Golang Manifest.Write方法代碼示例

// SetPod writes a pod manifest into the consul key-value store.
func (c consulStore) SetPod(podPrefix PodPrefix, nodename types.NodeName, manifest manifest.Manifest) (time.Duration, error) {
	buf := bytes.Buffer{}
	err := manifest.Write(&buf)
	if err != nil {
		return 0, err
	}

	key, err := podPath(podPrefix, nodename, manifest.ID())
	if err != nil {
		return 0, err
	}
	keyPair := &api.KVPair{
		Key:   key,
		Value: buf.Bytes(),
	}

	writeMeta, err := c.client.KV().Put(keyPair, nil)
	var retDur time.Duration
	if writeMeta != nil {
		retDur = writeMeta.RequestTime
	}
	if err != nil {
		return retDur, consulutil.NewKVError("put", key, err)
	}
	return retDur, nil
}

func (pod *Pod) WriteCurrentManifest(manifest manifest.Manifest) (string, error) {
	// write the old manifest to a temporary location in case a launch fails.
	tmpDir, err := ioutil.TempDir("", "manifests")
	if err != nil {
		return "", util.Errorf("could not create a tempdir to write old manifest: %s", err)
	}
	lastManifest := filepath.Join(tmpDir, "last_manifest.yaml")

	if _, err := os.Stat(pod.currentPodManifestPath()); err == nil {
		podManifestURL, err := url.Parse(pod.currentPodManifestPath())
		if err != nil {
			return "", util.Errorf("Couldn't parse manifest path '%s' as URL: %s", pod.currentPodManifestPath(), err)
		}

		err = uri.URICopy(podManifestURL, lastManifest)
		if err != nil && !os.IsNotExist(err) {
			return "", err
		}
	}

	f, err := os.OpenFile(pod.currentPodManifestPath(), os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
	if err != nil {
		pod.logError(err, "Unable to open current manifest file")
		err = pod.revertCurrentManifest(lastManifest)
		if err != nil {
			pod.logError(err, "Couldn't replace old manifest as current")
		}
		return "", err
	}
	defer f.Close()

	err = manifest.Write(f)
	if err != nil {
		pod.logError(err, "Unable to write current manifest file")
		err = pod.revertCurrentManifest(lastManifest)
		if err != nil {
			pod.logError(err, "Couldn't replace old manifest as current")
		}
		return "", err
	}

	uid, gid, err := user.IDs(manifest.RunAsUser())
	if err != nil {
		pod.logError(err, "Unable to find pod UID/GID")
		// the write was still successful so we are not going to revert
		return "", err
	}
	err = f.Chown(uid, gid)
	if err != nil {
		pod.logError(err, "Unable to chown current manifest")
		return "", err
	}

	return lastManifest, nil
}

func (h *HookDir) runHooks(dirpath string, hType HookType, pod Pod, podManifest manifest.Manifest, logger logging.Logger) error {
	configFileName, err := podManifest.ConfigFileName()
	if err != nil {
		return err
	}

	// Write manifest to a file so hooks can read it.
	tmpManifestFile, err := ioutil.TempFile("", fmt.Sprintf("%s-manifest.yaml", podManifest.ID()))
	if err != nil {
		logger.WithErrorAndFields(err, logrus.Fields{
			"dir": dirpath,
		}).Warnln("Unable to open manifest file for hooks")
		return err
	}
	defer os.Remove(tmpManifestFile.Name())

	err = podManifest.Write(tmpManifestFile)
	if err != nil {
		logger.WithErrorAndFields(err, logrus.Fields{
			"dir": dirpath,
		}).Warnln("Unable to write manifest file for hooks")
		return err
	}

	hookEnvironment := []string{
		fmt.Sprintf("%s=%s", HOOK_ENV_VAR, path.Base(dirpath)),
		fmt.Sprintf("%s=%s", HOOK_EVENT_ENV_VAR, hType.String()),
		fmt.Sprintf("%s=%s", HOOKED_NODE_ENV_VAR, pod.Node()),
		fmt.Sprintf("%s=%s", HOOKED_POD_ID_ENV_VAR, podManifest.ID()),
		fmt.Sprintf("%s=%s", HOOKED_POD_HOME_ENV_VAR, pod.Home()),
		fmt.Sprintf("%s=%s", HOOKED_POD_MANIFEST_ENV_VAR, tmpManifestFile.Name()),
		fmt.Sprintf("%s=%s", HOOKED_CONFIG_PATH_ENV_VAR, path.Join(pod.ConfigDir(), configFileName)),
		fmt.Sprintf("%s=%s", HOOKED_ENV_PATH_ENV_VAR, pod.EnvDir()),
		fmt.Sprintf("%s=%s", HOOKED_CONFIG_DIR_PATH_ENV_VAR, pod.ConfigDir()),
		fmt.Sprintf("%s=%s", HOOKED_SYSTEM_POD_ROOT_ENV_VAR, h.podRoot),
	}

	return runDirectory(dirpath, hookEnvironment, logger)
}

func writeManifest(workingDir string, manifest manifest.Manifest) (string, error) {
	file, err := os.OpenFile(
		path.Join(workingDir, fmt.Sprintf("%s.yaml", podID())),
		os.O_WRONLY|os.O_CREATE|os.O_TRUNC,
		0644,
	)
	if err != nil {
		return "", err
	}
	defer file.Close()

	err = manifest.Write(file)
	if err != nil {
		return "", err
	}
	return file.Name(), nil
}