Advanced Feature API:

Google Apps and its APIs open up a wide variety of new opportunities to integrate and extend Google's communication and collaboration services. Domain adminstrators can use the APIs to migrate from and integrate with existing IT infrastructure. Application developers and systems integrators can use the APIs to extend, customize, and integrate Google's growing offering of services.

Domain Administrator:

During adoption of Google Apps, the following APIs can be leveraged to migrate data from systems currently in use and to maintain stability in business processes through deep system integration.

Provisioning API

The Provisioning API provides a mechanism to programmatically create and manage Google Apps user accounts, nicknames, and groups. Using this API you can minimize disruption to your organization's current processes by synchronizing user data between Google Apps and your existing user management system. This API is only available in Google Apps Premier, Education and Partner Editions.

Reporting API

The Reporting API allows you to monitor the overall usage and utilization of Google Apps within your domain. Using this API, you can download a variety of CSV formatted reports about activity, storage, status, and more. This API is only available in Google Apps Premier, Education and Partner Editions.

Email Migration API

The Email Migration API enables you to migrate email from any data source into Google Apps. You can write extraction code which operates against an email server data store, interface protocol, or email client data store, then, using this API, upload the email messages to a target mailbox, specifying the correct labels, date, and status. The Email Migration API supports both end user tools and administrative tools. This API is only available in Google Apps Premier, Education and Partner Editions.

Email Settings API

The Email Settings API enables you to modify user-level Google Mail settings for any of the users at your domain. Using this API, you can change a user's forwarding, POP, or IMAP settings, set up an alias for them to send e-mail as, and more. This API is only available in Google Apps Premier, Education and Partner Editions.

Single Sign-On Service

This service interface allows you to plug in your own identity provider to authenticate users who are trying to access Google Apps services. By implementing the interface you retain ownership and management of user credentials and avoid requiring users to remember yet another password. It's based on the SAML v2.0 Standard XML-based framework for communicating user authentication information between business entities. The single sign-on service is only available in Google Apps Premier, Education and Partner Editions.

Email Gateway Interface

Incoming and outgoing email can be routed through a mail gateway, giving you a tremendous amount of control and flexibility. Smooth out the adoption process by simultaneously delivering email to both Google Apps and your existing system. Adhere to message content policies like filtering out sensitive content or adding a footer to all messages. Meet auditing requirements for regulatory compliance and data retention obligations for disaster recovery. This interface is only available in Google Apps Premier, Education and Partner Editions.

Calendar Data API

The Google Calendar data API provides a mechanism to programmatically create and manage Google Calendar event data. You can use it to seamlessly replace your current calendar system by migrating scheduled events to Google Apps. You can also publish data from other event-based applications through the Google Calendar user interface or embed Google Calendar event information in a custom front end application.

2-legged OAuth Google Data access

While OAuth authentication is available to all developers wishing to access the Google Data APIs, Premier and Education Edition administrators can enable a special kind of OAuth, called 2-legged OAuth. 2-legged OAuth allows administrators to act on behalf of end-users without their involvement and without requiring an access token as per the normal authorization flow(3-legged OAuth). As an example, administrators can use this feature to upload new documents to a user's account, add events to their Google Calendar, or create a new contact in their address book, all without the end-user's involvement.

Application Developers

The following APIs provide the flexibility for application developers, systems integrators, independent software vendors, and users to extend, customize, publish into, and integrate with the services offered through Google Apps.

Google Data APIs

The Google data APIs provide a simple standard protocol for reading and writing data on the web. An increasing number of Google services provide data APIs, so application developers should become familiar with the protocol. The data APIs are based on the Atom and RSS syndication formats and the Atom publishing protocol, and also includes support forauthentication, querying, and version conflict detection. Client applications can use any programming language that can issue HTTP requests and parse XML-based responses. Client libraries are avaialable in a variety of popular languages.

Calendar Data API

The Google Calendar data API allows client applications to create new events, edit or delete existing events, and query for events that match particular criteria. This is the same API that is available to all Google Calendar developers so Google Apps developers can leverage and participate in that growing community. However with Google Apps a whole new set of calendar-based business applications become possible. Google Calendar's calendar sharing feature is that much more important in growing organizations with lots of group interactions and overlapping schedules. A client application has access to its user's private and accessible shared and group calendars. Application developers can interact with these calendars by creating front end applications powered by their event information or by creating applications that publish event information to them.

Contacts Data API

With the Google Contacts Data API, developers can create client applications to manage a user's Gmail contacts. Developers can use the API to synchronize a user's Google contacts with contacts on a mobile device, maintain relationships between people in social applications, and give users the ability to communicate directly with their friends from external applications using phone, email, and IM.

Documents List Data API

The Google Documents List Data API allows client applications to manage a user's Google Documents (spreadsheets, word processor, presentations) using the Google Data protocol. Your client application can query a user's list of documents, manage folders, request or update the contents of a document, and upload, edit, or delete specific documents.

Spreadsheets Data API

The Google Spreadsheets data API allows client applications to view and update spreadsheets content. This is the same API that is available to all Google Spreadsheets developers so Google Apps developers can leverage and participate in that growing community. Spreadsheets are at the heart of an increasing number of critical business applications ranging from modeling and analysis to communication and plannng. A client application can use this API to implement spreadsheet functionality or to extend the functionality provided by Google Spreadsheets. It can also simply use a spreadsheet as a database back end or it can publish data to a spreadsheet to provide users a more expressive view.

Google Gadgets API

Google Apps services are all unified by the Start Page which can include little web applications created using the Google Gadgets API. They can then be added directly to a Google Apps Start Page by a user that has the gadget's URL. Alternatively they can be added to the organization's content directory by an administrator.

Google Talk open protocols

The Google Talk instant messaging service uses the XMPP open protocol allowing client applications to hook into the service to provide peer-to-peer messaging, presence information, voice, and file transfer. This also allows other services implementing the XMPP standard to be federated with the Google Talk service so all of an organization's users can communicate in real time.

Gmail Inbox feed

Apps developers can utilize Gmail's Atom feed to request read-only access to a user's unread messages. To obtain access, you can use AuthSub or OAuth by requesting a token with scope=https://mail.google.com/mail/feed/atom/.