How to get POSTed json in Flask?

This is the way I would do it and it should be

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.get_json(silent=True)
    print content
    return uuid

With silent=True set, the get_json function will fail silently when trying to retrieve the json body. By default this is set to False. Setting force=True will ignore the request.headers.get('Content-Type') == 'application/json' check that flask does for you. By default this is also set to False. See flask documentation.

I would strongly recommend leaving force=False and make the client send the Content-Type header to make it more explicit.

Hope this helps!

For reference, here's complete code for how to send json from a Python client:

import requests
res = requests.post('http://localhost:5000/api/add_message/1234', json={"mytext":"lalala"})
if res.ok:
    print res.json()

The "json=" input will automatically set the content-type, as discussed here: Post JSON using Python Requests

And the above client will work with this server-side code:

from flask import Flask, request, jsonify
app = Flask(__name__)

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.json
    print content['mytext']
    return jsonify({"uuid":uuid})

if __name__ == '__main__':
    app.run(host= '0.0.0.0',debug=True)

This solution works:

from flask import Flask, request, jsonify

app = Flask(__name__)


@app.route('/hello', methods=['POST'])
def hello():
   return jsonify(request.json)