simplify unix socket permission format (#3014)

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* [x] I have added Go unit tests or [Complement integration
tests](https://github.com/matrix-org/complement) for this PR _or_ I have
justified why this PR doesn't need tests
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Signed-off-by: `Boris Rybalkin <ribalkin@gmail.com>`

3 files changed, 27 insertions, 4 deletions

diff --git a/setup/base/base_test.go b/setup/base/base_test.go
index 658dc5b0..aa406db2 100644
--- a/setup/base/base_test.go
+++ b/setup/base/base_test.go
@@ -76,7 +76,7 @@ func TestLandingPage_UnixSocket(t *testing.T) {
 	tempDir := t.TempDir()
 	socket := path.Join(tempDir, "socket")
 	// start base with the listener and wait for it to be started
-	address := config.UnixSocketAddress(socket, 0755)
+	address, err := config.UnixSocketAddress(socket, "755")
 	assert.NoError(t, err)
 	go b.SetupAndServeHTTP(address, nil, nil)
 	time.Sleep(time.Millisecond * 100)
diff --git a/setup/config/config_address.go b/setup/config/config_address.go
index 0e4f0296..a35cc3f9 100644
--- a/setup/config/config_address.go
+++ b/setup/config/config_address.go
@@ -3,6 +3,7 @@ package config
 import (
 	"io/fs"
 	"net/url"
+	"strconv"
 )
 
 const (
@@ -32,8 +33,12 @@ func (s ServerAddress) Network() string {
 	}
 }
 
-func UnixSocketAddress(path string, perm fs.FileMode) ServerAddress {
-	return ServerAddress{Address: path, Scheme: NetworkUnix, UnixSocketPermission: perm}
+func UnixSocketAddress(path string, perm string) (ServerAddress, error) {
+	permission, err := strconv.ParseInt(perm, 8, 32)
+	if err != nil {
+		return ServerAddress{}, err
+	}
+	return ServerAddress{Address: path, Scheme: NetworkUnix, UnixSocketPermission: fs.FileMode(permission)}, nil
 }
 
 func HTTPAddress(urlAddress string) (ServerAddress, error) {
diff --git a/setup/config/config_address_test.go b/setup/config/config_address_test.go
index 1be484fd..38c96ab7 100644
--- a/setup/config/config_address_test.go
+++ b/setup/config/config_address_test.go
@@ -20,6 +20,24 @@ func TestHttpAddress_ParseBad(t *testing.T) {
 }
 
 func TestUnixSocketAddress_Network(t *testing.T) {
-	address := UnixSocketAddress("/tmp", fs.FileMode(0755))
+	address, err := UnixSocketAddress("/tmp", "0755")
+	assert.NoError(t, err)
 	assert.Equal(t, "unix", address.Network())
 }
+
+func TestUnixSocketAddress_Permission_LeadingZero_Ok(t *testing.T) {
+	address, err := UnixSocketAddress("/tmp", "0755")
+	assert.NoError(t, err)
+	assert.Equal(t, fs.FileMode(0755), address.UnixSocketPermission)
+}
+
+func TestUnixSocketAddress_Permission_NoLeadingZero_Ok(t *testing.T) {
+	address, err := UnixSocketAddress("/tmp", "755")
+	assert.NoError(t, err)
+	assert.Equal(t, fs.FileMode(0755), address.UnixSocketPermission)
+}
+
+func TestUnixSocketAddress_Permission_NonOctal_Bad(t *testing.T) {
+	_, err := UnixSocketAddress("/tmp", "855")
+	assert.Error(t, err)
+}