OAuth 2.0 is the current standard for managing user access to websites or application resources and provides client credential flow for modern APIs. It allows resource owners to grant access to protected resources by issuing clients access tokens, which improves on previous OAuth standards. The protocol offers a robust means of authorizing third-party applications per the consent of resource-owning users. OAuth 2.0 is not limited to REST APIs and can be layered on top of GraphQL using the client credential flow to provide scoped, protected access to GraphQL clients for user resources. Integrating OAuth 2.0 into a GraphQL application involves managing client ID, client secret, and access token artifacts. A client ID uniquely identifies third-party applications, while the client secret is a credential known only to the authorization server and a third-party application. The access token authorizes a third-party application and must be kept confidential at all times. To implement OAuth 2.0 in GraphQL using Node.js, developers can create an Application with Propel Data, register it, and then bootstrap the Application by creating a structure for the propel-oauth2 project. This involves installing cross-fetch and dotenv libraries, placing client ID and secret in the .env file, and fetching the OAuth 2.0 access token from Propel's API. The access token can be used to make requests to Propel's GraphQL API, which includes the access token inside the Authorization header. Finally, developers put each artifact together into a single entry script named index.mjs, calling the fetchPropelAccessToken and fetchPropelMetrics functions to retrieve an access token and metrics for their Propel account.