Golang Environ.SetConfig方法代码示例

func (u *Upgrader) run() error {
	// Let the state know the version that is currently running.
	currentTools, err := tools.ReadTools(u.dataDir, version.Current)
	if err != nil {
		// Don't abort everything because we can't find the tools directory.
		// The problem should sort itself out as we will immediately
		// download some more tools and upgrade.
		log.Warningf("upgrader cannot read current tools: %v", err)
		currentTools = &tools.Tools{
			Binary: version.Current,
		}
	}
	err = u.agentState.SetAgentTools(currentTools)
	if err != nil {
		return err
	}

	// TODO(fwereade): this whole package should be ignorant of environs,
	// so it shouldn't be watching environ config (and it shouldn't be
	// looking in storage): we should be able to find out what to download
	// from state, exactly as we do for charms.
	w := u.st.WatchEnvironConfig()
	defer watcher.Stop(w, &u.tomb)

	// Rather than using worker.WaitForEnviron, invalid environments are
	// managed explicitly so that all configuration changes are observed
	// by the loop below.
	var environ environs.Environ

	// TODO(rog) retry downloads when they fail.
	var (
		download      *downloader.Download
		downloadTools *tools.Tools
		downloadDone  <-chan downloader.Status
	)
	// If we're killed early on (probably as a result of some other
	// task dying) we allow ourselves some time to try to connect to
	// the state and download a new version. We return to normal
	// undelayed behaviour when:
	// 1) We find there's no upgrade to do.
	// 2) A download fails.
	tomb := delayedTomb(&u.tomb, upgraderKillDelay)
	noDelay := func() {
		if tomb != &u.tomb {
			tomb.Kill(nil)
			tomb = &u.tomb
		}
	}
	for {
		// We wait for the tools to change while we're downloading
		// so that if something goes wrong (for instance a bad URL
		// hangs up) another change to the proposed tools can
		// potentially fix things.
		select {
		case cfg, ok := <-w.Changes():
			if !ok {
				return watcher.MustErr(w)
			}
			var err error
			if environ == nil {
				environ, err = environs.New(cfg)
				if err != nil {
					log.Errorf("upgrader loaded invalid initial environment configuration: %v", err)
					break
				}
			} else {
				err = environ.SetConfig(cfg)
				if err != nil {
					log.Warningf("upgrader loaded invalid environment configuration: %v", err)
					// continue on, because the version number is still significant.
				}
			}
			proposed, ok := cfg.AgentVersion()
			if !ok {
				// This shouldn't be possible; but if it happens it's no reason
				// to kill this task. Just wait for the config to change again.
				continue
			}
			if download != nil {
				// There's a download in progress, stop it if we need to.
				if downloadTools.Number == proposed {
					// We are already downloading the requested tools.
					break
				}
				// Tools changed. We need to stop and restart.
				download.Stop()
				download, downloadTools, downloadDone = nil, nil, nil
			}
			// TODO: major version upgrades.
			if proposed.Major != version.Current.Major {
				log.Errorf("major version upgrades are not supported yet")
				noDelay()
				break
			}
			if proposed == version.Current.Number {
				noDelay()
				break
			}
			required := version.Binary{
				Number: proposed,
//.........这里部分代码省略.........

func (u *Upgrader) run() error {
	// Let the state know the version that is currently running.
	currentTools, err := environs.ReadTools(u.dataDir, version.Current)
	if err != nil {
		// Don't abort everything because we can't find the tools directory.
		// The problem should sort itself out as we will immediately
		// download some more tools and upgrade.
		log.Printf("cmd/jujud: upgrader cannot read current tools: %v", err)
		currentTools = &state.Tools{
			Binary: version.Current,
		}
	}
	err = u.agentState.SetAgentTools(currentTools)
	if err != nil {
		return err
	}

	w := u.st.WatchEnvironConfig()
	defer watcher.Stop(w, &u.tomb)

	// Rather than using worker.WaitForEnviron, invalid environments are
	// managed explicitly so that all configuration changes are observed
	// by the loop below.
	var environ environs.Environ

	// TODO(rog) retry downloads when they fail.
	var (
		download      *downloader.Download
		downloadTools *state.Tools
		downloadDone  <-chan downloader.Status
	)
	// If we're killed early on (probably as a result of some other
	// task dying) we allow ourselves some time to try to connect to
	// the state and download a new version. We return to normal
	// undelayed behaviour when:
	// 1) We find there's no upgrade to do.
	// 2) A download fails.
	tomb := delayedTomb(&u.tomb, upgraderKillDelay)
	noDelay := func() {
		if tomb != &u.tomb {
			tomb.Kill(nil)
			tomb = &u.tomb
		}
	}
	for {
		// We wait for the tools to change while we're downloading
		// so that if something goes wrong (for instance a bad URL
		// hangs up) another change to the proposed tools can
		// potentially fix things.
		select {
		case cfg, ok := <-w.Changes():
			if !ok {
				return watcher.MustErr(w)
			}
			var err error
			if environ == nil {
				environ, err = environs.New(cfg)
				if err != nil {
					log.Printf("cmd/jujud: upgrader loaded invalid initial environment configuration: %v", err)
					break
				}
			} else {
				err = environ.SetConfig(cfg)
				if err != nil {
					log.Printf("cmd/jujud: upgrader loaded invalid environment configuration: %v", err)
					// continue on, because the version number is still significant.
				}
			}
			vers := cfg.AgentVersion()
			if download != nil {
				// There's a download in progress, stop it if we need to.
				if vers == downloadTools.Number {
					// We are already downloading the requested tools.
					break
				}
				// Tools changed. We need to stop and restart.
				download.Stop()
				download, downloadTools, downloadDone = nil, nil, nil
			}
			// Ignore the proposed tools if we're already running the
			// proposed version.
			if vers == version.Current.Number {
				noDelay()
				break
			}
			binary := version.Current
			binary.Number = vers

			if tools, err := environs.ReadTools(u.dataDir, binary); err == nil {
				// The tools have already been downloaded, so use them.
				return u.upgradeReady(currentTools, tools)
			}
			flags := environs.CompatVersion
			if cfg.Development() {
				flags |= environs.DevVersion
			}
			tools, err := environs.FindTools(environ, binary, flags)
			if err != nil {
				log.Printf("cmd/jujud: upgrader error finding tools for %v: %v", binary, err)
				noDelay()
//.........这里部分代码省略.........