Golang storage.ListObjects函数代码示例

func listBucket(ctx context.Context, bucketName, folder string) ([]string, []string, error) {
	cloudContext, err := getCloudContext(ctx)
	if err != nil {
		return nil, nil, err
	}

	var files, folders []string

	query := &storage.Query{
		Delimiter: "/",
		Prefix:    folder,
	}
	// objs is *storage.Objects
	objs, err := storage.ListObjects(cloudContext, bucketName, query)
	if err != nil {
		return nil, nil, err
	}

	for _, subfolder := range objs.Prefixes {
		folders = append(folders, subfolder[len(folder):])
	}

	for _, obj := range objs.Results {
		files = append(files, obj.Name)
	}

	return files, folders, nil
}

func handleList(res http.ResponseWriter, req *http.Request) {
	ctx := appengine.NewContext(req)
	cctx := getCloudContext(ctx)

	query := &storage.Query{
		Prefix: prefix,
	}
	objs, err := storage.ListObjects(cctx, bucket, query)
	if err != nil {
		http.Error(res, err.Error(), 500)
		return
	}
	t, err := template.New("").Parse(`<li><a href="/get?f={{.}}">{{.}}</a></li>`)
	if err != nil {
		http.Error(res, err.Error(), 500)
		return
	}
	res.Header().Set("Content-Type", "text/html")
	io.WriteString(res, `<form action="put" method="POST" enctype="multipart/form-data"><input name="f" type="file"><input type="submit"></form> <ul>`)
	for _, obj := range objs.Results {
		err := t.Execute(res, obj.Name[len(prefix):])
		if err != nil {
			http.Error(res, err.Error(), 500)
			return
		}
	}
	io.WriteString(res, `</ul>`)
}

// listAll recursively lists all names of objects stored at "prefix" and its subpaths.
func (d *driver) listAll(context context.Context, prefix string) ([]string, error) {
	list := make([]string, 0, 64)
	query := &storage.Query{}
	query.Prefix = prefix
	query.Versions = false
	for {
		objects, err := storage.ListObjects(d.context(context), d.bucket, query)
		if err != nil {
			return nil, err
		}
		for _, obj := range objects.Results {
			// GCS does not guarantee strong consistency between
			// DELETE and LIST operationsCheck that the object is not deleted,
			// so filter out any objects with a non-zero time-deleted
			if obj.Deleted.IsZero() {
				list = append(list, obj.Name)
			}
		}
		query = objects.Next
		if query == nil {
			break
		}
	}
	return list, nil
}

// RemoveBackup implements BackupStorage.
func (bs *GCSBackupStorage) RemoveBackup(dir, name string) error {
	authCtx, err := bs.authContext()
	if err != nil {
		return err
	}

	// Find all objects with the right prefix.
	query := &storage.Query{
		Prefix: objName(dir, name, "" /* include trailing slash */),
	}

	// Loop in case results are returned in multiple batches.
	for query != nil {
		objs, err := storage.ListObjects(authCtx, *bucket, query)
		if err != nil {
			return err
		}

		// Delete all the found objects.
		for _, obj := range objs.Results {
			if err := storage.DeleteObject(authCtx, *bucket, obj.Name); err != nil {
				return fmt.Errorf("unable to delete %q from bucket %q: %v", obj.Name, *bucket, err)
			}
		}

		query = objs.Next
	}

	return nil
}

func browse(res http.ResponseWriter, req *http.Request) {
	ctx := appengine.NewContext(req)
	session := getSession(ctx, req)

	// if no bucket has been chosen
	if session.Bucket == "" {
		http.Redirect(res, req, "/", 302)
		return
	}

	folder := strings.SplitN(req.URL.Path, "/", 3)[2]

	cctx, err := getCloudContext(ctx)
	if err != nil {
		http.Error(res, err.Error(), 500)
		return
	}
	objects, err := storage.ListObjects(cctx, session.Bucket, nil)
	if err != nil {
		http.Error(res, err.Error(), 401)
		return
	}
	model := &browseModel{
		Bucket:  session.Bucket,
		Folder:  folder,
		Objects: objects.Results,
	}

	err = tpls.ExecuteTemplate(res, "browse.html", model)
	if err != nil {
		http.Error(res, err.Error(), 500)
	}
}

func ExampleListObjects() {
	ctx := Example_auth()

	var query *storage.Query
	for {
		// If you are using this package on App Engine Managed VMs runtime,
		// you can init a bucket client with your app's default bucket name.
		// See http://godoc.org/google.golang.org/appengine/file#DefaultBucketName.
		objects, err := storage.ListObjects(ctx, "bucketname", query)
		if err != nil {
			log.Fatal(err)
		}
		for _, obj := range objects.Results {
			log.Printf("object name: %s, size: %v", obj.Name, obj.Size)
		}
		// if there are more results, objects.Next
		// will be non-nil.
		query = objects.Next
		if query == nil {
			break
		}
	}

	log.Println("paginated through all object items in the bucket you specified.")
}

func ExampleDeleteObject() {
	// To delete multiple objects in a bucket, first ListObjects then delete them.
	ctx := Example_auth()

	// If you are using this package on App Engine Managed VMs runtime,
	// you can init a bucket client with your app's default bucket name.
	// See http://godoc.org/google.golang.org/appengine/file#DefaultBucketName.
	const bucket = "bucketname"

	var query *storage.Query // Set up query as desired.
	for {
		objects, err := storage.ListObjects(ctx, bucket, query)
		if err != nil {
			log.Fatal(err)
		}
		for _, obj := range objects.Results {
			log.Printf("deleting object name: %q, size: %v", obj.Name, obj.Size)
			if err := storage.DeleteObject(ctx, bucket, obj.Name); err != nil {
				log.Fatalf("unable to delete %q: %v", obj.Name, err)
			}
		}
		// if there are more results, objects.Next will be non-nil.
		query = objects.Next
		if query == nil {
			break
		}
	}

	log.Println("deleted all object items in the bucket you specified.")
}

// List returns a list of the objects that are direct descendants of the
//given path.
func (d *driver) List(context ctx.Context, path string) ([]string, error) {
	var query *storage.Query
	query = &storage.Query{}
	query.Delimiter = "/"
	query.Prefix = d.pathToDirKey(path)
	list := make([]string, 0, 64)
	for {
		objects, err := storage.ListObjects(d.context(context), d.bucket, query)
		if err != nil {
			return nil, err
		}
		for _, object := range objects.Results {
			// GCS does not guarantee strong consistency between
			// DELETE and LIST operationsCheck that the object is not deleted,
			// so filter out any objects with a non-zero time-deleted
			if object.Deleted.IsZero() {
				name := object.Name
				// Ignore objects with names that end with '#' (these are uploaded parts)
				if name[len(name)-1] != '#' {
					name = d.keyToPath(name)
					list = append(list, name)
				}
			}
		}
		for _, subpath := range objects.Prefixes {
			subpath = d.keyToPath(subpath)
			list = append(list, subpath)
		}
		query = objects.Next
		if query == nil {
			break
		}
	}
	return list, nil
}

func storageListObjects(context context.Context, bucket string, q *storage.Query) (*storage.Objects, error) {
	var objs *storage.Objects
	err := retry(5, func() error {
		var err error
		objs, err = storage.ListObjects(context, bucket, q)
		return err
	})
	return objs, err
}

func handleList(res http.ResponseWriter, req *http.Request) {
	ctx := appengine.NewContext(req)
	cctx := getCloudContext(ctx)

	var query *storage.Query
	objs, err := storage.ListObjects(cctx, bucketName, query)
	if err != nil {
		http.Error(res, err.Error(), 500)
		return
	}
	for _, obj := range objs.Results {
		fmt.Fprintln(res, obj.Name)
	}
}

// ListBackups implements BackupStorage.
func (bs *GCSBackupStorage) ListBackups(dir string) ([]backupstorage.BackupHandle, error) {
	authCtx, err := bs.authContext()
	if err != nil {
		return nil, err
	}

	// List prefixes that begin with dir (i.e. list subdirs).
	var subdirs []string
	searchPrefix := objName(dir, "" /* include trailing slash */)
	query := &storage.Query{
		Delimiter: "/",
		Prefix:    searchPrefix,
	}

	// Loop in case results are returned in multiple batches.
	for query != nil {
		objs, err := storage.ListObjects(authCtx, *bucket, query)
		if err != nil {
			return nil, err
		}

		// Each returned prefix is a subdir.
		// Strip parent dir from full path.
		for _, prefix := range objs.Prefixes {
			subdir := strings.TrimPrefix(prefix, searchPrefix)
			subdir = strings.TrimSuffix(subdir, "/")
			subdirs = append(subdirs, subdir)
		}

		query = objs.Next
	}

	// Backups must be returned in order, oldest first.
	sort.Strings(subdirs)

	result := make([]backupstorage.BackupHandle, 0, len(subdirs))
	for _, subdir := range subdirs {
		result = append(result, &GCSBackupHandle{
			authCtx:  authCtx,
			bs:       bs,
			dir:      dir,
			name:     subdir,
			readOnly: true,
		})
	}
	return result, nil
}

func handleList(res http.ResponseWriter, req *http.Request) {
	cctx, err := getCloudContext(req)
	if err != nil {
		http.Error(res, "ERROR GETTING CCTX: "+err.Error(), 500)
		return
	}

	var query *storage.Query
	objs, err := storage.ListObjects(cctx, gcsBucket, query)
	if err != nil {
		http.Error(res, err.Error(), 500)
		return
	}
	for _, obj := range objs.Results {
		fmt.Fprintln(res, obj.Name)
	}
}

// listBucket lists the contents of a bucket in Google Cloud Storage.
func (d *demo) listBucket() {
	io.WriteString(d.w, "\nListbucket result:\n")

	query := &storage.Query{Prefix: "foo"}
	for query != nil {
		objs, err := storage.ListObjects(d.ctx, bucket, query)
		if err != nil {
			d.errorf("listBucket: unable to list bucket %q: %v", bucket, err)
			return
		}
		query = objs.Next

		for _, obj := range objs.Results {
			d.dumpStats(obj)
		}
	}
}

func listFiles(cctx context.Context, bucket, path string) ([]string, []string, error) {
	q := &storage.Query{
		Delimiter: delimiter,
		Prefix:    path,
	}
	objs, err := storage.ListObjects(cctx, bucket, q)
	if err != nil {
		return nil, nil, err
	}
	subfolders := []string{}
	for _, v := range objs.Prefixes {
		subfolders = append(subfolders, strings.TrimPrefix(v, path))
	}
	files := []string{}
	for _, v := range objs.Results {
		files = append(files, v.Name)
	}
	return files, subfolders, nil
}

func (bs *GCSBlobStore) ListBlobs() ([]string, error) {
	ctx := bs.newAuthedContext(context.TODO())
	ret := make([]string, 0)

	q := &storage.Query{}
	for q != nil {
		res, err := storage.ListObjects(ctx, bs.bucketName, q)
		if err != nil {
			return nil, err
		}
		for _, o := range res.Results {
			blobpath := o.Name
			ret = append(ret, blobpath)
		}
		q = res.Next
	}

	return ret, nil
}