The code from my article on building RESTful web services with Python and the Flask microframework. See the article here: http://blog.miguelgrinberg.com/post/designing-a-restful-api-with-python-and-flask

rest-server.py

#!flask/bin/python
from flask import Flask, jsonify, abort, request, make_response, url_for
from flask_httpauth import HTTPBasicAuth

app = Flask(__name__, static_url_path = "")
auth = HTTPBasicAuth()

@auth.get_password
def get_password(username):
    if username == 'miguel':
        return 'python'
    return None

@auth.error_handler
def unauthorized():
    return make_response(jsonify( { 'error': 'Unauthorized access' } ), 403)
    # return 403 instead of 401 to prevent browsers from displaying the default auth dialog
    
@app.errorhandler(400)
def bad_request(error):
    return make_response(jsonify( { 'error': 'Bad request' } ), 400)

@app.errorhandler(404)
def not_found(error):
    return make_response(jsonify( { 'error': 'Not found' } ), 404)

tasks = [
    {
        'id': 1,
        'title': u'Buy groceries',
        'description': u'Milk, Cheese, Pizza, Fruit, Tylenol', 
        'done': False
    },
    {
        'id': 2,
        'title': u'Learn Python',
        'description': u'Need to find a good Python tutorial on the web', 
        'done': False
    }
]

def make_public_task(task):
    new_task = {}
    for field in task:
        if field == 'id':
            new_task['uri'] = url_for('get_task', task_id = task['id'], _external = True)
        else:
            new_task[field] = task[field]
    return new_task
    
@app.route('/todo/api/v1.0/tasks', methods = ['GET'])
@auth.login_required
def get_tasks():
    return jsonify( { 'tasks': map(make_public_task, tasks) } )

@app.route('/todo/api/v1.0/tasks/<int:task_id>', methods = ['GET'])
@auth.login_required
def get_task(task_id):
    task = filter(lambda t: t['id'] == task_id, tasks)
    if len(task) == 0:
        abort(404)
    return jsonify( { 'task': make_public_task(task[0]) } )

@app.route('/todo/api/v1.0/tasks', methods = ['POST'])
@auth.login_required
def create_task():
    if not request.json or not 'title' in request.json:
        abort(400)
    task = {
        'id': tasks[-1]['id'] + 1,
        'title': request.json['title'],
        'description': request.json.get('description', ""),
        'done': False
    }
    tasks.append(task)
    return jsonify( { 'task': make_public_task(task) } ), 201

@app.route('/todo/api/v1.0/tasks/<int:task_id>', methods = ['PUT'])
@auth.login_required
def update_task(task_id):
    task = filter(lambda t: t['id'] == task_id, tasks)
    if len(task) == 0:
        abort(404)
    if not request.json:
        abort(400)
    if 'title' in request.json and type(request.json['title']) != unicode:
        abort(400)
    if 'description' in request.json and type(request.json['description']) is not unicode:
        abort(400)
    if 'done' in request.json and type(request.json['done']) is not bool:
        abort(400)
    task[0]['title'] = request.json.get('title', task[0]['title'])
    task[0]['description'] = request.json.get('description', task[0]['description'])
    task[0]['done'] = request.json.get('done', task[0]['done'])
    return jsonify( { 'task': make_public_task(task[0]) } )
    
@app.route('/todo/api/v1.0/tasks/<int:task_id>', methods = ['DELETE'])
@auth.login_required
def delete_task(task_id):
    task = filter(lambda t: t['id'] == task_id, tasks)
    if len(task) == 0:
        abort(404)
    tasks.remove(task[0])
    return jsonify( { 'result': True } )
    
if __name__ == '__main__':
    app.run(debug = True)

@patilanup246: use the options provided by Postman for HTTP Basic Authentication.

Thanks Miguel, this was very helpful. Just what i was looking for, well explained and easy to understand.

@ineam how to solve that Unicode error ?

@sskanishk You can just replace it with str in python 3+
if 'title' in request.json and type(request.json['title']) != str:
abort(400)
if 'description' in request.json and type(request.json['description']) is not str:
abort(400)

@sskanishk You can just replace it with str in python 3+
if 'title' in request.json and type(request.json['title']) != str:
abort(400)
if 'description' in request.json and type(request.json['description']) is not str:
abort(400)

solved; thanks

Copied the code verbatim. But after curl -u miguel:python -i http://localhost:5000/todo/api/v1.0/tasks
I get the error message:

raise TypeError(repr(o) + " is not JSON serializable")
TypeError: <map object at 0x10a405160> is not JSON serializable

Thank you!
Great tutorial!!

Thank you so much, Miguel, for this wonderful code. Do you happen to have any advice or examples for anyone writing a client for a server like this?

@ronk7 for a JavaScript client I wrote a follow-up tutorial: https://blog.miguelgrinberg.com/post/writing-a-javascript-rest-client. For a Python client use the requests package.

Sorry - what requests package?

…

On Mon, Jul 20, 2020 at 6:15 PM Miguel Grinberg ***@***.***> wrote: ***@***.**** commented on this gist. ------------------------------ @ronk7 <https://github.com/ronk7> for a JavaScript client I wrote a follow-up tutorial: https://blog.miguelgrinberg.com/post/writing-a-javascript-rest-client. For a Python client use the requests package. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <https://gist.github.com/5614326#gistcomment-3384951>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AP7IG5FR2YIJ2BFX2IDZENLR4RNRNANCNFSM4JA3L5XQ> .

@ronk7 pip install requests

Hey @robinvd, I fixed the issue by wrapping map with list:

return jsonify( { 'tasks': list(map(make_public_task, tasks)) } )

And the same happens with filter:

task = list(filter(lambda t: t['id'] == task_id, tasks))

The fixes are needed for Python3.

Hello,Miguel, sorry for my question about it. I'm beginner in flask , true, I'am front-end developer , but i need learn Flask and write Rest server for my task. But i have error while i copy-paste your code.
If a write request curl -i http://localhost:5000/todo/api/v1.0/tasks/2
I getting Error in JSON , why? Can u help me.
See you soon

@CPPtrueCoder What's the error? You don't have any JSON, so what do you mean by "error in JSON"?

When i get curl -i http://localhost:5000/todo/api/v1.0/tasks/2
From server response {
"error": "Not found"
}
but tasks is available :(

@CPPtrueCoder How do you know it is available? What is the response when you send a request to http://localhost:5000/todo/api/v1.0/tasks?

if request : http://localhost:5000/todo/api/v1.0/tasks then tasks like your guide , but then i try request with ID , i have troubles

(venv) C:\Users\a.rodin\PycharmProjects\flaskProject>curl -i http://localhost:5000/todo/api/v1.0/tasks/1
HTTP/1.0 404 NOT FOUND
Content-Type: text/html; charset=utf-8
Content-Length: 232
Server: Werkzeug/1.0.1 Python/3.8.8
Date: Tue, 11 May 2021 10:02:55 GMT

<title>404 Not Found</title>

Not Found

The requested URL was not found on the server. If you entered the URL manually please check your spelling and try again.

i tried rewrite it according updates from comments , but no result , unfortunately

Lol, i changed function :
@app.route('/todo/api/v1.0/tasks/<task_id>', methods=['GET']), instead @app.route('/todo/api/v1.0/tasks/int:task_id', methods=['GET'])
And it's working , but i think it isnt' safely, isn't it ?

@CPPtrueCoder you should use the code as shown above. That is the best. Neither of the two options you posted above matches my code.

Thank you. exactly what i needed as a complete beginner

super useful and straightforward... thanks!!

Thanks, this is helpful, but I do not get the id in the response:

~ curl -u username:password -i http://localhost:5000/todo/api/v1.0/tasks
HTTP/1.0 200 OK
Content-Type: application/json
Content-Length: 407
Server: Werkzeug/2.0.2 Python/3.8.9
Date: Tue, 21 Dec 2021 01:34:46 GMT

{
  "tasks": [
    {
      "description": "Milk, Cheese, Pizza, Fruit, Tylenol",
      "done": false,
      "title": "Buy groceries",
      "uri": "http://localhost:5000/todo/api/v1.0/tasks/1"
    },
    {
      "description": "Need to find a good Python tutorial on the web",
      "done": false,
      "title": "Learn Python",
      "uri": "http://localhost:5000/todo/api/v1.0/tasks/2"
    }
  ]
}

And so I am unable to DELETE it either:

line 102, in delete_task
    if len(task) == 0:
TypeError: object of type 'filter' has no len()

@arafatmohammed you are obviously using different code than what I posted here, so I have no way to tell you what's wrong. Try using my code exactly as shown here.

@miguelgrinberg Thnks for ur great job.
I think you'd better rename this function name to sth better as it conflicts with this function name.
I suggest using def bad_request(error) instead.

Awesome step by step tutorial, Thank you miguel.

Thank you. exactly what i needed as a complete beginner

yeah, right guide.

Не работает ваш код, есть ошибка:
if len(task) == 0:
TypeError: object of type 'filter' has no len()
Нужно преобразовать в список и потом проверять пустой ли он

Can you please help me with multiple parallel requests?
I can call many requests at once but only 5 or 6 are processed at a time.

from flask import Flask
import asyncio
app = Flask(__name__, static_url_path = "")

delaycounter=0
@app.route('/delay')
async def test_route():
    global delaycounter
    print(f"start {delaycounter}")
    delaycounter=delaycounter+1
    await asyncio.sleep(5)
    print(f"end{delaycounter}")
    return "ok"
    
if __name__ == '__main__':
    app.run(debug = True, port=8080)