Authenticate to Common Data Service with the Web API

You must use OAuth as described in Use OAuth with Common Data Service.

The code you write to manage authentication when using the Web API depends on the type of deployment and where your code is.

Authenticate with JavaScript in web resources

When you use the Web API with JavaScript within HTML web resources, form scripts, or ribbon commands you don’t need to include any code for authentication. In each of these cases the user is already authenticated by the application and authentication is managed by the application.

If you’re creating a single page application (SPA) using JavaScript you can use the adal.js library as described in Use OAuth with Cross-Origin Resource Sharing to connect a Single Page Application.

See also

Use the Common Data Service Web API
Web API types and operations
Perform operations using the Web API
Use OAuth with Common Data Service
Use OAuth with Cross-Origin Resource Sharing to connect a Single Page Application