This video explains how to get the list of mapping task using REST API.
References
For more information, refer the following documents:
Login V2 call: https://docs.informatica.com/cloud-common-services/administrator/current-version/rest-api-reference/platform-rest-api-version-2-resources/login.html
Login V3 call: https://docs.informatica.com/cloud-common-services/administrator/current-version/rest-api-reference/platform-rest-api-version-3-resources/login.html
Mapping task: https://docs.informatica.com/cloud-common-services/administrator/current-version/rest-api-reference/data-integration-rest-api/mapping-tasks.html