README

Google APIs Client Library for Go

Getting Started

$ go get google.golang.org/api/tasks/v1
$ go get google.golang.org/api/moderator/v1
$ go get google.golang.org/api/urlshortener/v1
... etc ...

and using:

package main

import (
	"net/http"

	"google.golang.org/api/urlshortener/v1"
)

func main() {
	svc, err := urlshortener.New(http.DefaultClient)
	// ...
}

• For a longer tutorial, see the Getting Started guide.
• For examples, see the examples directory.
• For support, use the golang-nuts mailing list.
• The code review instance may be found here.

Status

These are auto-generated Go libraries from the Google Discovery Service's JSON description files of the available "new style" Google APIs.

Due to the auto-generated nature of this collection of libraries, complete APIs or specific versions can appear or go away without notice. As a result, you should always locally vendor any API(s) that your code relies upon.

These client libraries are officially supported by Google. However, the libraries are considered complete and are in maintenance mode. This means that we will address critical bugs and security issues but will not add any new features.

If you're working with Google Cloud Platform APIs such as Datastore or Pub/Sub, consider using the Cloud Client Libraries for Go instead. These are the new and idiomatic Go libraries targeted specifically at Google Cloud Platform Services.

The generator itself and the code it produces are beta. Some APIs are alpha/beta, and indicated as such in the import path (e.g., "google.golang.org/api/someapi/v1alpha").

Application Default Credentials Example

Application Default Credentials provide a simplified way to obtain credentials for authenticating with Google APIs.

The Application Default Credentials authenticate as the application itself, which make them great for working with Google Cloud APIs like Storage or Datastore. They are the recommended form of authentication when building applications that run on Google Compute Engine or Google App Engine.

Default credentials are provided by the golang.org/x/oauth2/google package. To use them, add the following import:

import "golang.org/x/oauth2/google"

Some credentials types require you to specify scopes, and service entry points may not inject them. If you encounter this situation you may need to specify scopes as follows:

import (
        "context"
        "golang.org/x/oauth2/google"
        "google.golang.org/api/compute/v1"
)

func main() {
        // Use oauth2.NoContext if there isn't a good context to pass in.
        ctx := context.Background()

        client, err := google.DefaultClient(ctx, compute.ComputeScope)
        if err != nil {
                //...
        }
        computeService, err := compute.New(client)
        if err != nil {
                //...
        }
}

If you need a oauth2.TokenSource, use the DefaultTokenSource function:

ts, err := google.DefaultTokenSource(ctx, scope1, scope2, ...)
if err != nil {
        //...
}
client := oauth2.NewClient(ctx, ts)

See also: golang.org/x/oauth2/google package documentation.

Documentation

Overview

Package api is the root of the packages used to access Google Cloud Services. See https://godoc.org/google.golang.org/api for a full list of sub-packages.

Within api there exist numerous clients which connect to Google APIs, and various utility packages.

Client Options

All clients in sub-packages are configurable via client options. These options are described here: https://godoc.org/google.golang.org/api/option.

Authentication and Authorization

All the clients in sub-packages support authentication via Google Application Default Credentials (see https://cloud.google.com/docs/authentication/production), or by providing a JSON key file for a Service Account. See the authentication examples in https://godoc.org/google.golang.org/api/transport for more details.

Versioning and Stability

Due to the auto-generated nature of this collection of libraries, complete APIs or specific versions can appear or go away without notice. As a result, you should always locally vendor any API(s) that your code relies upon.

Google APIs follow semver as specified by https://cloud.google.com/apis/design/versioning. The code generator and the code it produces - the libraries in the google.golang.org/api/... subpackages - are beta.

Note that versioning and stability is strictly not communicated through Go modules. Go modules are used only for dependency management.

Integers

Many parameters are specified using ints. However, underlying APIs might operate on a finer granularity, expecting int64, int32, uint64, or uint32, all of whom have different maximum values. Subsequently, specifying an int parameter in one of these clients may result in an error from the API because the value is too large.

To see the exact type of int that the API expects, you can inspect the API's discovery doc. A global catalogue pointing to the discovery doc of APIs can be found at https://www.googleapis.com/discovery/v1/apis.