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Expose REST APIs

OutSystems allows you to expose methods using a REST API. Those methods can be organized under multiple 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.

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