This course will dive deeper into how to implement Frends API endpoints. Here you will learn how to build Linked Processes, how to handle headers as well as query and path parameters in you endpoints. We will introduce Intermediate Return Element and go through some use cases for it. We will see how to test the Linked Processes using Manual Trigger and go through most common API errors messages and how to debug them in Frends.
Getting started
The Frends API endpoints are implemented following the API specification which is written either in YAML or JSON and based on OpenAPI specification. You will also need to have the designs for the operations and a decision made of how to handle authentication with each specific endpoint. Information on which Agent Group the APIs will be deployed is highly important.
The actual endpoints are build as regular Processes. You have two choices which you can follow to get you started with creating Linked Process. First option is to create the Process from the API view by pressing the Create new Process from a new API endpoint specification. This will open up the Process Editor with ready made API Trigger, HTTP Response Return Element and a HTTP Response Throw Element in it which are configured as is in the API specification.
The other option is to create a new Process with traditional way and manually adding the Trigger, Return and Throw Elements. When doing it this way, the Process Editor will suggest you what API endpoints are available to implement. Note that you first need to create the endpoint in the API specification before you can start to implement it in the Process Editor. This method allows you to change already made Processes into API Linked Processes. You can have only one Linked Process to a specific API endpoint and the Process Editor will throw an exception if the endpoint has already been made. Also a Process can have just one API Trigger attached to it. This disables you to build Processes which are listening different endpoints in the API.
The next article is Example on Building a Linked Process.