chore: replace wsconncache with a single tailnet (#8176)

coderd/coderd.go

@@ -364,8 +364,23 @@ func New(options *Options) *API {
 	}
 
 	api.Auditor.Store(&options.Auditor)
-	api.workspaceAgentCache = wsconncache.New(api.dialWorkspaceAgentTailnet, 0)
 	api.TailnetCoordinator.Store(&options.TailnetCoordinator)
+	if api.Experiments.Enabled(codersdk.ExperimentSingleTailnet) {
+		api.agentProvider, err = NewServerTailnet(api.ctx,
+			options.Logger,
+			options.DERPServer,
+			options.DERPMap,
+			&api.TailnetCoordinator,
+			wsconncache.New(api._dialWorkspaceAgentTailnet, 0),
+		)
+		if err != nil {
+			panic("failed to setup server tailnet: " + err.Error())
+		}
+	} else {
+		api.agentProvider = &wsconncache.AgentProvider{
+			Cache: wsconncache.New(api._dialWorkspaceAgentTailnet, 0),
+		}
+	}
 
 	api.workspaceAppServer = &workspaceapps.Server{
 		Logger: options.Logger.Named("workspaceapps"),
@@ -377,7 +392,7 @@ func New(options *Options) *API {
 		RealIPConfig:  options.RealIPConfig,
 
 		SignedTokenProvider: api.WorkspaceAppsProvider,
-		WorkspaceConnCache:  api.workspaceAgentCache,
+		AgentProvider:       api.agentProvider,
 		AppSecurityKey:      options.AppSecurityKey,
 
 		DisablePathApps:  options.DeploymentValues.DisablePathApps.Value(),
@@ -921,10 +936,10 @@ type API struct {
 	derpCloseFunc      func()
 
 	metricsCache          *metricscache.Cache
-	workspaceAgentCache   *wsconncache.Cache
 	updateChecker         *updatecheck.Checker
 	WorkspaceAppsProvider workspaceapps.SignedTokenProvider
 	workspaceAppServer    *workspaceapps.Server
+	agentProvider         workspaceapps.AgentProvider
 
 	// Experiments contains the list of experiments currently enabled.
 	// This is used to gate features that are not yet ready for production.
@@ -951,7 +966,8 @@ func (api *API) Close() error {
 	if coordinator != nil {
 		_ = (*coordinator).Close()
 	}
-	return api.workspaceAgentCache.Close()
+	_ = api.agentProvider.Close()
+	return nil
 }
 
 func compressHandler(h http.Handler) http.Handler {