Python flask DELETE request

Question

I'm in the middle of developing a Python app and using flask, and this is my DELETE function:

@app.route('/DeleteMessage', methods=['DELETE'])
def DeleteMessage():
    messages = Message.query.all()
    application_id = request.args.get('application_id')
    if application_id:
        messages.filter_by(user_id=application_id)
    session_id = request.args.get('session_id')
    if session_id:
        messages.filter_by(session_id=session_id)    
    message_id = request.args.get('message_id')
    if message_id:
        messages = message.filter_by(message_id=message_id)  
    db.session.delete(messages)
    db.session.commit()
    return 'ok'

When I try to run it, it sends me such an error message:

Method Not Allowed
The method is not allowed for the requested URL.

If you're just typing that into the address bar, that's a GET request. — snakecharmerb, Apr 29 '20 at 17:08
How are you sending the request? From javascript? Are you setting the delete http method type? — jignatius, Apr 29 '20 at 17:15
I'm only developing the server side, so I'm currently running this function by typing: http://127.0.0.1:5000/DeleteMessage?applicationId=1 Into the search bar in my browser — toffee, Apr 29 '20 at 17:22

NavaneethaKrishnan · Answer 1 · 2020-04-29T18:48:53.493

2

Browsers support PUT and DELETE only with AJAX request, but not with HTML form submission. HTML form tag will allow only GET and POST methods.

In your case, you can send an ajax request like this,

$.ajax({
url: '{{url_for("DeleteMessage")}}',
type: 'DELETE',
success: function(result) {
    // write something if needed
}
});

edited Apr 29 '20 at 18:48

answered Apr 29 '20 at 18:37

NavaneethaKrishnan

1,213
1
9
22

score 1 · Answer 2 · edited Oct 07 '21 at 13:39

1

You make GET request, but your flask backend awaiting DELETE request on that endpoint /DeleteMessage. You can change request method to GET @app.route('/DeleteMessage', methods=['GET']) and it will work, but it is contrary to the http standard.

You can read about how to send DELETE request in this question: How to send DELETE request?

Additional Information:

https://www.rfc-editor.org/rfc/rfc2616#section-9.3 https://www.restapitutorial.com/lessons/httpmethods.html

edited Oct 07 '21 at 13:39

Community

1
1

answered Apr 29 '20 at 18:48

Mikhail Sidorov

1,325
11
15

I tried: @ app.route ('/ DeleteMessage', methods = ['GET']) But I received such an error message: sqlalchemy.orm.exc.UnmappedInstanceError: Class 'flask_sqlalchemy.BaseQuery' is not mapped – toffee Apr 29 '20 at 21:46
Please, update the question and include code for your models and db engine. – Mikhail Sidorov Apr 29 '20 at 21:48

Python flask DELETE request

2 Answers2

Linked

Related