func main() { flag.Parse() if verFlag { fmt.Printf("%s\n", version) return } // Setup context ctx := context.Background() ctx = log.NewContext(ctx) log.Log(ctx).Info("Starting quicklog") // Setup system system := managed.NewSystem("quicklog") system.StartWithContext(ctx) // Register signal listeners system.RegisterForStop(os.Interrupt, os.Kill) switch { case etcdEndpoints != "" && instanceName != "": startEtcdQuicklog(ctx, system) case configFile != "": startFileQuicklog(ctx, system) } system.Wait() }
func main() { system := managed.NewSystem("app1") system.Start() sender := make(chan int) accum := make(chan int) go func() { a := 0 for i := 0; i < 5; i++ { select { case val := <-accum: a += val } } fmt.Printf("Got: %d\n", a) }() for _, i := range []int{1, 2, 3, 4, 5} { name := "my." + strconv.FormatInt(int64(i), 10) x := managed.Simple("my."+strconv.FormatInt(int64(i), 10), mySubprocessFactory(name, sender, accum)) system.Add(x) } system.Add(managed.Timer("printer", 3*time.Millisecond, true, func(ctx context.Context) { system.WriteTree(managed.TextWriter(os.Stdout, 1)) system.Stop() })) go func() { sender <- 1 sender <- 2 sender <- 3 sender <- 4 sender <- 5 }() system.Wait() }
func startEtcdQuicklog(mainCtx context.Context, system *managed.System) { log.Log(mainCtx).Info("Loading config from etcd") log.Log(mainCtx).Debug("Connecting to endpoint", "endpoints", strings.Split(etcdEndpoints, ",")) etcdCfg := client.Config{ Endpoints: strings.Split(etcdEndpoints, ","), } c, err := client.New(etcdCfg) if err != nil { log.Log(mainCtx).Crit("Error connecting to etcd server", "error", err) return } root := "/quicklog/" + instanceName log.Log(mainCtx).Debug("Listening for etcd keys", "key", root) kapi := client.NewKeysAPI(c) chainApp := managed.NewSystem("app-chain-" + instanceName) system.SpawnSystem(chainApp) var cfg config.Config err = syncFromEtcd(mainCtx, root, kapi, &cfg) if err != nil { log.Log(mainCtx).Error("Error syncing from etcd", "error", err) } // setup chain chain := fromConfig(mainCtx, &cfg) chainApp.Add(managed.Simple("chain-sub-"+instanceName, chain.Execute)) system.Add(managed.Simple("etcd", func(ctx context.Context) { w := kapi.Watcher(root+"/reload", &client.WatcherOptions{ Recursive: false, }) for { resp, err := w.Next(ctx) if err != nil { if err == context.DeadlineExceeded { continue } else if err == context.Canceled { return } else if cerr, ok := err.(*client.ClusterError); ok { for _, e := range cerr.Errors { if e != context.Canceled { log.Log(ctx).Error("Error getting next etcd watch event", "parentError", err, "error", e) } } } else { log.Log(ctx).Error("Error getting next etcd watch event", "error", err) } return } if resp == nil { return } switch resp.Action { case "get": // do nothing default: log.Log(ctx).Info("Got update on quicklog config", "etcd.action", resp.Action) var newCfg config.Config err = syncFromEtcd(ctx, root, kapi, &newCfg) if err != nil { log.Log(ctx).Error("Error syncing from etcd", "error", err) } else { chainApp.Stop() <-time.After(1 * time.Second) chainApp = managed.NewSystem("app-chain-" + instanceName) system.SpawnSystem(chainApp) // setup chain chain = fromConfig(ctx, &newCfg) chainApp.Add(managed.Simple("chain-sub-"+instanceName, chain.Execute)) } //TODO: (re)load config } } })) }