func (s *Server) Start() error {
var err error
sl, err := net.Listen("tcp", s.conf.SyslogAddr)
if err != nil {
return err
}
s.syslogListener = keepalive.Listener(sl)
al, err := net.Listen("tcp", s.conf.ApiAddr)
if err != nil {
return err
}
s.apiListener = keepalive.Listener(al)
if s.conf.Discoverd != nil {
s.hb, err = s.conf.Discoverd.AddServiceAndRegister(s.conf.ServiceName, s.conf.SyslogAddr)
if err != nil {
return err
}
}
go s.runSyslog()
go http.Serve(s.apiListener, s.api)
return nil
}
func httpServer(sn *subnet.SubnetManager, publicIP, port string) error {
overlayListener, err := net.Listen("tcp", net.JoinHostPort(sn.Lease().Network.IP.String(), port))
if err != nil {
return err
}
publicListener, err := net.Listen("tcp", net.JoinHostPort(publicIP, port))
http.HandleFunc("/ping", func(http.ResponseWriter, *http.Request) {})
status.AddHandler(status.SimpleHandler(func() error {
return pingLeases(sn.Leases())
}))
go http.Serve(keepalive.Listener(overlayListener), nil)
go http.Serve(keepalive.Listener(publicListener), nil)
return nil
}
// Run executes the program.
func (m *Main) Run() error {
m.Logger.Info("running")
// Read or generate the instance identifier from file.
id, err := m.readID(filepath.Join(m.DataDir, "instance_id"))
if err != nil {
return err
}
m.Process.ID = id
m.Process.DataDir = m.DataDir
m.Process.Logger = m.Logger.New("component", "process", "id", id)
// Start process.
m.Logger.Info("starting process", "id", id)
if err := m.Process.Start(); err != nil {
m.Logger.Error("error starting process", "err", err)
return err
}
// Add service to discoverd registry.
m.Logger.Info("adding service", "name", m.ServiceName)
if err = m.DiscoverdClient.AddService(m.ServiceName, nil); err != nil && !httphelper.IsObjectExistsError(err) {
m.Logger.Error("error adding discoverd service", "err", err)
return err
}
inst := &discoverd.Instance{
Addr: ":" + m.Process.Port,
Meta: map[string]string{"REDIS_ID": id},
}
// Register instance and retain heartbeater.
m.Logger.Info("registering instance", "addr", inst.Addr, "meta", inst.Meta)
hb, err := m.DiscoverdClient.RegisterInstance(m.ServiceName, inst)
if err != nil {
m.Logger.Error("error registering discoverd instance", "err", err)
return err
}
m.hb = hb
shutdown.BeforeExit(func() { hb.Close() })
m.Logger.Info("opening port", "addr", m.Addr)
// Open HTTP port.
ln, err := net.Listen("tcp", m.Addr)
if err != nil {
m.Logger.Error("error opening port", "err", err)
return err
}
m.ln = keepalive.Listener(ln)
// Initialize and server handler.
m.Logger.Info("serving http api")
h := redis.NewHandler()
h.Process = m.Process
h.Heartbeater = m.hb
h.Logger = m.Logger.New("component", "http")
go func() { http.Serve(ln, h) }()
return nil
}
func newHTTPListener(addr string) (net.Listener, error) {
fdEnv := os.Getenv("FLYNN_HTTP_FD")
if fdEnv == "" {
l, err := net.Listen("tcp", addr)
if err != nil {
return nil, err
}
return keepalive.Listener(l), nil
}
fd, err := strconv.Atoi(fdEnv)
if err != nil {
return nil, err
}
file := os.NewFile(uintptr(fd), "http")
defer file.Close()
return net.FileListener(file)
}
// Run executes the program.
func (m *Main) Run(args ...string) error {
// Create logger.
m.logger = log.New(m.Stdout, "", log.LstdFlags)
// Parse command line flags.
opt, err := m.ParseFlags(args...)
if err != nil {
return err
}
// Set up advertised address and default peer set.
m.advertiseAddr = MergeHostPort(opt.Host, opt.Addr)
if len(opt.Peers) == 0 {
opt.Peers = []string{m.advertiseAddr}
}
// Create a slice of peers with their HTTP address set instead.
httpPeers, err := SetPortSlice(opt.Peers, opt.Addr)
if err != nil {
return fmt.Errorf("set port slice: %s", err)
}
m.peers = httpPeers
// Initialise the default client using the peer list
os.Setenv("DISCOVERD", strings.Join(opt.Peers, ","))
discoverd.DefaultClient = discoverd.NewClient()
// if there is a discoverd process already running on this
// address perform a deployment by starting a proxy DNS server
// and shutting down the old discoverd job
var deploy *dd.Deployment
var targetLogIndex dt.TargetLogIndex
target := fmt.Sprintf("http://%s:1111", opt.Host)
m.logger.Println("checking for existing discoverd process at", target)
if err := discoverd.NewClientWithURL(target).Ping(target); err == nil {
m.logger.Println("discoverd responding at", target, "taking over")
deploy, err = dd.NewDeployment("discoverd")
if err != nil {
return err
}
m.logger.Println("Created deployment")
if err := deploy.MarkPerforming(m.advertiseAddr, 60); err != nil {
return err
}
m.logger.Println("marked", m.advertiseAddr, "as performing in deployent")
addr, resolvers := waitHostDNSConfig()
if opt.DNSAddr != "" {
addr = opt.DNSAddr
}
if len(opt.Recursors) > 0 {
resolvers = opt.Recursors
}
m.logger.Println("starting proxy DNS server")
if err := m.openDNSServer(addr, resolvers); err != nil {
return fmt.Errorf("Failed to start DNS server: %s", err)
}
m.logger.Printf("discoverd listening for DNS on %s", addr)
targetLogIndex, err = discoverd.NewClientWithURL(target).Shutdown(target)
if err != nil {
return err
}
// Sleep for 2x the election timeout.
// This is to work around an issue with hashicorp/raft that can allow us to be elected with
// no log entries, hence truncating the log and losing all data!
time.Sleep(2 * time.Second)
} else {
m.logger.Println("failed to contact existing discoverd server, starting up without takeover")
m.logger.Println("err:", err)
}
// Open listener.
ln, err := net.Listen("tcp4", opt.Addr)
if err != nil {
return err
}
m.ln = keepalive.Listener(ln)
// Open mux
m.mux = mux.New(m.ln)
go m.mux.Serve()
m.dataDir = opt.DataDir
// if the advertise addr is not in the peer list we are proxying
proxying := true
for _, addr := range m.peers {
if addr == m.advertiseAddr {
proxying = false
break
}
}
if proxying {
// Notify user that we're proxying if the store wasn't initialized.
m.logger.Println("advertised address not in peer set, joining as proxy")
} else {
// Open store if we are not proxying.
if err := m.openStore(); err != nil {
return fmt.Errorf("Failed to open store: %s", err)
}
}
// Wait for the store to catchup before switching to local store if we are doing a deployment
if m.store != nil && targetLogIndex.LastIndex > 0 {
for m.store.LastIndex() < targetLogIndex.LastIndex {
m.logger.Println("Waiting for store to catchup, current:", m.store.LastIndex(), "target:", targetLogIndex.LastIndex)
time.Sleep(100 * time.Millisecond)
}
}
// If we already started the DNS server as part of a deployment above,
// and we have an initialized store, just switch from the proxy store
// to the initialized store.
//
// Else if we have a DNS address, start a DNS server right away.
//
// Otherwise wait for the host network to come up and then start a DNS
// server.
if m.dnsServer != nil && m.store != nil {
m.dnsServer.SetStore(m.store)
} else if opt.DNSAddr != "" {
if err := m.openDNSServer(opt.DNSAddr, opt.Recursors); err != nil {
return fmt.Errorf("Failed to start DNS server: %s", err)
}
m.logger.Printf("discoverd listening for DNS on %s", opt.DNSAddr)
} else if opt.WaitNetDNS {
go func() {
addr, resolvers := waitHostDNSConfig()
m.mu.Lock()
if err := m.openDNSServer(addr, resolvers); err != nil {
log.Fatalf("Failed to start DNS server: %s", err)
}
m.mu.Unlock()
m.logger.Printf("discoverd listening for DNS on %s", addr)
// Notify webhook.
if opt.Notify != "" {
m.Notify(opt.Notify, addr)
}
}()
}
if err := m.openHTTPServer(); err != nil {
return fmt.Errorf("Failed to start HTTP server: %s", err)
}
if deploy != nil {
if err := deploy.MarkDone(m.advertiseAddr); err != nil {
return err
}
m.logger.Println("marked", m.advertiseAddr, "as done in deployment")
}
// Notify user that the servers are listening.
m.logger.Printf("discoverd listening for HTTP on %s", opt.Addr)
// Wait for leadership.
if err := m.waitForLeader(IndefiniteTimeout); err != nil {
return err
}
// Notify URL that discoverd is running.
httpAddr := ln.Addr().String()
host, port, _ := net.SplitHostPort(httpAddr)
if host == "0.0.0.0" {
httpAddr = net.JoinHostPort(os.Getenv("EXTERNAL_IP"), port)
}
m.Notify(opt.Notify, opt.DNSAddr)
go func() {
for {
hb, err := discoverd.AddServiceAndRegister("discoverd", httpAddr)
if err != nil {
m.logger.Println("failed to register service/instance, retrying in 5 seconds:", err)
time.Sleep(5 * time.Second)
continue
}
m.mu.Lock()
m.hb = hb
m.mu.Unlock()
break
}
}()
return nil
}