Golang StorageDriver.Stat方法代码示例

// newFileWriter returns a prepared fileWriter for the driver and path. This
// could be considered similar to an "open" call on a regular filesystem.
func newFileWriter(driver storagedriver.StorageDriver, path string) (*bufferedFileWriter, error) {
	fw := fileWriter{
		driver: driver,
		path:   path,
	}

	if fi, err := driver.Stat(path); err != nil {
		switch err := err.(type) {
		case storagedriver.PathNotFoundError:
			// ignore, offset is zero
		default:
			return nil, err
		}
	} else {
		if fi.IsDir() {
			return nil, fmt.Errorf("cannot write to a directory")
		}

		fw.size = fi.Size()
	}

	buffered := bufferedFileWriter{
		fileWriter: fw,
	}
	buffered.bw = bufio.NewWriterSize(&buffered.fileWriter, fileWriterBufferSize)

	return &buffered, nil
}

// WalkWithChildrenFilter traverses a filesystem defined within driver,
// starting from the given path, calling f on each file. Given filter will be
// called on a list of directory children before being recursively processed.
func WalkWithChildrenFilter(ctx context.Context, driver storageDriver.StorageDriver, from string, filter WalkChildrenFilter, f WalkFn) error {
	children, err := driver.List(ctx, from)
	if err != nil {
		return err
	}
	filter(children)
	for _, child := range children {
		// TODO(stevvooe): Calling driver.Stat for every entry is quite
		// expensive when running against backends with a slow Stat
		// implementation, such as s3. This is very likely a serious
		// performance bottleneck.
		fileInfo, err := driver.Stat(ctx, child)
		if err != nil {
			return err
		}
		err = f(fileInfo)
		skipDir := (err == ErrSkipDir)
		if err != nil && !skipDir {
			return err
		}

		if fileInfo.IsDir() && !skipDir {
			if err := WalkWithChildrenFilter(ctx, driver, child, filter, f); err != nil {
				return err
			}
		}
	}
	return nil
}

// newFileReader initializes a file reader for the remote file. The read takes
// on the offset and size at the time the reader is created. If the underlying
// file changes, one must create a new fileReader.
func newFileReader(driver storagedriver.StorageDriver, path string) (*fileReader, error) {
	rd := &fileReader{
		driver: driver,
		path:   path,
	}

	// Grab the size of the layer file, ensuring existence.
	if fi, err := driver.Stat(path); err != nil {
		switch err := err.(type) {
		case storagedriver.PathNotFoundError:
			// NOTE(stevvooe): We really don't care if the file is not
			// actually present for the reader. If the caller needs to know
			// whether or not the file exists, they should issue a stat call
			// on the path. There is still no guarantee, since the file may be
			// gone by the time the reader is created. The only correct
			// behavior is to return a reader that immediately returns EOF.
		default:
			// Any other error we want propagated up the stack.
			return nil, err
		}
	} else {
		if fi.IsDir() {
			return nil, fmt.Errorf("cannot read a directory")
		}

		// Fill in file information
		rd.size = fi.Size()
		rd.modtime = fi.ModTime()
	}

	return rd, nil
}

// Exists provides a utility method to test whether or not a path exists in
// the given driver.
func exists(ctx context.Context, drv driver.StorageDriver, path string) (bool, error) {
	if _, err := drv.Stat(ctx, path); err != nil {
		switch err := err.(type) {
		case driver.PathNotFoundError:
			return false, nil
		default:
			return false, err
		}
	}

	return true, nil
}

// exists provides a utility method to test whether or not
func exists(driver storagedriver.StorageDriver, path string) (bool, error) {
	if _, err := driver.Stat(path); err != nil {
		switch err := err.(type) {
		case storagedriver.PathNotFoundError:
			return false, nil
		default:
			return false, err
		}
	}

	return true, nil
}

// Walk traverses a filesystem defined within driver, starting
// from the given path, calling f on each file
func Walk(driver storageDriver.StorageDriver, from string, f WalkFn) error {
	children, err := driver.List(from)
	if err != nil {
		return err
	}
	for _, child := range children {
		fileInfo, err := driver.Stat(child)
		if err != nil {
			return err
		}
		err = f(fileInfo)
		skipDir := (err == ErrSkipDir)
		if err != nil && !skipDir {
			return err
		}

		if fileInfo.IsDir() && !skipDir {
			Walk(driver, child, f)
		}
	}
	return nil
}

// newFileWriter returns a prepared fileWriter for the driver and path. This
// could be considered similar to an "open" call on a regular filesystem.
func newFileWriter(ctx context.Context, driver storagedriver.StorageDriver, path string) (*fileWriter, error) {
	fw := fileWriter{
		driver: driver,
		path:   path,
		ctx:    ctx,
	}

	if fi, err := driver.Stat(ctx, path); err != nil {
		switch err := err.(type) {
		case storagedriver.PathNotFoundError:
			// ignore, offset is zero
		default:
			return nil, err
		}
	} else {
		if fi.IsDir() {
			return nil, fmt.Errorf("cannot write to a directory")
		}

		fw.size = fi.Size()
	}

	return &fw, nil
}

func build(
	conf *Config,
	storageDriver storagedriver.StorageDriver,
	kubeClient *client.Client,
	fs sys.FS,
	env sys.Env,
	builderKey,
	rawGitSha string) error {

	dockerBuilderImagePullPolicy, err := k8s.PullPolicyFromString(conf.DockerBuilderImagePullPolicy)
	if err != nil {
		return err
	}

	slugBuilderImagePullPolicy, err := k8s.PullPolicyFromString(conf.SlugBuilderImagePullPolicy)
	if err != nil {
		return err
	}

	repo := conf.Repository
	gitSha, err := git.NewSha(rawGitSha)
	if err != nil {
		return err
	}

	appName := conf.App()

	repoDir := filepath.Join(conf.GitHome, repo)
	buildDir := filepath.Join(repoDir, "build")

	slugName := fmt.Sprintf("%s:git-%s", appName, gitSha.Short())
	if err := os.MkdirAll(buildDir, os.ModeDir); err != nil {
		return fmt.Errorf("making the build directory %s (%s)", buildDir, err)
	}

	tmpDir, err := ioutil.TempDir(buildDir, "tmp")
	if err != nil {
		return fmt.Errorf("unable to create tmpdir %s (%s)", buildDir, err)
	}
	defer func() {
		if err := os.RemoveAll(tmpDir); err != nil {
			log.Info("unable to remove tmpdir %s (%s)", tmpDir, err)
		}
	}()

	client, err := controller.New(conf.ControllerHost, conf.ControllerPort)
	if err != nil {
		return err
	}

	// Get the application config from the controller, so we can check for a custom buildpack URL
	appConf, err := hooks.GetAppConfig(client, conf.Username, appName)
	if controller.CheckAPICompat(client, err) != nil {
		return err
	}

	log.Debug("got the following config back for app %s: %+v", appName, appConf)
	var buildPackURL string
	if buildPackURLInterface, ok := appConf.Values["BUILDPACK_URL"]; ok {
		if bpStr, ok := buildPackURLInterface.(string); ok {
			log.Debug("found custom buildpack URL %s", bpStr)
			buildPackURL = bpStr
		}
	}

	_, disableCaching := appConf.Values["DEIS_DISABLE_CACHE"]
	slugBuilderInfo := NewSlugBuilderInfo(appName, gitSha.Short(), disableCaching)

	if slugBuilderInfo.DisableCaching() {
		log.Debug("caching disabled for app %s", appName)
		// If cache file exists, delete it
		if _, err := storageDriver.Stat(context.Background(), slugBuilderInfo.CacheKey()); err == nil {
			log.Debug("deleting cache %s for app %s", slugBuilderInfo.CacheKey(), appName)
			if err := storageDriver.Delete(context.Background(), slugBuilderInfo.CacheKey()); err != nil {
				return err
			}
		}
	}

	// build a tarball from the new objects
	appTgz := fmt.Sprintf("%s.tar.gz", appName)
	gitArchiveCmd := repoCmd(repoDir, "git", "archive", "--format=tar.gz", fmt.Sprintf("--output=%s", appTgz), gitSha.Short())
	gitArchiveCmd.Stdout = os.Stdout
	gitArchiveCmd.Stderr = os.Stderr
	if err := run(gitArchiveCmd); err != nil {
		return fmt.Errorf("running %s (%s)", strings.Join(gitArchiveCmd.Args, " "), err)
	}
	absAppTgz := fmt.Sprintf("%s/%s", repoDir, appTgz)

	// untar the archive into the temp dir
	tarCmd := repoCmd(repoDir, "tar", "-xzf", appTgz, "-C", fmt.Sprintf("%s/", tmpDir))
	tarCmd.Stdout = os.Stdout
	tarCmd.Stderr = os.Stderr
	if err := run(tarCmd); err != nil {
		return fmt.Errorf("running %s (%s)", strings.Join(tarCmd.Args, " "), err)
	}

	bType := getBuildTypeForDir(tmpDir)
	usingDockerfile := bType == buildTypeDockerfile

//.........这里部分代码省略.........