Step 3 - Create an API Gateway
##############################

The instance is linked with NGINX Controller, but it needs to be configured as a ``Gateway`` to be used by NGINX Controller. A ``Gateway`` is an NGINX Controller object "grouping" instances (not to be confused with an API Gateway).

.. note:: In this lab, we have only one instance per ``Gateway``, but we could have several instances per ``Gateway``. For instance, I could have 3 NGINX Plus instances in front of my API Sentence app. All of these instances would have the same API Definition config.

Steps:

#. In NGINX Controller -> Select ``Home`` (the NGINX logo on the top left corner) -> ``Services`` -> ``Gateways`` -> ``Create Gateway``. Use the following values:
  
  * Name: ``apigw``
  * Environment: ``env_prod``
  * Placement: ``<your nginx1 instance>``
  * Hostname: http://api.name-generator.com
  * Methods: ``POST``, ``GET``, ``PUT``, ``DELETE``, ``PATCH``

#. Click ``Submit``

    .. note:: The hostname value is the listener. This ``Gateway`` will be dedicated to the API FQDN, so we set this FQDN at the ``Gateway`` level.

#. You might notice before submitting that NGINX Controller also gives you the ``API Spec`` call to create this gateway (via Postman for example):

.. code-block:: JSON
   :caption: PUT /api/v1/services/environments/env_prod/gateways/apigw

    {
      "metadata": {
        "name": "apigw",
        "tags": []
      },
      "desiredState": {
        "ingress": {
          "uris": {
            "http://api.name-generator.com": {}
          },
          "methods": [
            "POST",
            "GET",
            "PUT",
            "DELETE",
            "PATCH"
          ],
          "placement": {
            "instanceRefs": [
              {
                "ref": "/infrastructure/locations/unspecified/instances/nginx1"
              }
            ]
          }
        }
      }
    }

|

#. Congrats! You have configured your NGINX Plus instance as a ``Gateway``, and we can now use it for ADC or API management (as an API Gateway) use cases.

.. image:: ../pictures/lab2/apigw.png
   :align: center