# Google API Client
Homepage
http://www.github.com/google/google-api-ruby-client
Authors
Bob Aman, Steven Bazyl
Copyright
Copyright © 2011 Google, Inc.
License
Apache 2.0
[![Build Status](https://secure.travis-ci.org/google/google-api-ruby-client.png)](http://travis-ci.org/google/google-api-ruby-client) [![Dependency Status](https://gemnasium.com/google/google-api-ruby-client.png)](https://gemnasium.com/google/google-api-ruby-client) ## Description The Google API Ruby Client makes it trivial to discover and access supported APIs. ## Alpha This library is in Alpha. We will make an effort to support the library, but we reserve the right to make incompatible changes when necessary. ## Install Be sure `https://rubygems.org/` is in your gem sources. For normal client usage, this is sufficient: ```bash $ gem install google-api-client ``` ## Example Usage ```ruby require 'google/api_client' require 'google/api_client/client_secrets' require 'google/api_client/auth/installed_app' # Initialize the client. client = Google::APIClient.new( :application_name => 'Example Ruby application', :application_version => '1.0.0' ) # Initialize Google+ API. Note this will make a request to the # discovery service every time, so be sure to use serialization # in your production code. Check the samples for more details. plus = client.discovered_api('plus') # Load client secrets from your client_secrets.json. client_secrets = Google::APIClient::ClientSecrets.load # Run installed application flow. Check the samples for a more # complete example that saves the credentials between runs. flow = Google::APIClient::InstalledAppFlow.new( :client_id => client_secrets.client_id, :client_secret => client_secrets.client_secret, :scope => ['https://www.googleapis.com/auth/plus.me'] ) client.authorization = flow.authorize # Make an API call. result = client.execute( :api_method => plus.activities.list, :parameters => {'collection' => 'public', 'userId' => 'me'} ) puts result.data ``` ## API Features ### API Discovery To take full advantage of the client, load API definitions prior to use. To load an API: ```ruby urlshortener = client.discovered_api('urlshortener') ``` Specific versions of the API can be loaded as well: ```ruby drive = client.discovered_api('drive', 'v2') ``` Locally cached discovery documents may be used as well. To load an API from a local file: ```ruby # Output discovery document to JSON File.open('my-api.json', 'w') do |f| f.puts MultiJson.dump(client.discovery_document('myapi', 'v1')) end # Read discovery document and load API doc = File.read('my-api.json') client.register_discovery_document('myapi', 'v1', doc) my_api = client.discovered_api('myapi', 'v1') ``` ### Authorization Most interactions with Google APIs require users to authorize applications via OAuth 2.0. The client library uses [Signet](https://github.com/google/signet) to handle most aspects of authorization. For additional details about Google's OAuth support, see [Google Developers](https://developers.google.com/accounts/docs/OAuth2). Credentials can be managed at the connection level, as shown, or supplied on a per-request basis when calling `execute`. For server-to-server interactions, like those between a web application and Google Cloud Storage, Prediction, or BigQuery APIs, use service accounts. As of version 0.8.3, service accounts can be configured using [Application Default Credentials][1], which rely on the credentials being available in a well-known location. If the credentials are not present and it's being used on a Compute Engine VM, it will use the VM's default credentials. ```ruby client.authorization = :google_app_default # in a later version, this will become the default client.authorization.fetch_access_token! client.execute(...) ``` This is simpler API to use than in previous versions, although that is still available: ```ruby key = Google::APIClient::KeyUtils.load_from_pkcs12('client.p12', 'notasecret') client.authorization = Signet::OAuth2::Client.new( :token_credential_uri => 'https://accounts.google.com/o/oauth2/token', :audience => 'https://accounts.google.com/o/oauth2/token', :scope => 'https://www.googleapis.com/auth/prediction', :issuer => '123456-abcdef@developer.gserviceaccount.com', :signing_key => key) client.authorization.fetch_access_token! client.execute(...) ``` Service accounts are also used for delegation in Google Apps domains. The target user for impersonation is specified by setting the `:person` parameter to the user's email address in the credentials. Detailed instructions on how to enable delegation for your domain can be found at [developers.google.com](https://developers.google.com/drive/delegation). ### Automatic Retries & Backoff The API client can automatically retry requests for recoverable errors. To enable retries, set the `client.retries` property to the number of additional attempts. To avoid flooding servers, retries invovle a 1 second delay that increases on each subsequent retry. In the case of authentication token expiry, the API client will attempt to refresh the token and retry the failed operation - this is a specific exception to the retry rules. The default value for retries is 0, but will be enabled by default in future releases. ### Batching Requests Some Google APIs support batching requests into a single HTTP request. Use `Google::APIClient::BatchRequest` to bundle multiple requests together. Example: ```ruby client = Google::APIClient.new urlshortener = client.discovered_api('urlshortener') batch = Google::APIClient::BatchRequest.new do |result| puts result.data end batch.add(:api_method => urlshortener.url.insert, :body_object => { 'longUrl' => 'http://example.com/foo' }) batch.add(:api_method => urlshortener.url.insert, :body_object => { 'longUrl' => 'http://example.com/bar' }) client.execute(batch) ``` Blocks for handling responses can be specified either at the batch level or when adding an individual API call. For example: ```ruby batch.add(:api_method=>urlshortener.url.insert, :body_object => { 'longUrl' => 'http://example.com/bar' }) do |result| puts result.data end ``` ### Media Upload For APIs that support file uploads, use `Google::APIClient::UploadIO` to load the stream. Both multipart and resumable uploads can be used. For example, to upload a file to Google Drive using multipart ```ruby drive = client.discovered_api('drive', 'v2') media = Google::APIClient::UploadIO.new('mymovie.m4v', 'video/mp4') metadata = { 'title' => 'My movie', 'description' => 'The best home movie ever made' } client.execute(:api_method => drive.files.insert, :parameters => { 'uploadType' => 'multipart' }, :body_object => metadata, :media => media ) ``` To use resumable uploads, change the `uploadType` parameter to `resumable`. To check the status of the upload and continue if necessary, check `result.resumable_upload`. ```ruby client.execute(:api_method => drive.files.insert, :parameters => { 'uploadType' => 'resumable' }, :body_object => metadata, :media => media ) upload = result.resumable_upload # Resume if needed if upload.resumable? client.execute(upload) end ``` ## Samples See the full list of [samples on Github](https://github.com/google/google-api-ruby-client-samples). ## Support Please [report bugs at the project on Github](https://github.com/google/google-api-ruby-client/issues). Don't hesitate to [ask questions](http://stackoverflow.com/questions/tagged/google-api-ruby-client) about the client or APIs on [StackOverflow](http://stackoverflow.com). [1]: https://developers.google.com/accounts/docs/application-default-credentials