Google APIs

This repository contains the original interface definitions for a small (but growing) set of Google APIs built on a next-generation API serving stack. Reading the original interface definitions can provide a better understanding of these APIs and help you to utilize them more efficiently. You can also use these interface definitions with open source tools to generate client libraries or other artifacts such as documentation.

For more details on all Google APIs and developer tools, see the Google Developers site.

Overview

Google APIs are typically deployed as API services that are hosted under different DNS names. One API service may implement multiple APIs and multiple versions of the same API, and each API contains a collection of API methods.

By default, Google APIs use Protocol Buffers language version 3 - aka proto3 - as their Interface Definition Language (IDL) to define the API interface and the structure of the payload messages. The same interface definition is used for both REST and RPC versions of the API, which can be accessed over different wire protocols.

There are two ways of accessing Google APIs:

1. JSON over HTTP/1.1: You can access Google APIs directly using JSON over HTTP/1.1, using Google-provided API or third-party API client libraries.

2. Protocol Buffers over gRPC: You can access Google APIs published in this repository through GRPC, which is a high-performance binary RPC protocol over HTTP/2. It offers many useful features, including request/response multiplex and full-duplex streaming.

Discussions

You may use the Google APIs mailing list for general discussions about this repository.

Repository Structure

This repository uses a directory hierarchy that reflects the Google API product structure. In general, every API has its own root directory, and each major version of the API has its own subdirectory. The proto package names exactly match the directory: this makes it easy to locate the proto definitions and ensures that the generated client libraries have idiomatic namespaces in most programming languages. Alongside the API directories live the configuration files for the GAPIC toolkit.

NOTE: the major version of an API is used to indicate breaking change to the API.

Generate gRPC Source Code

To generate gRPC source code for Google APIs in this repository, you first need to install both Protocol Buffers and gRPC on your local machine. Then you can run make all in this directory to generate the code.

NOTE: The Makefile needs more improvements.