storage

package
v0.0.0-...-ec5efcc Latest Latest
Warning

This package is not in the latest version of its module.

Go to latest
Published: Dec 8, 2015 License: Apache-2.0 Imports: 20 Imported by: 0

Documentation

Overview

Package storage contains a Google Cloud Storage client.

This package is experimental and may make backwards-incompatible changes.

Example (Auth)
package main

import (
	"io/ioutil"
	"log"

	"golang.org/x/net/context"
	"golang.org/x/oauth2/google"
	"google.golang.org/cloud"
	"google.golang.org/cloud/storage"
)

func main() {
	// Initialize an authorized context with Google Developers Console
	// JSON key. Read the google package examples to learn more about
	// different authorization flows you can use.
	// http://godoc.org/golang.org/x/oauth2/google
	jsonKey, err := ioutil.ReadFile("/path/to/json/keyfile.json")
	if err != nil {
		log.Fatal(err)
	}
	conf, err := google.JWTConfigFromJSON(
		jsonKey,
		storage.ScopeFullControl,
	)
	if err != nil {
		log.Fatal(err)
	}
	ctx := context.Background()
	client, err := storage.NewClient(ctx, cloud.WithTokenSource(conf.TokenSource(ctx)))
	if err != nil {
		log.Fatal(err)
	}

	// Use the client (see other examples)
	doSomething(client)

	// After using the client, free any resources (e.g. network connections).
	client.Close()
}

func doSomething(c *storage.Client) {}
Output:

Index

Examples

Constants

View Source
const (
	// ScopeFullControl grants permissions to manage your
	// data and permissions in Google Cloud Storage.
	ScopeFullControl = raw.DevstorageFullControlScope

	// ScopeReadOnly grants permissions to
	// view your data in Google Cloud Storage.
	ScopeReadOnly = raw.DevstorageReadOnlyScope

	// ScopeReadWrite grants permissions to manage your
	// data in Google Cloud Storage.
	ScopeReadWrite = raw.DevstorageReadWriteScope
)

Variables

View Source
var (
	ErrBucketNotExist = errors.New("storage: bucket doesn't exist")
	ErrObjectNotExist = errors.New("storage: object doesn't exist")
)

Functions

func SignedURL

func SignedURL(bucket, name string, opts *SignedURLOptions) (string, error)

SignedURL returns a URL for the specified object. Signed URLs allow the users access to a restricted resource for a limited time without having a Google account or signing in. For more information about the signed URLs, see https://cloud.google.com/storage/docs/accesscontrol#Signed-URLs.

Types

type ACLEntity

type ACLEntity string

ACLEntity refers to a user or group. They are sometimes referred to as grantees.

It could be in the form of: "user-<userId>", "user-<email>", "group-<groupId>", "group-<email>", "domain-<domain>" and "project-team-<projectId>".

Or one of the predefined constants: AllUsers, AllAuthenticatedUsers.

const (
	AllUsers              ACLEntity = "allUsers"
	AllAuthenticatedUsers ACLEntity = "allAuthenticatedUsers"
)

type ACLHandle

type ACLHandle struct {
	// contains filtered or unexported fields
}

ACLHandle provides operations on an access control list for a Google Cloud Storage bucket or object.

func (*ACLHandle) Delete

func (a *ACLHandle) Delete(ctx context.Context, entity ACLEntity) error

Delete permanently deletes the ACL entry for the given entity.

func (*ACLHandle) List

func (a *ACLHandle) List(ctx context.Context) ([]ACLRule, error)

List retrieves ACL entries.

func (*ACLHandle) Set

func (a *ACLHandle) Set(ctx context.Context, entity ACLEntity, role ACLRole) error

Set sets the permission level for the given entity.

type ACLRole

type ACLRole string

ACLRole is the level of access to grant.

const (
	RoleOwner  ACLRole = "OWNER"
	RoleReader ACLRole = "READER"
)

type ACLRule

type ACLRule struct {
	Entity ACLEntity
	Role   ACLRole
}

ACLRule represents a grant for a role to an entity (user, group or team) for a Google Cloud Storage object or bucket.

type BucketAttrs

type BucketAttrs struct {
	// Name is the name of the bucket.
	Name string

	// ACL is the list of access control rules on the bucket.
	ACL []ACLRule

	// DefaultObjectACL is the list of access controls to
	// apply to new objects when no object ACL is provided.
	DefaultObjectACL []ACLRule

	// Location is the location of the bucket. It defaults to "US".
	Location string

	// Metageneration is the metadata generation of the bucket.
	Metageneration int64

	// StorageClass is the storage class of the bucket. This defines
	// how objects in the bucket are stored and determines the SLA
	// and the cost of storage. Typical values are "STANDARD" and
	// "DURABLE_REDUCED_AVAILABILITY". Defaults to "STANDARD".
	StorageClass string

	// Created is the creation time of the bucket.
	Created time.Time
}

BucketAttrs represents the metadata for a Google Cloud Storage bucket.

type BucketHandle

type BucketHandle struct {
	// contains filtered or unexported fields
}

BucketHandle provides operations on a Google Cloud Storage bucket. Use Client.Bucket to get a handle.

func (*BucketHandle) ACL

func (c *BucketHandle) ACL() *ACLHandle

ACL returns an ACLHandle, which provides access to the bucket's access control list. This controls who can list, create or overwrite the objects in a bucket. This call does not perform any network operations.

func (*BucketHandle) Attrs

func (b *BucketHandle) Attrs(ctx context.Context) (*BucketAttrs, error)

Attrs returns the metadata for the bucket.

func (*BucketHandle) DefaultObjectACL

func (c *BucketHandle) DefaultObjectACL() *ACLHandle

DefaultObjectACL returns an ACLHandle, which provides access to the bucket's default object ACLs. These ACLs are applied to newly created objects in this bucket that do not have a defined ACL. This call does not perform any network operations.

func (*BucketHandle) List

func (b *BucketHandle) List(ctx context.Context, q *Query) (*ObjectList, error)

List lists objects from the bucket. You can specify a query to filter the results. If q is nil, no filtering is applied.

func (*BucketHandle) Object

func (b *BucketHandle) Object(name string) *ObjectHandle

Object returns an ObjectHandle, which provides operations on the named object. This call does not perform any network operations.

type Client

type Client struct {
	// contains filtered or unexported fields
}

Client is a client for interacting with Google Cloud Storage.

func NewClient

func NewClient(ctx context.Context, opts ...cloud.ClientOption) (*Client, error)

NewClient creates a new Google Cloud Storage client. The default scope is ScopeFullControl. To use a different scope, like ScopeReadOnly, use cloud.WithScopes.

func (*Client) Bucket

func (c *Client) Bucket(name string) *BucketHandle

Bucket returns a BucketHandle, which provides operations on the named bucket. This call does not perform any network operations.

func (*Client) Close

func (c *Client) Close() error

Close closes the Client.

func (*Client) CopyObject

func (c *Client) CopyObject(ctx context.Context, srcBucket, srcName string, destBucket, destName string, attrs *ObjectAttrs) (*ObjectAttrs, error)

CopyObject copies the source object to the destination. The copied object's attributes are overwritten by attrs if non-nil.

type ObjectAttrs

type ObjectAttrs struct {
	// Bucket is the name of the bucket containing this GCS object.
	// This field is read-only.
	Bucket string

	// Name is the name of the object within the bucket.
	Name string

	// ContentType is the MIME type of the object's content.
	ContentType string

	// ContentLanguage is the content language of the object's content.
	ContentLanguage string

	// CacheControl is the Cache-Control header to be sent in the response
	// headers when serving the object data.
	CacheControl string

	// ACL is the list of access control rules for the object.
	ACL []ACLRule

	// Owner is the owner of the object. This field is read-only.
	//
	// If non-zero, it is in the form of "user-<userId>".
	Owner string

	// Size is the length of the object's content. This field is read-only.
	Size int64

	// ContentEncoding is the encoding of the object's content.
	ContentEncoding string

	// ContentDisposition is the optional Content-Disposition header of the object
	// sent in the response headers.
	ContentDisposition string

	// MD5 is the MD5 hash of the object's content. This field is read-only.
	MD5 []byte

	// CRC32C is the CRC32 checksum of the object's content using
	// the Castagnoli93 polynomial. This field is read-only.
	CRC32C uint32

	// MediaLink is an URL to the object's content. This field is read-only.
	MediaLink string

	// Metadata represents user-provided metadata, in key/value pairs.
	// It can be nil if no metadata is provided.
	Metadata map[string]string

	// Generation is the generation number of the object's content.
	// This field is read-only.
	Generation int64

	// MetaGeneration is the version of the metadata for this
	// object at this generation. This field is used for preconditions
	// and for detecting changes in metadata. A metageneration number
	// is only meaningful in the context of a particular generation
	// of a particular object. This field is read-only.
	MetaGeneration int64

	// StorageClass is the storage class of the bucket.
	// This value defines how objects in the bucket are stored and
	// determines the SLA and the cost of storage. Typical values are
	// "STANDARD" and "DURABLE_REDUCED_AVAILABILITY".
	// It defaults to "STANDARD". This field is read-only.
	StorageClass string

	// Deleted is the time the object was deleted.
	// If not deleted, it is the zero value. This field is read-only.
	Deleted time.Time

	// Updated is the creation or modification time of the object.
	// For buckets with versioning enabled, changing an object's
	// metadata does not change this property. This field is read-only.
	Updated time.Time
}

ObjectAttrs represents the metadata for a Google Cloud Storage (GCS) object.

type ObjectHandle

type ObjectHandle struct {
	// contains filtered or unexported fields
}

ObjectHandle provides operations on an object in a Google Cloud Storage bucket. Use BucketHandle.Object to get a handle.

func (*ObjectHandle) ACL

func (o *ObjectHandle) ACL() *ACLHandle

ACL provides access to the object's access control list. This controls who can read and write this object. This call does not perform any network operations.

func (*ObjectHandle) Attrs

func (o *ObjectHandle) Attrs(ctx context.Context) (*ObjectAttrs, error)

Attrs returns meta information about the object. ErrObjectNotExist will be returned if the object is not found.

func (*ObjectHandle) Delete

func (o *ObjectHandle) Delete(ctx context.Context) error

Delete deletes the single specified object.

func (*ObjectHandle) NewReader

func (o *ObjectHandle) NewReader(ctx context.Context) (io.ReadCloser, error)

NewReader creates a new io.ReadCloser to read the contents of the object. ErrObjectNotExist will be returned if the object is not found.

func (*ObjectHandle) NewWriter

func (o *ObjectHandle) NewWriter(ctx context.Context) *Writer

NewWriter returns a storage Writer that writes to the GCS object identified by the specified name. If such an object doesn't exist, it creates one. Attributes can be set on the object by modifying the returned Writer's ObjectAttrs field before the first call to Write. The name parameter to this function is ignored if the Name field of the ObjectAttrs field is set to a non-empty string.

It is the caller's responsibility to call Close when writing is done.

The object is not available and any previous object with the same name is not replaced on Cloud Storage until Close is called.

func (*ObjectHandle) Update

func (o *ObjectHandle) Update(ctx context.Context, attrs ObjectAttrs) (*ObjectAttrs, error)

Update updates an object with the provided attributes. All zero-value attributes are ignored. ErrObjectNotExist will be returned if the object is not found.

type ObjectList

type ObjectList struct {
	// Results represent a list of object results.
	Results []*ObjectAttrs

	// Next is the continuation query to retrieve more
	// results with the same filtering criteria. If there
	// are no more results to retrieve, it is nil.
	Next *Query

	// Prefixes represents prefixes of objects
	// matching-but-not-listed up to and including
	// the requested delimiter.
	Prefixes []string
}

ObjectList represents a list of objects returned from a bucket List call.

type Query

type Query struct {
	// Delimiter returns results in a directory-like fashion.
	// Results will contain only objects whose names, aside from the
	// prefix, do not contain delimiter. Objects whose names,
	// aside from the prefix, contain delimiter will have their name,
	// truncated after the delimiter, returned in prefixes.
	// Duplicate prefixes are omitted.
	// Optional.
	Delimiter string

	// Prefix is the prefix filter to query objects
	// whose names begin with this prefix.
	// Optional.
	Prefix string

	// Versions indicates whether multiple versions of the same
	// object will be included in the results.
	Versions bool

	// Cursor is a previously-returned page token
	// representing part of the larger set of results to view.
	// Optional.
	Cursor string

	// MaxResults is the maximum number of items plus prefixes
	// to return. As duplicate prefixes are omitted,
	// fewer total results may be returned than requested.
	// The default page limit is used if it is negative or zero.
	MaxResults int
}

Query represents a query to filter objects from a bucket.

type SignedURLOptions

type SignedURLOptions struct {
	// GoogleAccessID represents the authorizer of the signed URL generation.
	// It is typically the Google service account client email address from
	// the Google Developers Console in the form of "xxx@developer.gserviceaccount.com".
	// Required.
	GoogleAccessID string

	// PrivateKey is the Google service account private key. It is obtainable
	// from the Google Developers Console.
	// At https://console.developers.google.com/project/<your-project-id>/apiui/credential,
	// create a service account client ID or reuse one of your existing service account
	// credentials. Click on the "Generate new P12 key" to generate and download
	// a new private key. Once you download the P12 file, use the following command
	// to convert it into a PEM file.
	//
	//    $ openssl pkcs12 -in key.p12 -passin pass:notasecret -out key.pem -nodes
	//
	// Provide the contents of the PEM file as a byte slice.
	// Required.
	PrivateKey []byte

	// Method is the HTTP method to be used with the signed URL.
	// Signed URLs can be used with GET, HEAD, PUT, and DELETE requests.
	// Required.
	Method string

	// Expires is the expiration time on the signed URL. It must be
	// a datetime in the future.
	// Required.
	Expires time.Time

	// ContentType is the content type header the client must provide
	// to use the generated signed URL.
	// Optional.
	ContentType string

	// Headers is a list of extention headers the client must provide
	// in order to use the generated signed URL.
	// Optional.
	Headers []string

	// MD5 is the base64 encoded MD5 checksum of the file.
	// If provided, the client should provide the exact value on the request
	// header in order to use the signed URL.
	// Optional.
	MD5 []byte
}

SignedURLOptions allows you to restrict the access to the signed URL.

type Writer

type Writer struct {
	// ObjectAttrs are optional attributes to set on the object. Any attributes
	// must be initialized before the first Write call. Nil or zero-valued
	// attributes are ignored.
	ObjectAttrs
	// contains filtered or unexported fields
}

A Writer writes a Cloud Storage object.

func (*Writer) Attrs

func (w *Writer) Attrs() *ObjectAttrs

ObjectAttrs returns metadata about a successfully-written object. It's only valid to call it after Close returns nil.

func (*Writer) Close

func (w *Writer) Close() error

Close completes the write operation and flushes any buffered data. If Close doesn't return an error, metadata about the written object can be retrieved by calling Object.

func (*Writer) CloseWithError

func (w *Writer) CloseWithError(err error) error

CloseWithError aborts the write operation with the provided error. CloseWithError always returns nil.

func (*Writer) Write

func (w *Writer) Write(p []byte) (n int, err error)

Write appends to w.

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL