cloud

README

Google Cloud for Go

NOTE: This repo exists solely to transition to the new import paths at cloud.google.com/go. It will be removed on September 12, 2016. Only emergency pull requests will be accepted.

To migrate off this repo, change import paths beginning google.golang.org/cloud to cloud.google.com/go, except for the options in the google.golang.org/cloud package itself, which are now at google.golang.org/api/option. See details here.

import "google.golang.org/cloud"

NOTE: These packages are under development, and may occasionally make backwards-incompatible changes.

NOTE: Github repo is a mirror of https://code.googlesource.com/gocloud.

Go packages for Google Cloud Platform services. Supported APIs are:

Google API	Status	Package
Datastore	beta	google.golang.org/cloud/datastore
Storage	beta	google.golang.org/cloud/storage
Pub/Sub	experimental	google.golang.org/cloud/pubsub
Bigtable	stable	google.golang.org/cloud/bigtable
BigQuery	experimental	google.golang.org/cloud/bigquery
Logging	experimental	google.golang.org/cloud/logging

Experimental status: the API is still being actively developed. As a result, it might change in backward-incompatible ways and is not recommended for production use.

Beta status: the API is largely complete, but still has outstanding features and bugs to be addressed. There may be minor backwards-incompatible changes where necessary.

Stable status: the API is mature and ready for production use. We will continue addressing bugs and feature requests.

Documentation and examples are available at https://godoc.org/google.golang.org/cloud

Visit or join the google-api-go-announce group for updates on these packages.

Go Versions Supported

We support the two most recent major versions of Go. If Google App Engine uses an older version, we support that as well. You can see which versions are currently supported by looking at the lines following go: in .travis.yml.

Authorization

By default, each API will use Google Application Default Credentials for authorization credentials used in calling the API endpoints. This will allow your application to run in many environments without requiring explicit configuration.

Manually-configured authorization can be achieved using the golang.org/x/oauth2 package to create an oauth2.TokenSource. This token source can be passed to the NewClient function for the relevant API using a cloud.WithTokenSource option.

Google Cloud Datastore

Google Cloud Datastore (docs) is a fully- managed, schemaless database for storing non-relational data. Cloud Datastore automatically scales with your users and supports ACID transactions, high availability of reads and writes, strong consistency for reads and ancestor queries, and eventual consistency for all other queries.

Follow the activation instructions to use the Google Cloud Datastore API with your project.

First create a datastore.Client to use throughout your application:

client, err := datastore.NewClient(ctx, "my-project-id")
if err != nil {
	log.Fatalln(err)
}

Then use that client to interact with the API:

type Post struct {
	Title       string
	Body        string `datastore:",noindex"`
	PublishedAt time.Time
}
keys := []*datastore.Key{
	datastore.NewKey(ctx, "Post", "post1", 0, nil),
	datastore.NewKey(ctx, "Post", "post2", 0, nil),
}
posts := []*Post{
	{Title: "Post 1", Body: "...", PublishedAt: time.Now()},
	{Title: "Post 2", Body: "...", PublishedAt: time.Now()},
}
if _, err := client.PutMulti(ctx, keys, posts); err != nil {
	log.Fatal(err)
}

Google Cloud Storage

Google Cloud Storage (docs) allows you to store data on Google infrastructure with very high reliability, performance and availability, and can be used to distribute large data objects to users via direct download.

https://godoc.org/google.golang.org/cloud/storage

First create a storage.Client to use throughout your application:

client, err := storage.NewClient(ctx)
if err != nil {
	log.Fatal(err)
}

// Read the object1 from bucket.
rc, err := client.Bucket("bucket").Object("object1").NewReader(ctx)
if err != nil {
	log.Fatal(err)
}
defer rc.Close()
body, err := ioutil.ReadAll(rc)
if err != nil {
	log.Fatal(err)
}

Google Cloud Pub/Sub

Google Cloud Pub/Sub (docs) allows you to connect your services with reliable, many-to-many, asynchronous messaging hosted on Google's infrastructure. Cloud Pub/Sub automatically scales as you need it and provides a foundation for building your own robust, global services.

// Publish "hello world" on topic1.
msgIDs, err := pubsub.Publish(ctx, "topic1", &pubsub.Message{
	Data: []byte("hello world"),
})
if err != nil {
	log.Println(err)
}
// Pull messages via subscription1.
msgs, err := pubsub.Pull(ctx, "subscription1", 1)
if err != nil {
	log.Println(err)
}

Contributing

Contributions are welcome. Please, see the CONTRIBUTING document for details. We're using Gerrit for our code reviews. Please don't open pull requests against this repo, new pull requests will be automatically closed.

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms. See Contributor Code of Conduct for more information.

Documentation

Overview

Package cloud contains Google Cloud Platform APIs related types and common functions.

Index

• func NewContext(projID string, c *http.Client) context.Context
• func WithContext(parent context.Context, projID string, c *http.Client) context.Context
• type ClientOption
  • func WithBaseGRPC(conn *grpc.ClientConn) ClientOption
  • func WithBaseHTTP(client *http.Client) ClientOption
  • func WithEndpoint(url string) ClientOption
  • func WithGRPCConnectionPool(size int) ClientOption
  • func WithGRPCDialOption(o grpc.DialOption) ClientOption
  • func WithScopes(scope ...string) ClientOption
  • func WithTokenSource(s oauth2.TokenSource) ClientOption
  • func WithUserAgent(ua string) ClientOption

Functions

func NewContext

func NewContext(projID string, c *http.Client) context.Context

NewContext returns a new context that uses the provided http.Client. Provided http.Client is responsible to authorize and authenticate the requests made to the Google Cloud APIs. It mutates the client's original Transport to append the cloud package's user-agent to the outgoing requests. You can obtain the project ID from the Google Developers Console, https://console.developers.google.com.

func WithContext

func WithContext(parent context.Context, projID string, c *http.Client) context.Context

WithContext returns a new context in a similar way NewContext does, but initiates the new context with the specified parent.

Types

type ClientOption

type ClientOption interface {
	// Resolve returns the equivalent option from the
	// google.golang.org/api/option package.
	Resolve() option.ClientOption
}

ClientOption is used when construct clients for each cloud service.

func WithBaseGRPC

func WithBaseGRPC(conn *grpc.ClientConn) ClientOption

WithBaseGRPC returns a ClientOption that specifies the gRPC client connection to use as the basis of communications. This option many only be used with services that support gRPC as their communication transport.

func WithBaseHTTP

func WithBaseHTTP(client *http.Client) ClientOption

WithBaseHTTP returns a ClientOption that specifies the HTTP client to use as the basis of communications. This option may only be used with services that support HTTP as their communication transport.

func WithEndpoint

func WithEndpoint(url string) ClientOption

WithEndpoint returns a ClientOption that overrides the default endpoint to be used for a service.

func WithGRPCConnectionPool

func WithGRPCConnectionPool(size int) ClientOption

WithGRPCConnectionPool returns a ClientOption that creates a pool of gRPC connections that requests will be balanced between. This is an EXPERIMENTAL API and may be changed or removed in the future.

func WithGRPCDialOption

func WithGRPCDialOption(o grpc.DialOption) ClientOption

WithGRPCDialOption returns a ClientOption that appends a new grpc.DialOption to an underlying gRPC dial. It does not work with WithBaseGRPC.

func WithScopes

func WithScopes(scope ...string) ClientOption

WithScopes returns a ClientOption that overrides the default OAuth2 scopes to be used for a service.

func WithTokenSource

func WithTokenSource(s oauth2.TokenSource) ClientOption

WithTokenSource returns a ClientOption that specifies an OAuth2 token source to be used as the basis for authentication.

func WithUserAgent

func WithUserAgent(ua string) ClientOption

WithUserAgent returns a ClientOption that sets the User-Agent.