[MM-60648] Don't start server until all routes are registered (#28291)

server/channels/api4/api.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/mattermost/mattermost/server/public/model"
 	"github.com/mattermost/mattermost/server/v8/channels/app"
+	"github.com/mattermost/mattermost/server/v8/channels/manualtesting"
 	"github.com/mattermost/mattermost/server/v8/channels/web"
 )
 
@@ -337,6 +338,11 @@ func Init(srv *app.Server) (*API, error) {
 	api.InitOutgoingOAuthConnection()
 	api.InitClientPerformanceMetrics()
 
+	// If we allow testing then listen for manual testing URL hits
+	if *srv.Config().ServiceSettings.EnableTesting {
+		api.BaseRoutes.Root.Handle("/manualtest", api.APIHandler(manualtesting.ManualTest)).Methods(http.MethodGet)
+	}
+
 	srv.Router.Handle("/api/v4/{anything:.*}", http.HandlerFunc(api.Handle404))
 
 	InitLocal(srv)

server/channels/manualtesting/manual_testing.go

@@ -15,7 +15,6 @@ import (
 
 	"github.com/mattermost/mattermost/server/public/model"
 	"github.com/mattermost/mattermost/server/public/shared/mlog"
-	"github.com/mattermost/mattermost/server/v8/channels/api4"
 	"github.com/mattermost/mattermost/server/v8/channels/app"
 	"github.com/mattermost/mattermost/server/v8/channels/app/slashcommands"
 	"github.com/mattermost/mattermost/server/v8/channels/store"
@@ -34,12 +33,7 @@ type TestEnvironment struct {
 	Request       *http.Request
 }
 
-// Init adds manualtest endpoint to the API.
-func Init(api4 *api4.API) {
-	api4.BaseRoutes.Root.Handle("/manualtest", api4.APIHandler(manualTest)).Methods(http.MethodGet)
-}
-
-func manualTest(c *web.Context, w http.ResponseWriter, r *http.Request) {
+func ManualTest(c *web.Context, w http.ResponseWriter, r *http.Request) {
 	// Let the world know
 	c.Logger.Info("Setting up for manual test...")