Golang Config.Value方法代码示例

func (a *MachineAgent) uninstallAgent(agentConfig agent.Config) error {
	var errors []error
	agentServiceName := agentConfig.Value(agent.AgentServiceName)
	if agentServiceName == "" {
		// For backwards compatibility, handle lack of AgentServiceName.
		agentServiceName = os.Getenv("UPSTART_JOB")
	}
	if agentServiceName != "" {
		if err := upstart.NewService(agentServiceName).Remove(); err != nil {
			errors = append(errors, fmt.Errorf("cannot remove service %q: %v", agentServiceName, err))
		}
	}
	// Remove the juju-run symlink.
	if err := os.Remove(jujuRun); err != nil && !os.IsNotExist(err) {
		errors = append(errors, err)
	}

	namespace := agentConfig.Value(agent.Namespace)
	if err := mongo.RemoveService(namespace); err != nil {
		errors = append(errors, fmt.Errorf("cannot stop/remove mongo service with namespace %q: %v", namespace, err))
	}
	if err := os.RemoveAll(agentConfig.DataDir()); err != nil {
		errors = append(errors, err)
	}
	if len(errors) == 0 {
		return nil
	}
	return fmt.Errorf("uninstall failed: %v", errors)
}

func (c *BootstrapCommand) startMongo(addrs []instance.Address, agentConfig agent.Config) error {
	logger.Debugf("starting mongo")

	info, ok := agentConfig.StateInfo()
	if !ok {
		return fmt.Errorf("no state info available")
	}
	// When bootstrapping, we need to allow enough time for mongo
	// to start as there's no retry loop in place.
	// 5 minutes should suffice.
	bootstrapDialOpts := state.DialOpts{Timeout: 5 * time.Minute}
	dialInfo, err := state.DialInfo(info, bootstrapDialOpts)
	if err != nil {
		return err
	}
	servingInfo, ok := agentConfig.StateServingInfo()
	if !ok {
		return fmt.Errorf("agent config has no state serving info")
	}
	// Use localhost to dial the mongo server, because it's running in
	// auth mode and will refuse to perform any operations unless
	// we dial that address.
	dialInfo.Addrs = []string{
		net.JoinHostPort("127.0.0.1", fmt.Sprint(servingInfo.StatePort)),
	}

	logger.Debugf("calling ensureMongoServer")
	err = ensureMongoServer(
		agentConfig.DataDir(),
		agentConfig.Value(agent.Namespace),
		servingInfo,
	)
	if err != nil {
		return err
	}

	peerAddr := mongo.SelectPeerAddress(addrs)
	if peerAddr == "" {
		return fmt.Errorf("no appropriate peer address found in %q", addrs)
	}
	peerHostPort := net.JoinHostPort(peerAddr, fmt.Sprint(servingInfo.StatePort))

	return maybeInitiateMongoServer(peergrouper.InitiateMongoParams{
		DialInfo:       dialInfo,
		MemberHostPort: peerHostPort,
	})
}

func (a *MachineAgent) ensureMongoAdminUser(agentConfig agent.Config) (added bool, err error) {
	stateInfo, ok1 := agentConfig.StateInfo()
	servingInfo, ok2 := agentConfig.StateServingInfo()
	if !ok1 || !ok2 {
		return false, fmt.Errorf("no state serving info configuration")
	}
	dialInfo, err := state.DialInfo(stateInfo, state.DefaultDialOpts())
	if err != nil {
		return false, err
	}
	if len(dialInfo.Addrs) > 1 {
		logger.Infof("more than one state server; admin user must exist")
		return false, nil
	}
	return ensureMongoAdminUser(mongo.EnsureAdminUserParams{
		DialInfo:  dialInfo,
		Namespace: agentConfig.Value(agent.Namespace),
		DataDir:   agentConfig.DataDir(),
		Port:      servingInfo.StatePort,
		User:      stateInfo.Tag,
		Password:  stateInfo.Password,
	})
}

func containerManagerConfig(
	containerType instance.ContainerType,
	provisioner *apiprovisioner.State,
	agentConfig agent.Config,
) (container.ManagerConfig, error) {
	// Ask the provisioner for the container manager configuration.
	managerConfigResult, err := provisioner.ContainerManagerConfig(
		params.ContainerManagerConfigParams{Type: containerType},
	)
	if params.IsCodeNotImplemented(err) {
		// We currently don't support upgrading;
		// revert to the old configuration.
		managerConfigResult.ManagerConfig = container.ManagerConfig{container.ConfigName: "juju"}
	}
	if err != nil {
		return nil, err
	}
	// If a namespace is specified, that should instead be used as the config name.
	if namespace := agentConfig.Value(agent.Namespace); namespace != "" {
		managerConfigResult.ManagerConfig[container.ConfigName] = namespace
	}
	managerConfig := container.ManagerConfig(managerConfigResult.ManagerConfig)
	return managerConfig, nil
}

// ensureMongoServer ensures that mongo is installed and running,
// and ready for opening a state connection.
func (a *MachineAgent) ensureMongoServer(agentConfig agent.Config) error {
	servingInfo, ok := agentConfig.StateServingInfo()
	if !ok {
		return fmt.Errorf("state worker was started with no state serving info")
	}
	namespace := agentConfig.Value(agent.Namespace)

	// When upgrading from a pre-HA-capable environment,
	// we must add machine-0 to the admin database and
	// initiate its replicaset.
	//
	// TODO(axw) remove this when we no longer need
	// to upgrade from pre-HA-capable environments.
	var shouldInitiateMongoServer bool
	var addrs []instance.Address
	if isPreHAVersion(agentConfig.UpgradedToVersion()) {
		_, err := a.ensureMongoAdminUser(agentConfig)
		if err != nil {
			return err
		}
		if servingInfo.SharedSecret == "" {
			servingInfo.SharedSecret, err = mongo.GenerateSharedSecret()
			if err != nil {
				return err
			}
			if err = a.ChangeConfig(func(config agent.ConfigSetter) {
				config.SetStateServingInfo(servingInfo)
			}); err != nil {
				return err
			}
			agentConfig = a.CurrentConfig()
		}
		st, m, err := openState(agentConfig)
		if err != nil {
			return err
		}
		if err := st.SetStateServingInfo(servingInfo); err != nil {
			st.Close()
			return fmt.Errorf("cannot set state serving info: %v", err)
		}
		st.Close()
		addrs = m.Addresses()
		shouldInitiateMongoServer = true
	}

	// ensureMongoServer installs/upgrades the upstart config as necessary.
	if err := ensureMongoServer(
		agentConfig.DataDir(),
		namespace,
		servingInfo,
	); err != nil {
		return err
	}
	if !shouldInitiateMongoServer {
		return nil
	}

	// Initiate the replicaset for upgraded environments.
	//
	// TODO(axw) remove this when we no longer need
	// to upgrade from pre-HA-capable environments.
	stateInfo, ok := agentConfig.StateInfo()
	if !ok {
		return fmt.Errorf("state worker was started with no state serving info")
	}
	dialInfo, err := state.DialInfo(stateInfo, state.DefaultDialOpts())
	if err != nil {
		return err
	}
	peerAddr := mongo.SelectPeerAddress(addrs)
	if peerAddr == "" {
		return fmt.Errorf("no appropriate peer address found in %q", addrs)
	}
	return maybeInitiateMongoServer(peergrouper.InitiateMongoParams{
		DialInfo:       dialInfo,
		MemberHostPort: net.JoinHostPort(peerAddr, fmt.Sprint(servingInfo.StatePort)),
		User:           stateInfo.Tag,
		Password:       stateInfo.Password,
	})
}