fix: clean up Unix socket file before exit

If webhook is restarted with the same settings but the socket file has not been deleted, webhook will be unable to bind and will exit with an error.

signals.go

@@ -1,3 +1,4 @@
+//go:build !windows
 // +build !windows
 
 package main
@@ -6,6 +7,7 @@ import (
 	"log"
 	"os"
 	"os/signal"
+	"strings"
 	"syscall"
 )
 
@@ -43,6 +45,15 @@ func watchForSignals() {
 					log.Print(err)
 				}
 			}
+			if socket != "" && !strings.HasPrefix(socket, "@") {
+				// we've been listening on a named Unix socket, delete it
+				// before we exit so subsequent runs can re-bind the same
+				// socket path
+				err := os.Remove(socket)
+				if err != nil {
+					log.Printf("Failed to remove socket file %s: %v", socket, err)
+				}
+			}
 			os.Exit(0)
 
 		default: