMultiPluginAPITest(t *testing.T, pluginCodes []string, pluginManifests
 		return app.NewPluginAPI(c, manifest)
 	}
 
-	env, err := plugin.NewEnvironment(newPluginAPI, NewDriverImpl(app.Srv()), pluginDir, webappPluginDir, app.Log(), nil)
+	env, err := plugin.NewEnvironment(newPluginAPI, NewDriverImpl(app.Srv()), pluginDir, webappPluginDir, false, app.Log(), nil)
 	require.NoError(t, err)
 
 	require.Equal(t, len(pluginCodes), len(pluginIDs))
@@ -849,7 +849,7 @@ func TestPluginAPIGetPlugins(t *testing.T) {
 	defer os.RemoveAll(pluginDir)
 	defer os.RemoveAll(webappPluginDir)
 
-	env, err := plugin.NewEnvironment(th.NewPluginAPI, NewDriverImpl(th.Server), pluginDir, webappPluginDir, th.App.Log(), nil)
+	env, err := plugin.NewEnvironment(th.NewPluginAPI, NewDriverImpl(th.Server), pluginDir, webappPluginDir, false, th.App.Log(), nil)
 	require.NoError(t, err)
 
 	pluginIDs := []string{"pluginid1", "pluginid2", "pluginid3"}
@@ -937,7 +937,7 @@ func TestInstallPlugin(t *testing.T) {
 			return app.NewPluginAPI(c, manifest)
 		}
 
-		env, err := plugin.NewEnvironment(newPluginAPI, NewDriverImpl(app.Srv()), pluginDir, webappPluginDir, app.Log(), nil)
+		env, err := plugin.NewEnvironment(newPluginAPI, NewDriverImpl(app.Srv()), pluginDir, webappPluginDir, false, app.Log(), nil)
 		require.NoError(t, err)
 
 		app.ch.SetPluginsEnvironment(env)
@@ -1632,7 +1632,7 @@ func TestAPIMetrics(t *testing.T) {
 		defer os.RemoveAll(pluginDir)
 		defer os.RemoveAll(webappPluginDir)
 
-		env, err := plugin.NewEnvironment(th.NewPluginAPI, NewDriverImpl(th.Server), pluginDir, webappPluginDir, th.App.Log(), metricsMock)
+		env, err := plugin.NewEnvironment(th.NewPluginAPI, NewDriverImpl(th.Server), pluginDir, webappPluginDir, false, th.App.Log(), metricsMock)
 		require.NoError(t, err)
 
 		th.App.ch.SetPluginsEnvironment(env)
@@ -2079,7 +2079,7 @@ func TestRegisterCollectionAndTopic(t *testing.T) {
 		return th.App.NewPluginAPI(th.Context, manifest)
 	}
 
-	env, err := plugin.NewEnvironment(newPluginAPI, NewDriverImpl(th.App.Srv()), pluginDir, webappPluginDir, th.App.Log(), nil)
+	env, err := plugin.NewEnvironment(newPluginAPI, NewDriverImpl(th.App.Srv()), pluginDir, webappPluginDir, false, th.App.Log(), nil)
 	require.NoError(t, err)
 
 	th.App.ch.SetPluginsEnvironment(env)
@@ -2179,7 +2179,7 @@ func TestPluginUploadsAPI(t *testing.T) {
 	newPluginAPI := func(manifest *model.Manifest) plugin.API {
 		return th.App.NewPluginAPI(th.Context, manifest)
 	}
-	env, err := plugin.NewEnvironment(newPluginAPI, NewDriverImpl(th.App.Srv()), pluginDir, webappPluginDir, th.App.Log(), nil)
+	env, err := plugin.NewEnvironment(newPluginAPI, NewDriverImpl(th.App.Srv()), pluginDir, webappPluginDir, false, th.App.Log(), nil)
 	require.NoError(t, err)
 
 	th.App.ch.SetPluginsEnvironment(env)
diff --git a/app/plugin_hooks_test.go b/app/plugin_hooks_test.go
index 7cd81f8fae..161994a1ab 100644
--- a/app/plugin_hooks_test.go
+++ b/app/plugin_hooks_test.go
@@ -33,7 +33,7 @@ func SetAppEnvironmentWithPlugins(t *testing.T, pluginCode []string, app *App, a
 	webappPluginDir, err := os.MkdirTemp("", "")
 	require.NoError(t, err)
 
-	env, err := plugin.NewEnvironment(apiFunc, NewDriverImpl(app.Srv()), pluginDir, webappPluginDir, app.Log(), nil)
+	env, err := plugin.NewEnvironment(apiFunc, NewDriverImpl(app.Srv()), pluginDir, webappPluginDir, false, app.Log(), nil)
 	require.NoError(t, err)
 
 	app.ch.SetPluginsEnvironment(env)
@@ -1030,7 +1030,7 @@ func TestHookMetrics(t *testing.T) {
 		defer os.RemoveAll(pluginDir)
 		defer os.RemoveAll(webappPluginDir)
 
-		env, err := plugin.NewEnvironment(th.NewPluginAPI, NewDriverImpl(th.Server), pluginDir, webappPluginDir, th.App.Log(), metricsMock)
+		env, err := plugin.NewEnvironment(th.NewPluginAPI, NewDriverImpl(th.Server), pluginDir, webappPluginDir, false, th.App.Log(), metricsMock)
 		require.NoError(t, err)
 
 		th.App.ch.SetPluginsEnvironment(env)
diff --git a/model/config.go b/model/config.go
index 058a7b7666..dd0ad5cfd3 100644
--- a/model/config.go
+++ b/model/config.go
@@ -968,6 +968,7 @@ type ExperimentalSettings struct {
 	EnableSharedChannels            *bool   `access:"experimental_features"`
 	EnableRemoteClusterService      *bool   `access:"experimental_features"`
 	EnableAppBar                    *bool   `access:"experimental_features"`
+	PatchPluginsReactDOM            *bool   `access:"experimental_features"`
 }
 
 func (s *ExperimentalSettings) SetDefaults() {
@@ -1002,6 +1003,10 @@ func (s *ExperimentalSettings) SetDefaults() {
 	if s.EnableAppBar == nil {
 		s.EnableAppBar = NewBool(false)
 	}
+
+	if s.PatchPluginsReactDOM == nil {
+		s.PatchPluginsReactDOM = NewBool(false)
+	}
 }
 
 type AnalyticsSettings struct {
diff --git a/plugin/environment.go b/plugin/environment.go
index db07f051bd..4ccbbdf023 100644
--- a/plugin/environment.go
+++ b/plugin/environment.go
@@ -4,10 +4,12 @@
 package plugin
 
 import (
+	"bytes"
 	"fmt"
 	"hash/fnv"
 	"os"
 	"path/filepath"
+	"strings"
 	"sync"
 	"time"
 
@@ -57,15 +59,20 @@ type Environment struct {
 	dbDriver               Driver
 	pluginDir              string
 	webappPluginDir        string
+	patchReactDOM          bool
 	prepackagedPlugins     []*PrepackagedPlugin
 	prepackagedPluginsLock sync.RWMutex
 }
 
-func NewEnvironment(newAPIImpl apiImplCreatorFunc,
+func NewEnvironment(
+	newAPIImpl apiImplCreatorFunc,
 	dbDriver Driver,
-	pluginDir string, webappPluginDir string,
+	pluginDir string,
+	webappPluginDir string,
+	patchReactDOM bool,
 	logger *mlog.Logger,
-	metrics einterfaces.MetricsInterface) (*Environment, error) {
+	metrics einterfaces.MetricsInterface,
+) (*Environment, error) {
 	return &Environment{
 		logger:          logger,
 		metrics:         metrics,
@@ -73,6 +80,7 @@ func NewEnvironment(newAPIImpl apiImplCreatorFunc,
 		dbDriver:        dbDriver,
 		pluginDir:       pluginDir,
 		webappPluginDir: webappPluginDir,
+		patchReactDOM:   patchReactDOM,
 	}, nil
 }
 
@@ -451,6 +459,17 @@ func (env *Environment) UnpackWebappBundle(id string) (*model.Manifest, error) {
 		return nil, errors.Wrapf(err, "unable to read webapp bundle: %v", id)
 	}
 
+	if env.patchReactDOM {
+		newContents, changed := patchReactDOM(sourceBundleFileContents)
+		if changed {
+			sourceBundleFileContents = newContents
+			err = os.WriteFile(sourceBundleFilepath, sourceBundleFileContents, 0644)
+			if err != nil {
+				return nil, errors.Wrapf(err, "unable to overwrite webapp bundle: %v", id)
+			}
+		}
+	}
+
 	hash := fnv.New64a()
 	if _, err = hash.Write(sourceBundleFileContents); err != nil {
 		return nil, errors.Wrapf(err, "unable to generate hash for webapp bundle: %v", id)
@@ -467,6 +486,52 @@ func (env *Environment) UnpackWebappBundle(id string) (*model.Manifest, error) {
 	return manifest, nil
 }
 
+func patchReactDOM(initialBytes []byte) ([]byte, bool) {
+	if !bytes.Contains(initialBytes, []byte("react-dom.production.min.js")) {
+		return initialBytes, false
+	}
+
+	initial := string(initialBytes)
+	nameIndex := strings.Index(initial, "react-dom.production.min.js")
+
+	beginning := strings.LastIndex(initial[:nameIndex], "{")
+	var end int
+
+	argDefBeginning := strings.LastIndex(initial[:beginning], "function") + 9
+	argDefEnd := strings.LastIndex(initial[:beginning], ")") - 1
+	argsNames := strings.Split(initial[argDefBeginning:argDefEnd], ",")
+	if len(argsNames) != 3 {
+		return initialBytes, false
+	}
+
+	exportsArgName := strings.TrimSpace(argsNames[1])
+
+	numOpenBraces := 0
+	for i, c := range initial[beginning:] {
+		if end != 0 {
+			break
+		}
+		switch c {
+		case '}':
+			numOpenBraces--
+
+			if numOpenBraces == 0 {
+				end = beginning + i
+			}
+		case '{':
+			numOpenBraces++
+		}
+	}
+
+	beforePatch := initial[:end]
+	afterPatch := initial[end:]
+
+	patch := fmt.Sprintf("; Object.assign(%s, window.ReactDOM)", exportsArgName)
+
+	result := fmt.Sprintf("%s%s%s", beforePatch, patch, afterPatch)
+	return []byte(result), true
+}
+
 // HooksForPlugin returns the hooks API for the plugin with the given id.
 //
 // Consider using RunMultiPluginHook instead.
diff --git a/services/telemetry/telemetry.go b/services/telemetry/telemetry.go
index ee8fea6f11..ce9eb79419 100644
--- a/services/telemetry/telemetry.go
+++ b/services/telemetry/telemetry.go
@@ -734,6 +734,7 @@ func (ts *TelemetryService) trackConfig() {
 		"enable_shared_channels":             *cfg.ExperimentalSettings.EnableSharedChannels,
 		"enable_remote_cluster_service":      *cfg.ExperimentalSettings.EnableRemoteClusterService && cfg.FeatureFlags.EnableRemoteClusterService,
 		"enable_app_bar":                     *cfg.ExperimentalSettings.EnableAppBar,
+		"patch_plugins_react_dom":            *cfg.ExperimentalSettings.PatchPluginsReactDOM,
 	})
 
 	ts.SendTelemetry(TrackConfigAnalytics, map[string]any{
diff --git a/services/telemetry/telemetry_test.go b/services/telemetry/telemetry_test.go
index 31ab7656ad..32a86602a3 100644
--- a/services/telemetry/telemetry_test.go
+++ b/services/telemetry/telemetry_test.go
@@ -165,6 +165,7 @@ func initializeMocks(cfg *model.Config, cloudLicense bool) (*mocks.ServerIface,
 		func(m *model.Manifest) plugin.API { return pluginsAPIMock },
 		nil,
 		pluginDir, webappPluginDir,
+		false,
 		logger,
 		nil)
 	serverIfaceMock.On("GetPluginsEnvironment").Return(pluginEnv, nil)
diff --git a/web/web_test.go b/web/web_test.go
index 139753675d..ae8e322f91 100644
--- a/web/web_test.go
+++ b/web/web_test.go
@@ -280,7 +280,7 @@ func TestPublicFilesRequest(t *testing.T) {
 	defer os.RemoveAll(pluginDir)
 	defer os.RemoveAll(webappPluginDir)
 
-	env, err := plugin.NewEnvironment(th.NewPluginAPI, app.NewDriverImpl(th.Server), pluginDir, webappPluginDir, th.App.Log(), nil)
+	env, err := plugin.NewEnvironment(th.NewPluginAPI, app.NewDriverImpl(th.Server), pluginDir, webappPluginDir, false, th.App.Log(), nil)
 	require.NoError(t, err)
 
 	pluginID := "com.mattermost.sample"