func getConfig(flagset *flag.FlagSet, userCfgFile string) (*config.Config, error) {
opts := globalconf.Options{EnvPrefix: "FLEET_"}
if userCfgFile != "" {
// Fail hard if a user-provided config is not usable
fi, err := os.Stat(userCfgFile)
if err != nil {
log.Fatalf("Unable to use config file %s: %v", userCfgFile, err)
}
if fi.IsDir() {
log.Fatalf("Provided config %s is a directory, not a file", userCfgFile)
}
log.Infof("Using provided config file %s", userCfgFile)
opts.Filename = userCfgFile
} else if _, err := os.Stat(DefaultConfigFile); err == nil {
log.Infof("Using default config file %s", DefaultConfigFile)
opts.Filename = DefaultConfigFile
} else {
log.Infof("No provided or default config file found - proceeding without")
}
gconf, err := globalconf.NewWithOptions(&opts)
if err != nil {
return nil, err
}
gconf.ParseSet("", flagset)
cfg := config.Config{
Verbosity: (*flagset.Lookup("verbosity")).Value.(flag.Getter).Get().(int),
EtcdServers: (*flagset.Lookup("etcd_servers")).Value.(flag.Getter).Get().(stringSlice),
EtcdKeyPrefix: (*flagset.Lookup("etcd_key_prefix")).Value.(flag.Getter).Get().(string),
PublicIP: (*flagset.Lookup("public_ip")).Value.(flag.Getter).Get().(string),
RawMetadata: (*flagset.Lookup("metadata")).Value.(flag.Getter).Get().(string),
AgentTTL: (*flagset.Lookup("agent_ttl")).Value.(flag.Getter).Get().(string),
VerifyUnits: (*flagset.Lookup("verify_units")).Value.(flag.Getter).Get().(bool),
AuthorizedKeysFile: (*flagset.Lookup("authorized_keys_file")).Value.(flag.Getter).Get().(string),
}
config.UpdateLoggingFlagsFromConfig(flag.CommandLine, &cfg)
return &cfg, nil
}
func main() {
// We use a FlagSets since glog adds a bunch of flags we do not want to publish
userset := flag.NewFlagSet("fleet", flag.ExitOnError)
printVersion := userset.Bool("version", false, "Print the version and exit")
cfgPath := userset.String("config", "", fmt.Sprintf("Path to config file. Fleet will look for a config at %s by default.", DefaultConfigFile))
// Initialize logging so we have it set up while parsing config information
config.UpdateLoggingFlagsFromConfig(flag.CommandLine, &config.Config{})
err := userset.Parse(os.Args[1:])
if err == flag.ErrHelp {
userset.Usage()
os.Exit(1)
}
if *printVersion {
fmt.Println("fleet version", version.Version)
os.Exit(0)
}
cfgset := flag.NewFlagSet("fleet", flag.ExitOnError)
cfgset.Int("verbosity", 0, "Logging level")
cfgset.Var(&stringSlice{}, "etcd_servers", "List of etcd endpoints")
cfgset.String("etcd_key_prefix", registry.DefaultKeyPrefix, "Keyspace for fleet data in etcd")
cfgset.String("public_ip", "", "IP address that fleet machine should publish")
cfgset.String("metadata", "", "List of key-value metadata to assign to the fleet machine")
cfgset.String("agent_ttl", agent.DefaultTTL, "TTL in seconds of fleet machine state in etcd")
cfgset.Bool("verify_units", false, "Verify unit file signatures using local SSH identities")
cfgset.String("authorized_keys_file", sign.DefaultAuthorizedKeysFile, "File containing public SSH keys to be used for signature verification")
globalconf.Register("", cfgset)
cfg, err := getConfig(cfgset, *cfgPath)
if err != nil {
log.Fatalf(err.Error())
}
log.V(1).Infof("Creating Server")
srv, err := server.New(*cfg)
if err != nil {
log.Fatalf("Failed creating Server: %v", err.Error())
}
srv.Run()
reconfigure := func() {
log.Infof("Reloading configuration from %s", *cfgPath)
cfg, err := getConfig(cfgset, *cfgPath)
if err != nil {
log.Fatalf(err.Error())
}
srv.Stop()
srv, err = server.New(*cfg)
if err != nil {
log.Fatalf(err.Error())
}
srv.Run()
}
shutdown := func() {
log.Infof("Gracefully shutting down")
srv.Stop()
srv.Purge()
os.Exit(0)
}
writeState := func() {
log.Infof("Dumping server state")
encoded, err := json.Marshal(srv)
if err != nil {
log.Errorf("Failed to dump server state: %v", err)
return
}
if _, err := os.Stdout.Write(encoded); err != nil {
log.Errorf("Failed to dump server state: %v", err)
return
}
os.Stdout.Write([]byte("\n"))
log.V(1).Infof("Finished dumping server state")
}
signals := map[os.Signal]func(){
syscall.SIGHUP: reconfigure,
syscall.SIGTERM: shutdown,
syscall.SIGINT: shutdown,
syscall.SIGUSR1: writeState,
}
listenForSignals(signals)
}