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>

3 files changed, 70 insertions, 15 deletions

diff --git a/setup/config/config.go b/setup/config/config.go
index 84876616..1a25f71e 100644
--- a/setup/config/config.go
+++ b/setup/config/config.go
@@ -19,7 +19,6 @@ import (
 	"encoding/pem"
 	"fmt"
 	"io"
-	"net/url"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -131,20 +130,6 @@ func (d DataSource) IsPostgres() bool {
 // A Topic in kafka.
 type Topic string
 
-// An Address to listen on.
-type Address string
-
-// An HTTPAddress to listen on, starting with either http:// or https://.
-type HTTPAddress string
-
-func (h HTTPAddress) Address() (Address, error) {
-	url, err := url.Parse(string(h))
-	if err != nil {
-		return "", err
-	}
-	return Address(url.Host), nil
-}
-
 // FileSizeBytes is a file size in bytes
 type FileSizeBytes int64
 
diff --git a/setup/config/config_address.go b/setup/config/config_address.go
new file mode 100644
index 00000000..0e4f0296
--- /dev/null
+++ b/setup/config/config_address.go
@@ -0,0 +1,45 @@
+package config
+
+import (
+	"io/fs"
+	"net/url"
+)
+
+const (
+	NetworkTCP  = "tcp"
+	NetworkUnix = "unix"
+)
+
+type ServerAddress struct {
+	Address              string
+	Scheme               string
+	UnixSocketPermission fs.FileMode
+}
+
+func (s ServerAddress) Enabled() bool {
+	return s.Address != ""
+}
+
+func (s ServerAddress) IsUnixSocket() bool {
+	return s.Scheme == NetworkUnix
+}
+
+func (s ServerAddress) Network() string {
+	if s.Scheme == NetworkUnix {
+		return NetworkUnix
+	} else {
+		return NetworkTCP
+	}
+}
+
+func UnixSocketAddress(path string, perm fs.FileMode) ServerAddress {
+	return ServerAddress{Address: path, Scheme: NetworkUnix, UnixSocketPermission: perm}
+}
+
+func HTTPAddress(urlAddress string) (ServerAddress, error) {
+	parsedUrl, err := url.Parse(urlAddress)
+	if err != nil {
+		return ServerAddress{}, err
+	}
+	return ServerAddress{parsedUrl.Host, parsedUrl.Scheme, 0}, nil
+}
diff --git a/setup/config/config_address_test.go b/setup/config/config_address_test.go
new file mode 100644
index 00000000..1be484fd
--- /dev/null
+++ b/setup/config/config_address_test.go
@@ -0,0 +1,25 @@
+package config
+
+import (
+	"io/fs"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestHttpAddress_ParseGood(t *testing.T) {
+	address, err := HTTPAddress("http://localhost:123")
+	assert.NoError(t, err)
+	assert.Equal(t, "localhost:123", address.Address)
+	assert.Equal(t, "tcp", address.Network())
+}
+
+func TestHttpAddress_ParseBad(t *testing.T) {
+	_, err := HTTPAddress(":")
+	assert.Error(t, err)
+}
+
+func TestUnixSocketAddress_Network(t *testing.T) {
+	address := UnixSocketAddress("/tmp", fs.FileMode(0755))
+	assert.Equal(t, "unix", address.Network())
+}