add config reloading via API endpoint and more WS work

api.go

@@ -1,46 +1,145 @@
 package showbridge
 
 import (
+	"context"
 	"embed"
 	_ "embed"
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"time"
+
+	"github.com/jwetzell/showbridge-go/internal/config"
+	"github.com/jwetzell/showbridge-go/internal/module"
+	"github.com/jwetzell/showbridge-go/internal/route"
 )
 
+func (r *Router) startAPIServer(config config.ApiConfig) {
+	r.logger.Debug("starting API server", "port", config.Port)
+	mux := http.NewServeMux()
+	mux.HandleFunc("/ws", r.handleWebsocket)
+	mux.HandleFunc("/health", r.handleHealthHTTP)
+	mux.HandleFunc("/schema/{schema}", r.handleSchemaHTTP)
+	mux.HandleFunc("/api/v1/config", r.handleConfigHTTP)
+
+	r.apiServerMu.Lock()
+	defer r.apiServerMu.Unlock()
+	r.apiServer = &http.Server{
+		Addr:    fmt.Sprintf(":%d", config.Port),
+		Handler: mux,
+	}
+
+	go func() {
+		r.apiServer.ListenAndServe()
+		r.apiServerShutdown()
+	}()
+}
+
+func (r *Router) stopAPIServer() {
+	r.logger.Debug("stopping API server")
+	r.apiServerMu.Lock()
+	defer r.apiServerMu.Unlock()
+	if r.apiServer != nil {
+		apiShutdownCtx, apiShutdownCancel := context.WithTimeout(context.Background(), 5*time.Second)
+		r.apiServerShutdown = apiShutdownCancel
+		r.apiServer.Shutdown(apiShutdownCtx)
+		<-apiShutdownCtx.Done()
+		r.apiServer = nil
+	}
+}
+
+func (r *Router) handleHealthHTTP(w http.ResponseWriter, req *http.Request) {
+	switch req.Method {
+	case http.MethodGet:
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.WriteHeader(http.StatusOK)
+	case http.MethodOptions:
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.Header().Set("Access-Control-Allow-Methods", "GET, OPTIONS")
+		w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+		w.WriteHeader(http.StatusOK)
+	default:
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.WriteHeader(http.StatusMethodNotAllowed)
+	}
+}
+
 func (r *Router) handleConfigHTTP(w http.ResponseWriter, req *http.Request) {
-	if req.Method != http.MethodGet {
-		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
-		return
+
+	switch req.Method {
+	case http.MethodGet:
+		configJSON, err := json.Marshal(r.runningConfig)
+		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.Header().Set("Content-Type", "application/json")
+		w.Write(configJSON)
+	case http.MethodPut:
+		var newConfig config.Config
+		err := json.NewDecoder(req.Body).Decode(&newConfig)
+		if err != nil {
+			http.Error(w, "Bad request", http.StatusBadRequest)
+			return
+		}
+		moduleErrors, routeErrors := r.UpdateConfig(newConfig)
+		if len(moduleErrors) > 0 || len(routeErrors) > 0 {
+			errorResponse := struct {
+				ModuleErrors []module.ModuleError `json:"moduleErrors,omitempty"`
+				RouteErrors  []route.RouteError   `json:"routeErrors,omitempty"`
+			}{
+				ModuleErrors: moduleErrors,
+				RouteErrors:  routeErrors,
+			}
+			errorResponseJSON, err := json.Marshal(errorResponse)
+			if err != nil {
+				http.Error(w, "Internal server error", http.StatusInternalServerError)
+				return
+			}
+			w.Header().Set("Access-Control-Allow-Origin", "*")
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(http.StatusBadRequest)
+			w.Write(errorResponseJSON)
+			return
+		}
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.WriteHeader(http.StatusOK)
+	case http.MethodOptions:
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.Header().Set("Access-Control-Allow-Methods", "GET, PUT, OPTIONS")
+		w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+		w.WriteHeader(http.StatusOK)
+	default:
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.WriteHeader(http.StatusMethodNotAllowed)
 	}
 
-	configJSON, err := json.Marshal(r.runningConfig)
-	if err != nil {
-		http.Error(w, "Internal server error", http.StatusInternalServerError)
-		return
-	}
-
-	w.Header().Set("Access-Control-Allow-Origin", "*")
-	w.Header().Set("Content-Type", "application/json")
-	w.Write(configJSON)
 }
 
 //go:embed schema
 var schema embed.FS
 
 func (r *Router) handleSchemaHTTP(w http.ResponseWriter, req *http.Request) {
-	if req.Method != http.MethodGet {
-		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
-		return
+	switch req.Method {
+	case http.MethodGet:
+		schemaName := req.PathValue("schema")
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.Header().Set("Content-Type", "application/json")
+		configSchema, err := schema.ReadFile(fmt.Sprintf("schema/%s.schema.json", schemaName))
+		if err != nil {
+			http.Error(w, "Internal server error", http.StatusInternalServerError)
+			return
+		}
+		w.Write(configSchema)
+	case http.MethodOptions:
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.Header().Set("Access-Control-Allow-Methods", "GET, OPTIONS")
+		w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+		w.WriteHeader(http.StatusOK)
+	default:
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.WriteHeader(http.StatusMethodNotAllowed)
 	}
-
-	schemaName := req.PathValue("schema")
-	w.Header().Set("Access-Control-Allow-Origin", "*")
-	w.Header().Set("Content-Type", "application/json")
-	configSchema, err := schema.ReadFile(fmt.Sprintf("schema/%s.schema.json", schemaName))
-	if err != nil {
-		http.Error(w, "Internal server error", http.StatusInternalServerError)
-		return
-	}
-	w.Write(configSchema)
 }

cmd/showbridge/main.go

@@ -13,6 +13,8 @@ import (
 
 	"github.com/jwetzell/showbridge-go"
 	"github.com/jwetzell/showbridge-go/internal/config"
+	"github.com/jwetzell/showbridge-go/internal/module"
+	"github.com/jwetzell/showbridge-go/internal/route"
 	"github.com/urfave/cli/v3"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
@@ -173,7 +175,19 @@ func run(ctx context.Context, c *cli.Command) error {
 		routerRunner: &sync.WaitGroup{},
 	}
 
-	router, err := showbridgeApp.getNewRouter()
+	config, err := readConfig(showbridgeApp.configPath)
+	if err != nil {
+		return err
+	}
+
+	router, moduleErrors, routeErrors := showbridge.NewRouter(config)
+
+	showbridgeApp.logConfigErrors(moduleErrors, routeErrors)
+
+	if moduleErrors != nil || routeErrors != nil {
+		return fmt.Errorf("errors initializing modules or routes")
+	}
+
 	if err != nil {
 		return fmt.Errorf("failed to initialize router: %w", err)
 	}
@@ -200,18 +214,15 @@ func (app *showbridgeApp) handleHangup() {
 		select {
 		case <-sigHangup:
 			app.logger.Info("received SIGHUP, reloading configuration")
-			newRouter, err := app.getNewRouter()
+			app.routerMutex.Lock()
+			config, err := readConfig(app.configPath)
 			if err != nil {
-				app.logger.Error("failed to reload configuration", "error", err)
+				app.logger.Error("failed to read config file", "error", err)
+				app.routerMutex.Unlock()
 				continue
 			}
-			app.routerMutex.Lock()
-			app.router.Stop()
-			app.routerRunner.Wait()
-			app.router = newRouter
-			app.routerRunner.Go(func() {
-				app.router.Start(context.Background())
-			})
+			moduleErrors, routeErrors := app.router.UpdateConfig(config)
+			app.logConfigErrors(moduleErrors, routeErrors)
 			app.logger.Info("configuration reloaded successfully")
 			app.routerMutex.Unlock()
 		case <-app.ctx.Done():
@@ -220,15 +231,7 @@ func (app *showbridgeApp) handleHangup() {
 	}
 }
 
-func (app *showbridgeApp) getNewRouter() (*showbridge.Router, error) {
-	// TODO(jwetzell): what should happen when the config file is unchanged?
-	config, err := readConfig(app.configPath)
-	if err != nil {
-		return nil, err
-	}
-
-	router, moduleErrors, routeErrors := showbridge.NewRouter(config)
-
+func (app *showbridgeApp) logConfigErrors(moduleErrors []module.ModuleError, routeErrors []route.RouteError) {
 	for _, moduleError := range moduleErrors {
 		app.logger.Error("problem initializing module", "index", moduleError.Index, "error", moduleError.Error)
 	}
@@ -236,12 +239,6 @@ func (app *showbridgeApp) getNewRouter() (*showbridge.Router, error) {
 	for _, routeError := range routeErrors {
 		app.logger.Error("problem initializing route", "index", routeError.Index, "error", routeError.Error)
 	}
-
-	if moduleErrors != nil || routeErrors != nil {
-		return nil, fmt.Errorf("errors initializing modules or routes")
-	}
-
-	return router, nil
 }
 
 func newTracerProvider(exp sdktrace.SpanExporter) *sdktrace.TracerProvider {

events.go

@@ -16,16 +16,28 @@ func (e Event) toJSON() ([]byte, error) {
 	return json.Marshal(e)
 }
 
-func (r *Router) handleEvent(event Event) {
+func (r *Router) handleEvent(event Event, sender *websocket.Conn) {
 	switch event.Type {
 	case "ping":
-		r.broadcastEvent(Event{Type: "pong"})
+		r.unicastEvent(Event{Type: "pong"}, sender)
 	default:
 		r.logger.Warn("unknown event type", "eventType", event.Type)
 	}
 }
 
-func (r *Router) broadcastEvent(event Event) {
+func (r *Router) unicastEvent(event Event, conn *websocket.Conn) {
+	eventJSON, err := event.toJSON()
+	if err != nil {
+		r.logger.Error("failed to marshal event to JSON", "error", err)
+		return
+	}
+	err = conn.WriteMessage(websocket.TextMessage, eventJSON)
+	if err != nil {
+		r.logger.Error("failed to write message to websocket connection", "error", err)
+	}
+}
+
+func (r *Router) broadcastEvent(event Event, excluded ...*websocket.Conn) {
 	eventJSON, err := event.toJSON()
 	if err != nil {
 		r.logger.Error("failed to marshal event to JSON", "error", err)
@@ -34,6 +46,16 @@ func (r *Router) broadcastEvent(event Event) {
 	r.wsConnsMu.Lock()
 	defer r.wsConnsMu.Unlock()
 	for _, conn := range r.wsConns {
+		exclude := false
+		for _, excludedConn := range excluded {
+			if conn == excludedConn {
+				exclude = true
+				break
+			}
+		}
+		if exclude {
+			continue
+		}
 		err := conn.WriteMessage(websocket.TextMessage, eventJSON)
 		if err != nil {
 			r.logger.Error("failed to write message to websocket connection", "error", err)

router.go

@@ -3,11 +3,10 @@ package showbridge
 import (
 	"context"
 	"errors"
-	"fmt"
 	"log/slog"
 	"net/http"
+	"reflect"
 	"sync"
-	"time"
 
 	"github.com/gorilla/websocket"
 	"github.com/jwetzell/showbridge-go/internal/common"
@@ -22,17 +21,21 @@ import (
 )
 
 type Router struct {
-	contextCancel   context.CancelFunc
-	Context         context.Context
+	contextCancel context.CancelFunc
+	Context       context.Context
+	// TODO(jwetzell): do these need to be guarded against concurrency?
 	ModuleInstances map[string]module.Module
 	// TODO(jwetzell): change to something easier to lookup
-	RouteInstances []*route.Route
-	moduleWait     sync.WaitGroup
-	logger         *slog.Logger
-	runningConfig  config.Config
-	wsConns        []*websocket.Conn
-	wsConnsMu      sync.Mutex
-	apiServer      *http.Server
+	RouteInstances    []*route.Route
+	moduleWait        sync.WaitGroup
+	logger            *slog.Logger
+	runningConfig     config.Config
+	runningConfigMu   sync.Mutex
+	wsConns           []*websocket.Conn
+	wsConnsMu         sync.Mutex
+	apiServer         *http.Server
+	apiServerMu       sync.Mutex
+	apiServerShutdown context.CancelFunc
 }
 
 func (r *Router) addModule(moduleDecl config.ModuleConfig) error {
@@ -162,32 +165,11 @@ func (r *Router) Start(ctx context.Context) {
 	routerContext, cancel := context.WithCancel(ctx)
 	r.Context = routerContext
 	r.contextCancel = cancel
-	contextWithRouter := context.WithValue(routerContext, common.RouterContextKey, r)
-
-	for moduleId := range r.ModuleInstances {
-		// TODO(jwetzell): handle module run errors
-		err := r.startModule(contextWithRouter, moduleId)
-		if err != nil {
-			r.logger.Error("error starting module", "moduleId", moduleId, "error", err)
-		}
-	}
-	apiShutdownCtx, apiShutdownCancel := context.WithTimeout(context.Background(), 5*time.Second)
-
-	go func() {
-		r.apiServer = &http.Server{
-			Addr: fmt.Sprintf(":%d", r.runningConfig.Api.Port),
-		}
-		http.HandleFunc("/ws", r.handleWebsocket)
-		http.HandleFunc("/api/v1/config", r.handleConfigHTTP)
-		http.HandleFunc("/api/v1/schema/{schema}", r.handleSchemaHTTP)
-		r.logger.Debug("starting api server", "port", r.runningConfig.Api.Port)
-		r.apiServer.ListenAndServe()
-		apiShutdownCancel()
-	}()
+	r.startModules()
+	r.startAPIServer(r.runningConfig.Api)
 	<-r.Context.Done()
 	r.logger.Debug("shutting down api server")
-	r.apiServer.Shutdown(apiShutdownCtx)
-	<-apiShutdownCtx.Done()
+	r.stopAPIServer()
 	r.logger.Debug("waiting for modules to exit")
 	r.moduleWait.Wait()
 	r.logger.Info("done")
@@ -199,6 +181,9 @@ func (r *Router) Stop() {
 }
 
 func (r *Router) HandleInput(ctx context.Context, sourceId string, payload any) (bool, []common.RouteIOError) {
+	r.runningConfigMu.Lock()
+	defer r.runningConfigMu.Unlock()
+
 	spanCtx, span := otel.Tracer("router").Start(ctx, "input", trace.WithAttributes(attribute.String("source.id", sourceId)), trace.WithNewRoot())
 	defer span.End()
 	var routeIOErrors []common.RouteIOError
@@ -298,6 +283,83 @@ func (r *Router) HandleOutput(ctx context.Context, destinationId string, payload
 	return nil
 }
 
+func (r *Router) startModules() {
+	contextWithRouter := context.WithValue(r.Context, common.RouterContextKey, r)
+
+	for moduleId := range r.ModuleInstances {
+		// TODO(jwetzell): handle module run errors
+		err := r.startModule(contextWithRouter, moduleId)
+		if err != nil {
+			r.logger.Error("error starting module", "moduleId", moduleId, "error", err)
+		}
+	}
+}
+
 func (r *Router) RunningConfig() config.Config {
+	r.runningConfigMu.Lock()
+	defer r.runningConfigMu.Unlock()
 	return r.runningConfig
 }
+
+func (r *Router) UpdateConfig(newConfig config.Config) ([]module.ModuleError, []route.RouteError) {
+	r.runningConfigMu.Lock()
+	defer r.runningConfigMu.Unlock()
+	oldConfig := r.runningConfig
+	r.logger.Debug("received config update", "oldConfig", oldConfig, "newConfig", newConfig)
+
+	if !reflect.DeepEqual(oldConfig.Api, newConfig.Api) {
+		r.logger.Info("applying new API config")
+		r.stopAPIServer()
+		r.startAPIServer(newConfig.Api)
+		r.runningConfig.Api = newConfig.Api
+	}
+
+	// TODO(jwetzell): handle config update errors better
+	for _, moduleInstance := range r.ModuleInstances {
+		moduleInstance.Stop()
+	}
+	r.logger.Debug("waiting for modules to exit")
+	r.moduleWait.Wait()
+
+	r.ModuleInstances = make(map[string]module.Module)
+	r.RouteInstances = []*route.Route{}
+
+	var moduleErrors []module.ModuleError
+
+	for moduleIndex, moduleDecl := range newConfig.Modules {
+
+		err := r.addModule(moduleDecl)
+		if err != nil {
+			if moduleErrors == nil {
+				moduleErrors = []module.ModuleError{}
+			}
+			moduleErrors = append(moduleErrors, module.ModuleError{
+				Index:  moduleIndex,
+				Config: moduleDecl,
+				Error:  err.Error(),
+			})
+			continue
+		}
+
+	}
+
+	var routeErrors []route.RouteError
+	for routeIndex, routeDecl := range newConfig.Routes {
+		err := r.addRoute(routeDecl)
+		if err != nil {
+			if routeErrors == nil {
+				routeErrors = []route.RouteError{}
+			}
+			routeErrors = append(routeErrors, route.RouteError{
+				Index:  routeIndex,
+				Config: routeDecl,
+				Error:  err.Error(),
+			})
+			continue
+		}
+	}
+	r.runningConfig = newConfig
+	r.startModules()
+
+	return moduleErrors, routeErrors
+}

websocket.go

@@ -24,21 +24,39 @@ func (r *Router) handleWebsocket(w http.ResponseWriter, req *http.Request) {
 	r.wsConnsMu.Lock()
 	r.wsConns = append(r.wsConns, conn)
 	r.wsConnsMu.Unlock()
+READ_LOOP:
 	for {
-		_, message, err := conn.ReadMessage()
+		messageType, message, err := conn.ReadMessage()
 		if err != nil {
-			r.logger.Error("websocket read error", "error", err)
-			break
+			_, ok := err.(*websocket.CloseError)
+			if ok {
+				break READ_LOOP
+			}
 		}
 
-		event := Event{}
-		err = json.Unmarshal(message, &event)
-		if err != nil {
-			r.logger.Error("websocket message unmarshal error", "error", err)
+		switch messageType {
+		case websocket.TextMessage, websocket.BinaryMessage:
+			event := Event{}
+			err = json.Unmarshal(message, &event)
+			if err != nil {
+				r.logger.Error("websocket message unmarshal error", "error", err)
+				continue
+			}
+			r.handleEvent(event, conn)
+		case websocket.CloseMessage:
+			break READ_LOOP
+		case websocket.PingMessage:
+			err = conn.WriteMessage(websocket.PongMessage, nil)
+			if err != nil {
+				r.logger.Error("websocket pong error", "error", err)
+			}
+		default:
+			r.logger.Warn("unsupported websocket message type", "type", messageType)
 			continue
 		}
-		r.handleEvent(event)
+
 	}
+	//NOTE(jwetzell): remove ws connection
 	r.wsConnsMu.Lock()
 	for i, c := range r.wsConns {
 		if c == conn {