MM-28859 Add feature flag managment system using split.io and remove viper. (#15954)

* Add feature flag managment system using split.io and remove viper.

* Fixing tests.

* Attempt to fix postgres tests.

* Fix watch filepath for advanced logging.

* Review fixes.

* Some error wrapping.

* Remove unessisary store interface.

* Desanitize SplitKey

* Simplify.

* Review feedback.

* Rename split mlog adatper to split logger.

* fsInner

* Style.

* Restore oldcfg test.

* Downgrading non-actionable feature flag errors to warnings.

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

api4/apitestlib.go

@@ -38,7 +38,7 @@ import (
 type TestHelper struct {
 	App         *app.App
 	Server      *app.Server
-	ConfigStore config.Store
+	ConfigStore *config.Store
 
 	Client               *model.Client4
 	BasicUser            *model.User
@@ -79,20 +79,26 @@ func setupTestHelper(dbStore store.Store, searchEngine *searchengine.Broker, ent
 		panic("failed to initialize memory store: " + err.Error())
 	}
 
-	config := memoryStore.Get()
-	*config.PluginSettings.Directory = filepath.Join(tempWorkspace, "plugins")
-	*config.PluginSettings.ClientDirectory = filepath.Join(tempWorkspace, "webapp")
-	config.ServiceSettings.EnableLocalMode = model.NewBool(true)
-	*config.ServiceSettings.LocalModeSocketLocation = filepath.Join(tempWorkspace, "mattermost_local.sock")
-	*config.AnnouncementSettings.AdminNoticesEnabled = false
-	*config.AnnouncementSettings.UserNoticesEnabled = false
+	memoryConfig := &model.Config{}
+	memoryConfig.SetDefaults()
+	*memoryConfig.PluginSettings.Directory = filepath.Join(tempWorkspace, "plugins")
+	*memoryConfig.PluginSettings.ClientDirectory = filepath.Join(tempWorkspace, "webapp")
+	memoryConfig.ServiceSettings.EnableLocalMode = model.NewBool(true)
+	*memoryConfig.ServiceSettings.LocalModeSocketLocation = filepath.Join(tempWorkspace, "mattermost_local.sock")
+	*memoryConfig.AnnouncementSettings.AdminNoticesEnabled = false
+	*memoryConfig.AnnouncementSettings.UserNoticesEnabled = false
 	if updateConfig != nil {
-		updateConfig(config)
+		updateConfig(memoryConfig)
+	}
+	memoryStore.Set(memoryConfig)
+
+	configStore, err := config.NewStoreFromBacking(memoryStore)
+	if err != nil {
+		panic(err)
 	}
-	memoryStore.Set(config)
 
 	var options []app.Option
-	options = append(options, app.ConfigStore(memoryStore))
+	options = append(options, app.ConfigStore(configStore))
 	options = append(options, app.StoreOverride(dbStore))
 
 	s, err := app.NewServer(options...)
@@ -107,7 +113,7 @@ func setupTestHelper(dbStore store.Store, searchEngine *searchengine.Broker, ent
 	th := &TestHelper{
 		App:               app.New(app.ServerConnector(s)),
 		Server:            s,
-		ConfigStore:       memoryStore,
+		ConfigStore:       configStore,
 		IncludeCacheLayer: includeCache,
 	}
 
@@ -168,7 +174,7 @@ func setupTestHelper(dbStore store.Store, searchEngine *searchengine.Broker, ent
 	th.Client.SetBoolString(true, trueString)
 	th.Client.SetBoolString(false, falseString)
 
-	th.LocalClient = th.CreateLocalClient(*config.ServiceSettings.LocalModeSocketLocation)
+	th.LocalClient = th.CreateLocalClient(*memoryConfig.ServiceSettings.LocalModeSocketLocation)
 
 	if th.tempWorkspace == "" {
 		th.tempWorkspace = tempWorkspace

api4/system_test.go

@@ -14,7 +14,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/mattermost/mattermost-server/v5/config"
 	"github.com/mattermost/mattermost-server/v5/mlog"
 	"github.com/mattermost/mattermost-server/v5/model"
 	"github.com/stretchr/testify/assert"
@@ -68,6 +67,7 @@ func TestGetPing(t *testing.T) {
 	}, "with server status")
 
 	th.TestForAllClients(t, func(t *testing.T, client *model.Client4) {
+		th.App.ReloadConfig()
 		resp, appErr := client.DoApiGet(client.GetSystemRoute()+"/ping", "")
 		require.Nil(t, appErr)
 		require.Equal(t, http.StatusOK, resp.StatusCode)
@@ -77,15 +77,9 @@ func TestGetPing(t *testing.T) {
 		require.NotContains(t, respString, "TestFeatureFlag")
 
 		// Run the enviroment variable override code to test
-		os.Setenv("MM_FEATUREFLAGS_TESTFEATURE", "testvalue")
+		os.Setenv("MM_FEATUREFLAGS_TESTFEATURE", "testvalueunique")
 		defer os.Unsetenv("MM_FEATUREFLAGS_TESTFEATURE")
-		memoryStore, err := config.NewMemoryStore()
-		require.Nil(t, err)
-		retrievedConfig := memoryStore.Get()
-
-		// replace config with generated config
-		oldConfig := th.App.Config().Clone()
-		th.App.UpdateConfig(func(cfg *model.Config) { *cfg = *retrievedConfig })
+		th.App.ReloadConfig()
 
 		resp, appErr = client.DoApiGet(client.GetSystemRoute()+"/ping", "")
 		require.Nil(t, appErr)
@@ -94,7 +88,6 @@ func TestGetPing(t *testing.T) {
 		require.Nil(t, err)
 		respString = string(respBytes)
 		require.Contains(t, respString, "testvalue")
-		th.App.UpdateConfig(func(cfg *model.Config) { *cfg = *oldConfig })
 	}, "ping feature flag test")
 }