lib/http: add field Listener to ServerOptions

The field Listener allow user to pass [net.Listener] for accepting new
connection using [http.Serve] or [http.ServeTLS].

2 files changed, 16 insertions, 2 deletions

diff --git a/lib/http/server.go b/lib/http/server.go
index 4c89032b..76713308 100644
--- a/lib/http/server.go
+++ b/lib/http/server.go
@@ -352,9 +352,17 @@ func (srv *Server) ServeHTTP(res http.ResponseWriter, req *http.Request) {
 // Start the HTTP server.
 func (srv *Server) Start() (err error) {
 	if srv.Server.TLSConfig == nil {
-		err = srv.Server.ListenAndServe()
+		if srv.Options.Listener == nil {
+			err = srv.Server.ListenAndServe()
+		} else {
+			err = srv.Server.Serve(srv.Options.Listener)
+		}
 	} else {
-		err = srv.Server.ListenAndServeTLS("", "")
+		if srv.Options.Listener == nil {
+			err = srv.Server.ListenAndServeTLS(``, ``)
+		} else {
+			err = srv.Server.ServeTLS(srv.Options.Listener, ``, ``)
+		}
 	}
 	if errors.Is(err, http.ErrServerClosed) {
 		err = nil
diff --git a/lib/http/server_options.go b/lib/http/server_options.go
index 9ccb3e65..d51fe381 100644
--- a/lib/http/server_options.go
+++ b/lib/http/server_options.go
@@ -6,6 +6,7 @@ package http
 import (
 	"io"
 	"log"
+	"net"
 	"net/http"
 
 	"git.sr.ht/~shulhan/pakakeh.go/lib/memfs"
@@ -13,6 +14,11 @@ import (
 
 // ServerOptions define an options to initialize HTTP server.
 type ServerOptions struct {
+	// Listener define the network listener to be used for serving HTTP
+	// connection.
+	// The Listener can be activated using systemd socket.
+	Listener net.Listener
+
 	// Memfs contains the content of file systems to be served in memory.
 	// The MemFS instance to be served should be already embedded in Go
 	// file, generated using memfs.MemFS.GoEmbed().