We’re using Flask for one of our API’s and I was just wondering if anyone knew how to return a HTTP response 201?

For errors such as 404 we can call:

from flask import abort
abort(404)

But for 201 I get

LookupError: no exception for 201

Do I need to create my own exception like this in the docs?

You can read about it here.

return render_template('page.html'), 201

You can use Response to return any http status code.

> from flask import Response
> return Response("{'a':'b'}", status=201, mimetype='application/json')

As lacks suggested send status code in return statement and if you are storing it in some variable like

notfound = 404
invalid = 403
ok = 200

and using

return xyz, notfound

than time make sure its type is int not str. as I faced this small issue also here is list of status code followed globally http://www.w3.org/Protocols/HTTP/HTRESP.html

Hope it helps.

You can do

result = {'a': 'b'}
return jsonify(result), 201

if you want to return a JSON data in the response along with the error code You can read about responses here and here for make_response API details

In your flask code, you should ideally specify the MIME type as often as possible, as well:

return html_page_str, 200, {'ContentType':'text/html'}

return json.dumps({'success':True}), 200, {'ContentType':'application/json'}

…etc

you can also use flask_api for sending response

from flask_api import status

@app.route('/your-api/')
def empty_view(self):
    content = {'your content here'}
    return content, status.HTTP_201_CREATED

you can find reference here http://www.flaskapi.org/api-guide/status-codes/

Dependent on how the API is created, normally with a 201 (created) you would return the resource which was created. For example if it was creating a user account you would do something like:

return {"data": {"username": "test","id":"fdsf345"}}, 201

Note the postfixed number is the status code returned.

Alternatively, you may want to send a message to the client such as:

return {"msg": "Created Successfully"}, 201

In my case I had to combine the above in order to make it work

return Response(json.dumps({'Error': 'Error in payload'}), 
status=422, 
mimetype="application/json")

So, if you are using flask_restful Package for API’s returning 201 would becomes like

def bla(*args, **kwargs):
    ...
    return data, 201

where data should be any hashable/ JsonSerialiable value, like dict, string.