Running the local development web server

With the local SQLite database now in place, you can run your application by executing the python3 manage.py runserver command, which starts a local development web server on port 8000:

src> python3 manage.py runserver
Performing system checks...

System check identified no issues (0 silenced).
July 02, 2018 - 07:23:49
Django version 2.0, using settings 'todobackend.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.

If you open a browser to http://localhost:8000/, you should see a web page titled Django REST framework:

This page is the root of the application, and you can see that the Django REST framework provides a graphical interface for navigating the API when you use a browser.  If you use the curl command instead of a browser, notice that Django detects a simple HTTP client and just returns a JSON response:

src> curl localhost:8000
{"todos":"http://localhost:8000/todos"}

If you click on the hypermedia link for the todos item (http://localhost:8000/todos), you will be presented with a list of Todo items, which is currently empty:

Notice that you can create a new Todo item with a title and order using the web interface, which will populate the list of Todo items once you click on the POST button:

Of course, you also can use the command line and the curl command to create new Todo items, list all Todo items, and update Todo items:

> curl -X POST -H "Content-Type: application/json" localhost:8000/todos \
       -d '{"title": "Wash the car", "order": 2}'
{"url":"http://localhost:8000/todos/2","title":"Wash the car","completed":false,"order":2}

> curl -s localhost:8000/todos | jq
[
 {
 "url": "http://localhost:8000/todos/1",
 "title": "Walk the dog",
 "completed": false,
 "order": 1
 },
 {
 "url": "http://localhost:8000/todos/2",
 "title": "Wash the car",
 "completed": false,
 "order": 2
 }
]

> curl -X PATCH -H "Content-Type: application/json" localhost:8000/todos/2 \
       -d '{"completed": true}' 
{"url":"http://localhost:8000/todos/2","title":"Wash the car","completed":true,"order":1}

In the preceding example, you first create a new Todo item using the HTTP POST method, and then verify that the Todos list now contains two Todo items, piping the output of the curl command to the jq utility you installed previously to format the returned items.  Finally, you use the HTTP PATCH method to make a partial update to the Todo item, marking the item as completed.

All of the Todo items you created and modified will be persisted in the application database, which in this case is a SQLite database running on your development machine.