Documentation Learn more about the built-in REST API for Yello CRM


This demo requires Database configured. Please head over to the database installation page to play around with it.


Representational State Transfer (REST) is a software architectural style that defines a set of constraints to be used for creating Web services. Web services that conform to the REST architectural style, called RESTful Web services (RWS), provide interoperability between computer systems on the Internet.

from wikipedia

Yello CRM has built-in REST API server that you can already use out of the box. Provided that you enabled mod_rewrite in the installation, you can configure your REST API server in minutes!

To play around with this feature, head over to the API Tester page.


The API routes are basically the endpoints of your API. These routes are configured/defined under public/api folder. To learn more on how to design your API better, follow this tutorial about REST apis.

Example route request:



HTTP/1.1 200 OK
    "id": 1,
    "username": "lodev09",
    "name": "Jovanni",
    "email": "",
    "created_at": "2019-07-02T19:34:22Z"


Yello CRM includes various middlewares to handle each request. For example, the \API\AuthMiddleware where it validates the user credentials passed through the Authentication header -- basically checking if the request is authenticated or not.

Here are the included middlewares:

Class Description
\API\AuthMiddleware Authenticates requests
\API\LoggerMiddleware Logs requests
\API\RateLimitMiddleware Calculates rate limits
\API\RequestMiddleware Converts all requests to JSON


The built-in REST API server comes with the Authentication routine which is handled by the \API\AuthMiddleware middleware. Check out the Authentication documentation to learn more.


Yello CRM uses slimphp/Slim package to host the API server. Refer to their documentation on how to create your own routes and customize your REST API server.