Creating a service
==================

Now that we have our :doc:`./creating`,
we can create a new API endpoint to store messages.

Generating a service
--------------------

In Feathers any API endpoint is represented as a
:doc:`../../api/services`, which we already learned about in
the :doc:`../basics/services`. To generate a new service,
we can run:

.. code-block:: sh

   feathers generate service

First we have to choose what kind of service we’d like to create. You
can choose amongst many databases and ORMs but for this guide we will go
with the default `NeDB <https://github.com/louischatriot/nedb>`_. NeDB
is a database that stores its data locally in a file and requires no
additional configuration or database server.

Next, when asked for the name of the service, enter ``messages``. Then
keep the default path (``/messages``) by pressing enter.

The *database connection string* can also be answered with the default.
(In this case of NeDB, this is the path where it should store its
database files.)

Confirming the last prompt will generate some files and wire our service
up:

.. figure:: ./assets/service.png
   :alt: Final Configuration

   Final Configuration

Et voilà! We have a fully functional REST and real-time API for our
messages.

The generated files
-------------------

As we can see, several files were created:

-  ``src/services/messages/messages.service.js`` - The service setup
   file which registers the service in a :doc:`../basics/generator`
-  ``src/services/messages/messages.hooks.js`` - A file that returns an
   :doc:`../basics/hooks` that should be
   registered on the service.
-  ``src/models/messages.model.js`` - The model for our messages. Since
   we are using NeDB, this will simply instantiate the filesystem
   database.
-  ``test/services/messages.test.js`` - A Mocha test for the service.
   Initially, it only tests that the service exists.

Testing the API
---------------

If we now start our API with

.. code-block:: sh

   npm start

We can go to
`localhost:3030/messages <http://localhost:3030/messages>`_ and will
see an (empty) response from our new messages service.

We can also ``POST`` new messages and ``PUT``, ``PATCH`` and ``DELETE``
existing messages (via ``/messages/<_id>``), for example from the
command line using `CURL <https://curl.haxx.se/>`_:

.. code-block:: sh

   curl 'http://localhost:3030/messages/' -H 'Content-Type: application/json' --data-binary '{ "text": "Hello from the command line!" }'

Or with a REST client,
e.g. \ `Postman <https://chrome.google.com/webstore/detail/postman/fhbjgbiflinjbdggehcddcbncdddomop?hl=en>`_,
using this button:

|Run in Postman|

If we now go to
`localhost:3030/messages <http://localhost:3030/messages>`_ again we
will see the newly created message(s).

What’s next?
------------

With just one command, we created a fully functional REST and real-time
API endpoint. Next, let’s :doc:`./authentication`
and make sure messages only go to users that are allowed to see them.

.. |Run in Postman| image:: https://run.pstmn.io/button.svg
   :target: https://app.getpostman.com/run-collection/9668636a9596d1e4a496