Expose REST APIs

REST API Method Flow

When a request to your REST API Method is received, OutSystems executes the following flow:

1. Security Validations: After receiving the REST API Method request, OutSystems executes the security validations according to the settings in REST API properties HTTP Security and Internal Access Only.
2. OnRequest(): OnRequest callback allows you to run logic over the requests after receiving them.
3. OnAuthentication(): OnAuthentication callback allows you to add basic authentication or custom authentication to requests.
4. Parameters Deserialization and Validation: Deserialization of the input parameters and validation of the data types, mandatory values, etc.
5. Execute Method: Executes the action that implements the REST API Method.
6. Parameters Serialization: Serialization of the output parameters to return in the response.
7. OnResponse(): OnResponse callback allows you to run logic over the responses before sending them. It is always executed, even in an error situation.

Articles in this Section

• Expose a REST API

  Expose a REST API to allow other systems to retrieve or manipulate information.

• Add Basic Authentication to an Exposed REST API

  Add basic authentication to the requests made to the REST APIs you are exposing.

• Add Custom Authentication to an Exposed REST API

  Improve the security of exposed REST APIs by adding custom authentication logic.

• Customize REST URLs

  Customize the URL of your exposed REST API methods according to your needs.

• Customize REST API Responses

  Customize the information sent in responses when exposing a REST API.

• Preprocess REST API Requests

  How to run logic before executing each request of an exposed REST API.

• Change the HTTP Status Code of a REST API

  How to send a specific HTTP Status Code in the response of an exposed REST API method.

• Throw a Custom Error in an Exposed REST API

  Check how you can send meaningful errors when a REST API method runs into an error.

• Document an Exposed REST API

  Add documentation to your REST API to help developers to integrate their applications with your system.