Basic server app with WS connection.

server/internal/services/core/httpserver/httpserver.go

@@ -0,0 +1,91 @@
+package httpserver
+
+import (
+	"errors"
+	"fmt"
+	"log/slog"
+	"net/http"
+
+	"bunker/server/internal/application"
+	"bunker/server/internal/services/core"
+)
+
+var (
+	_ = core.HTTPServer(&httpServer{})
+
+	errHTTPServer = errors.New("HTTP server core service")
+)
+
+type httpServer struct {
+	app     *application.Application
+	logger  *slog.Logger
+	db      core.Database
+	httpSrv *http.Server
+}
+
+// Initialize initializes service.
+func Initialize(app *application.Application) error {
+	httpSrv := &httpServer{
+		app: app,
+	}
+
+	if err := app.RegisterService(httpSrv); err != nil {
+		return fmt.Errorf("%w: %w", errHTTPServer, err)
+	}
+
+	return nil
+}
+
+func (h *httpServer) Configure() error {
+	h.logger.Debug("Configuring service...")
+
+	if err := h.configureHTTPServer(); err != nil {
+		return fmt.Errorf("configure: %w", err)
+	}
+
+	return nil
+}
+
+func (h *httpServer) ConnectDependencies() error {
+	databaseRaw := h.app.Service(core.ServiceNameDatabase)
+	if databaseRaw == nil {
+		return fmt.Errorf("connect dependencies: get database service: %w", application.ErrServiceNotFound)
+	}
+
+	database, valid := databaseRaw.(core.Database)
+	if !valid {
+		return fmt.Errorf("connect dependencies: type assert database service: %w", core.ErrDatabaseIsInvalid)
+	}
+
+	h.db = database
+
+	return nil
+}
+
+func (h *httpServer) Initialize() error {
+	h.logger = h.app.NewLogger("service", core.ServiceNameHTTPServer)
+
+	h.logger.Info("Initializing...")
+
+	return nil
+}
+
+func (h *httpServer) Name() string {
+	return core.ServiceNameHTTPServer
+}
+
+func (h *httpServer) LaunchStartupTasks() error {
+	h.logger.Debug("Launching startup tasks...")
+
+	go h.startHTTPServer()
+
+	return nil
+}
+
+func (h *httpServer) Shutdown() error {
+	if err := h.stopHTTPServer(); err != nil {
+		return fmt.Errorf("%w: Shutdown: %w", errHTTPServer, err)
+	}
+
+	return nil
+}

server/internal/services/core/httpserver/server.go

@@ -0,0 +1,85 @@
+package httpserver
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/coder/websocket"
+)
+
+const httpServerAddrEnvVar = "BUNKERD_HTTP_ADDRESS"
+
+var (
+	errHTTPServerAddrInvalid = errors.New("BUNKERD_HTTP_ADDRESS environment variable contains invalid address to " +
+		"listen, should be 'host:port'")
+	errHTTPServerAddrNotFound = errors.New("BUNKERD_HTTP_ADDRESS environment variable empty")
+)
+
+func (h *httpServer) configureHTTPServer() error {
+	httpSrvAddr, found := os.LookupEnv(httpServerAddrEnvVar)
+	if !found {
+		return fmt.Errorf("configure HTTP server: get address from environment variable: %w", errHTTPServerAddrNotFound)
+	}
+
+	host, port, err := net.SplitHostPort(httpSrvAddr)
+	if err != nil {
+		return fmt.Errorf("configure HTTP server: validate HTTP server address: %w", err)
+	}
+
+	if httpSrvAddr != host+":"+port {
+		return fmt.Errorf("configure HTTP server: validate HTTP server address: %w", errHTTPServerAddrInvalid)
+	}
+
+	mux := new(http.ServeMux)
+	mux.HandleFunc("GET /api/v1/socket", h.handleWebsocketRequest)
+
+	h.httpSrv = &http.Server{
+		Addr:              httpSrvAddr,
+		Handler:           mux,
+		ReadHeaderTimeout: time.Second * 3,
+	}
+
+	return nil
+}
+
+func (h *httpServer) handleWebsocketRequest(w http.ResponseWriter, r *http.Request) {
+	wsConn, err := websocket.Accept(w, r, &websocket.AcceptOptions{
+		OnPingReceived: func(_ context.Context, _ []byte) bool {
+			return true
+		},
+	})
+	if err != nil {
+		h.logger.Error("Failed to accept WS connection!", "error", err.Error())
+
+		return
+	}
+
+	defer func() {
+		if err := wsConn.CloseNow(); err != nil {
+			h.logger.Warn("Failed to close WS connection in defer!", "error", err.Error())
+		}
+	}()
+}
+
+func (h *httpServer) startHTTPServer() {
+	h.logger.Info("Starting listening for HTTP requests.", "address", h.httpSrv.Addr)
+
+	if err := h.httpSrv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
+		h.logger.Warn("Error when listening to ", "error", err.Error())
+	}
+}
+
+func (h *httpServer) stopHTTPServer() error {
+	h.logger.Info("Stopping HTTP server...")
+
+	if err := h.httpSrv.Shutdown(h.app.ContextWithTimeout(time.Second * 3)); err != nil {
+		return fmt.Errorf("stopping HTTP server: %w", err)
+	}
+
+	return nil
+}