unix socket support (#2974)

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* [x] I have added Go unit tests or [Complement integration
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Signed-off-by: `Boris Rybalkin <ribalkin@gmail.com>`

I need this for Syncloud project (https://github.com/syncloud/platform)
where I run multiple apps behind an nginx on the same RPi like device so
unix socket is very convenient to not have port conflicts between apps.
Also someone opened this Issue:
https://github.com/matrix-org/dendrite/issues/2924

---------

Co-authored-by: kegsay <kegan@matrix.org>
Co-authored-by: Till <2353100+S7evinK@users.noreply.github.com>

1 files changed, 25 insertions, 3 deletions

diff --git a/cmd/dendrite/main.go b/cmd/dendrite/main.go
index e8ff0a47..1ae348cf 100644
--- a/cmd/dendrite/main.go
+++ b/cmd/dendrite/main.go
@@ -16,6 +16,7 @@ package main
 
 import (
 	"flag"
+	"io/fs"
 
 	"github.com/sirupsen/logrus"
 
@@ -30,6 +31,12 @@ import (
 )
 
 var (
+	unixSocket = flag.String("unix-socket", "",
+		"EXPERIMENTAL(unstable): The HTTP listening unix socket for the server (disables http[s]-bind-address feature)",
+	)
+	unixSocketPermission = flag.Int("unix-socket-permission", 0755,
+		"EXPERIMENTAL(unstable): The HTTP listening unix socket permission for the server",
+	)
 	httpBindAddr  = flag.String("http-bind-address", ":8008", "The HTTP listening port for the server")
 	httpsBindAddr = flag.String("https-bind-address", ":8448", "The HTTPS listening port for the server")
 	certFile      = flag.String("tls-cert", "", "The PEM formatted X509 certificate to use for TLS")
@@ -38,8 +45,23 @@ var (
 
 func main() {
 	cfg := setup.ParseFlags(true)
-	httpAddr := config.HTTPAddress("http://" + *httpBindAddr)
-	httpsAddr := config.HTTPAddress("https://" + *httpsBindAddr)
+	httpAddr := config.ServerAddress{}
+	httpsAddr := config.ServerAddress{}
+	if *unixSocket == "" {
+		http, err := config.HTTPAddress("http://" + *httpBindAddr)
+		if err != nil {
+			logrus.WithError(err).Fatalf("Failed to parse http address")
+		}
+		httpAddr = http
+		https, err := config.HTTPAddress("https://" + *httpsBindAddr)
+		if err != nil {
+			logrus.WithError(err).Fatalf("Failed to parse https address")
+		}
+		httpsAddr = https
+	} else {
+		httpAddr = config.UnixSocketAddress(*unixSocket, fs.FileMode(*unixSocketPermission))
+	}
+
 	options := []basepkg.BaseDendriteOptions{}
 
 	base := basepkg.NewBaseDendrite(cfg, options...)
@@ -92,7 +114,7 @@ func main() {
 		base.SetupAndServeHTTP(httpAddr, nil, nil)
 	}()
 	// Handle HTTPS if certificate and key are provided
-	if *certFile != "" && *keyFile != "" {
+	if *unixSocket == "" && *certFile != "" && *keyFile != "" {
 		go func() {
 			base.SetupAndServeHTTP(httpsAddr, certFile, keyFile)
 		}()