Wait for plugin status via unix socket

prog/plugin/main.go

@@ -4,6 +4,7 @@ import (
 	"flag"
 	"fmt"
 	"net"
+	"net/http"
 	"os"
 	"os/signal"
 	"strings"
@@ -90,6 +91,7 @@ func main() {
 		createNetwork(dockerClient, meshNetworkName, meshAddress)
 	}
 
+	go listenAndServeStatus("/home/weave/status.sock")
 	sigChan := make(chan os.Signal, 1)
 	signal.Notify(sigChan, os.Interrupt, os.Kill, syscall.SIGTERM)
 
@@ -161,3 +163,19 @@ func createNetwork(dockerClient *docker.Client, networkName, address string) {
 		}
 	}
 }
+
+func listenAndServeStatus(socket string) {
+	if err := os.Remove(socket); err != nil && !os.IsNotExist(err) {
+		Log.Fatalf("Error removing existing status socket: %s", err)
+	}
+	listener, err := net.Listen("unix", socket)
+	if err != nil {
+		Log.Fatalf("ListenAndServeStatus failed: %s", err)
+	}
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintln(w, "ok")
+	})
+	if err := (&http.Server{Handler: handler}).Serve(listener); err != nil {
+		Log.Fatalf("ListenAndServeStatus failed: %s", err)
+	}
+}

weave

@@ -1698,6 +1698,7 @@ launch_plugin_if_not_running() {
         $(docker_sock_options) \
         -v /run/docker/plugins:/run/docker/plugins \
         $PLUGIN_IMAGE "$@")
+    wait_for_status $PLUGIN_CONTAINER_NAME http_call_unix $PLUGIN_CONTAINER_NAME status.sock
 }
 
 plugin_disabled() {
@@ -1880,8 +1881,6 @@ EOF
         ;;
     launch-plugin)
         launch_plugin_if_not_running "$@"
-        fractional_sleep 0.1
-        check_running $PLUGIN_CONTAINER_NAME 2>/dev/null || (death_msg $PLUGIN_CONTAINER_NAME ; exit 1)
         echo $PLUGIN_CONTAINER
         ;;
     env|proxy-env)