Implementing OAuth 2.0 Authorization

The YouTube Data API supports the OAuth 2.0 protocol for authorizing access to private user data. The list below explains some core OAuth 2.0 concepts:

• When a user first attempts to use functionality in your application that requires the user to be logged in to a Google Account or YouTube account, your application initiates the OAuth 2.0 authorization process.

• Your application directs the user to Google's authorization server. The link to that page specifies the scope of access that your application is requesting for the user's account. The scope specifies the resources that your application can retrieve, insert, update, or delete when acting as the authenticated user.

• If the user consents to authorize your application to access those resources, Google returns a token to your application. Depending on your application's type, it either validates the token or exchanges it for a different type of token.

  For example, a server-side web application exchanges the returned token for an access token and a refresh token. The access token lets the application authorize requests on the user's behalf, and the refresh token lets the application retrieve a new access token when the original access token expires.

Important: You need to obtain authorization credentials in the Google Developers Console to be able to use OAuth 2.0 authorization.

OAuth 2.0 flows

Google APIs support several OAuth 2.0 use cases:

• The server-side flow supports web applications that can securely store persistent information.
• The client-side flow supports JavaScript applications running in a browser.
• The installed application flow supports applications installed on a device, such as a phone or computer.
• The device flow supports devices with limited input capabilities, such as game consoles and video cameras.
• The service account flow supports server-to-server interactions that do not access user information. However, the YouTube Data API does not support this flow. Since there is no way to link a Service Account to a YouTube account, attempts to authorize requests with this flow will generate a NoLinkedYouTubeAccount error.