JSONP in Flask

jsonp-in-flask.py

from functools import wraps
from flask import request, current_app, jsonify, Flask

app = Flask(__name__)


def jsonp(f):
    """Wraps JSONified output for JSONP"""

    @wraps(f)
    def decorated_function(*args, **kwargs):
        callback = request.args.get('callback', None)
        rtn = f(*args, **kwargs)
        if isinstance(rtn, tuple):
            content = '{0}({1})'.format(str(callback), rtn[0].data) if callback else rtn[0].data
            status = rtn[1]
        else:
            content = '{0}({1})'.format(str(callback), rtn.data) if callback else rtn.data
            status = 200
        return current_app.response_class(content, mimetype='application/javascript', status=status)

    return decorated_function


# then in your view
@app.route('/test', methods=['GET'])
@jsonp
def test():
    return jsonify({"foo": "bar"})


if __name__ == "__main__":
    app.run()

at python3.6

            content = '{0}({1})'.format(str(callback), rtn.data) if callback else rtn.data

should be

            content = '{0}({1})'.format(str(callback), eval(rtn.data)) if callback else rtn.data