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API Keys

What is this doc?

  1. If there are features which use Google APIs that you need for a custom build, fork, or integration of stock Chromium.
  2. If you are building ChromiumOS yourself, as API access is required for login.
Note: Software distribution with keys acquired for yourself is allowed, but the keys themselves cannot be shared with parties outside the legal entity that accepted the API ToS. Keep in mind that a number of the APIs will have no or very limited quota and not all of the APIs have additional quota available for purchase.
Googlers only:
How-to:
First, acquire API keys. Then, specify the API keys to use either when you build Chromium, or at runtime using environment variables.

Acquiring Keys

  1. Make sure you are a member of chromium-dev@chromium.org (you can just subscribe to chromium-dev and choose not to receive mail). Note: the APIs below are only visible to people subscribed to that group.
  2. Make sure you are logged in with the Google account associated with the email address that you used to subscribe to chromium-dev.
  3. Go to https://cloud.google.com/console
  4. Click on the dropdown next to "Google Cloud Platform" and select Create Project (upper right).
  5. (Optional) You may add other members of your organization or team on the Team tab.
  6. Open the APIs and Services > Library from the hamburger menu, search for all of the following APIs. If you're a member of the chromeos-dev Google group you should see all of them. For each of these APIs click on them when found by the search, and then click on "Enable API" button at the top, read and agree to the Terms of Service that is shown, check the "I have read and agree to <API name> Terms of Service" checkbox and click Accept: (This list might be out of date; try searching for APIs starting with "Chrome" or having "for Chrome" in the name.)
    • Cloud Search API
    • Geolocation API (requires enabling billing but is free to use; you can skip this one, in which case geolocation features of Chrome will not work)
    • Google Drive API (enable this for Files.app on Chrome OS and SyncFileSystem API)
    • Safe Browsing API
    • Time Zone API
    • Optional
      • Admin SDK
      • Cloud Translation API
      • Geocoding API
      • Google Assistant API
      • Google Calendar API
      • Nearby Messages API
    If any of these APIs are not shown, recheck step 1.
  1. Go to the Credentials sub tab under the API & Services section in the hamburger menu.
  2. Click the "Create credentials" button then click on the OAuth client ID item in the drop-down list.
    • Click on the "Configure consent screen" button. Fill in the "Product name" (name it anything you want) and other details if you have available then click on "Save" at the bottom. 
    • Return to the Credentials tab and click the "Add credentials" button again, then select "OAuth 2.0 client ID" from the drop-down list.
    • In the "Application type" section check the "Other" option and give it a name in the "Name" text box, then click "Create"
  3. In the pop-up window that appears you'll see a client ID and a "client secret" string. Copy and paste those in a text file on your dev box then click OK to dismiss it.
    • A new item should now appear in the "OAuth 2.0 client IDs" list. You can click on the name of your client id to retrieve the ID and secret at any time. In the next sections, we will refer to the values of the “Client ID” and “Client secret” fields.
  4. Click the Create credentials button again on the same page.
    • In the pop-over window that shows up click the API key button.
    • A pop-over should show up giving you the API key. Copy and paste it in a text file to save it, although you can access it later as well.
    • Click OK to dismiss this.
You should now have an API key and a OAuth 2.0 client ID in on the Credentials tab. The next sections will refer to the value of the “API key” field too.

Note: that the keys you have now acquired are not for distribution purposes and must not be shared with other users.

Providing Keys at Build Time

If you are building Chromium yourself, you can provide keys as part of your build configuration, that way they are always baked into your binary.
Specify three variables in your args.gn file (which you can edit by running gn args out/your_out_dir_here)
google_api_key = "your_api_key"
google_default_client_id = "your_client_id"
google_default_client_secret = "your_client_secret"

Providing Keys at Runtime

If you prefer, you can build a Chromium binary (or use a pre-built Chromium binary) without API keys baked in, and instead provide them at runtime. To do so, set the environment variables GOOGLE_API_KEY, GOOGLE_DEFAULT_CLIENT_ID and GOOGLE_DEFAULT_CLIENT_SECRET to your "API key", "Client ID" and "Client secret" values respectively.
On Chromium OS to specify the keys as environment variables append them to the end of /etc/chrome_dev.conf:
GOOGLE_API_KEY=your_api_key
GOOGLE_DEFAULT_CLIENT_ID=your_client_id
GOOGLE_DEFAULT_CLIENT_SECRET=your_client_secret

Signing in to Chromium is restricted

Signing in to Chromium requires an OAuth 2.0 token for authentication. As this OAuth 2.0 token gives access to various Google services that handle user data (e.g. Chrome sync), for security and privacy reasons the generation of this OAuth 2.0 token is restricted. This means that signing in to Chromium is restricted (as the OAuth 2.0 token cannot be generated). In order to sign in to Chromium builds, please add your test account to google-browser-signin-testaccounts@chromium.org (accounts in this group are allowed to get access tokens bypassing the restriction above).


Note: Starting with Chromium M69, when the browser is set up with an OAuth 2.0 client ID and client secret, signing in with your Google Account to any Google web property will also attempt to sign you in to Chromium (which will fail as explained above). To avoid such errors, remove your OAuth 2.0 client ID and client secret from your build to stop generating tokens when users sign in to Google web properties (remove google_default_client_id, google_default_client_secret from gn args and GOOGLE_DEFAULT_CLIENT_ID and GOOGLE_DEFAULT_CLIENT_SECRET from your environment settings).

Getting Keys for Your Chromium Derivative

Many of the Google APIs used by Chrome are specific to Google and not intended for use in derived products. In the API Console (http://developers.google.com/console) you may be able to purchase additional quota for some of the APIs listed above.  For APIs that do not have a "Pricing" link, additional quota is not available for purchase.

Polyfilling chrome.identity API in Your Chromium Derivative
The default Chromium chrome.identity.getAuthToken API that extensions may call to obtain auth tokens will fail outside of Google Chrome as the implementation uses restricted APIs. 

A prototype CL for Chromium embedders might use to replace the implementation with one not dependent upon private APIs can be found attached to this post. 




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