As we know, the development process happens in two phases: the design phase and the development phase. In the design phase, we design the API with API Designer and give it to the user for testing, and let the actual code get ready later to meet the spec. Let's get started.
1. Sign up for the Anypoint Platform.
2. Find the API Manager link.
3. The below page will appear. Click on the link that I've highlighted.
4. Click on Add New API to get started.
5. Provide the API name and the Version name.
6. The page will show Project explorer, Editor, Shelf, and the API Console.
7. Rename the existing RAML file based on your requirements.
8. The RAML code for the Customer API is the resource customer, which has methods like Get Customer and Get Customer by ID.
9. Activate the mocking service.
10. To run the RAML API definition, click on GET on the API Console. The following response will be shown.
And that's it!