Merge remote-tracking branch 'origin/main' into feat/custom-fields

backend/internal/bootstrap/router_bootstrap.go

@@ -15,6 +15,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/coreos/go-systemd/activation"
 	"github.com/fsnotify/fsnotify"
 	sloggin "github.com/gin-contrib/slog"
 	"github.com/gin-gonic/gin"
@@ -162,24 +163,26 @@ func initServer(r *gin.Engine) (*serverConfig, error) {
 		return nil, err
 	}
 
-	network, addr := listenerNetworkAndAddr()
-	listener, err := net.Listen(network, addr) //nolint:noctx
-	if err != nil {
-		return nil, fmt.Errorf("failed to create %s listener: %w", network, err)
+	var socketFn func() (*socket, error)
+	switch {
+	case common.EnvConfig.SystemdSocket:
+		socketFn = systemdSocket
+	case common.EnvConfig.UnixSocket != "":
+		socketFn = unixSocket
+	default:
+		socketFn = tcpSocket
 	}
 
-	if err := setUnixSocketMode(network, addr); err != nil {
-		listener.Close()
+	socket, err := socketFn()
+	if err != nil {
 		return nil, err
 	}
 
-	return &serverConfig{
-		addr:         addr,
-		certProvider: certProvider,
-		listener:     listener,
-		server:       newHTTPServer(r, protocols),
-		tlsConfig:    tlsConfig,
-	}, nil
+	addr := socket.addr
+	listener := socket.listener
+	server := newHTTPServer(r, protocols)
+
+	return &serverConfig{addr, certProvider, listener, server, tlsConfig}, nil
 }
 
 func initServerProtocols() (*http.Protocols, *tls.Config, *tlsCertProvider, error) {
@@ -207,6 +210,64 @@ func initServerProtocols() (*http.Protocols, *tls.Config, *tlsCertProvider, erro
 	return protocols, tlsConfig, certProvider, nil
 }
 
+type socket struct {
+	addr     string
+	listener net.Listener
+}
+
+func systemdSocket() (*socket, error) {
+	listeners, err := activation.Listeners()
+	if err != nil {
+		return nil, fmt.Errorf("failed to receive socket from systemd: %w", err)
+	}
+
+	if len(listeners) == 0 {
+		return nil, errors.New("did not receive any sockets from systemd")
+	}
+
+	if len(listeners) > 1 {
+		return nil, errors.New("received too many sockets from systemd")
+	}
+
+	return &socket{"(systemd)", listeners[0]}, nil
+}
+
+func unixSocket() (*socket, error) {
+	addr := common.EnvConfig.UnixSocket
+	os.Remove(addr) // remove dangling the socket file to avoid file-exist error
+
+	listener, err := net.Listen("unix", addr) //nolint:noctx
+	if err != nil {
+		return nil, fmt.Errorf("failed to create UNIX socket: %w", err)
+	}
+
+	if common.EnvConfig.UnixSocketMode != "" {
+		mode, err := strconv.ParseUint(common.EnvConfig.UnixSocketMode, 8, 32)
+		if err != nil {
+			listener.Close()
+			return nil, fmt.Errorf("failed to parse UNIX socket mode '%s': %w", common.EnvConfig.UnixSocketMode, err)
+		}
+
+		if err := os.Chmod(addr, os.FileMode(mode)); err != nil {
+			listener.Close()
+			return nil, fmt.Errorf("failed to set UNIX socket mode '%s': %w", common.EnvConfig.UnixSocketMode, err)
+		}
+	}
+
+	return &socket{addr, listener}, nil
+}
+
+func tcpSocket() (*socket, error) {
+	addr := net.JoinHostPort(common.EnvConfig.Host, common.EnvConfig.Port)
+
+	listener, err := net.Listen("tcp", addr) //nolint:noctx
+	if err != nil {
+		return nil, fmt.Errorf("failed to create TCP socket: %w", err)
+	}
+
+	return &socket{addr, listener}, nil
+}
+
 func newHTTPServer(r *gin.Engine, protocols *http.Protocols) *http.Server {
 	return &http.Server{
 		MaxHeaderBytes:    1 << 20,
@@ -226,33 +287,6 @@ func newHTTPServer(r *gin.Engine, protocols *http.Protocols) *http.Server {
 	}
 }
 
-func listenerNetworkAndAddr() (string, string) {
-	if common.EnvConfig.UnixSocket == "" {
-		return "tcp", net.JoinHostPort(common.EnvConfig.Host, common.EnvConfig.Port)
-	}
-
-	addr := common.EnvConfig.UnixSocket
-	os.Remove(addr) // remove dangling the socket file to avoid file-exist error
-	return "unix", addr
-}
-
-func setUnixSocketMode(network, addr string) error {
-	if network != "unix" || common.EnvConfig.UnixSocketMode == "" {
-		return nil
-	}
-
-	mode, err := strconv.ParseUint(common.EnvConfig.UnixSocketMode, 8, 32)
-	if err != nil {
-		return fmt.Errorf("failed to parse UNIX socket mode '%s': %w", common.EnvConfig.UnixSocketMode, err)
-	}
-
-	if err := os.Chmod(addr, os.FileMode(mode)); err != nil {
-		return fmt.Errorf("failed to set UNIX socket mode '%s': %w", common.EnvConfig.UnixSocketMode, err)
-	}
-
-	return nil
-}
-
 func runServer(ctx context.Context, config *serverConfig) error {
 	slog.Info("Server listening", slog.String("addr", config.addr), slog.Bool("tls", config.tlsConfig != nil))