How do you get a query string on Flask?

from flask import request

@app.route('/data')
def data():
    # here we want to get the value of user (i.e. ?user=some-value)
    user = request.args.get('user')

The full URL is available as request.url, and the query string is available as request.query_string.decode().

Here's an example:

from flask import request

@app.route('/adhoc_test/')
def adhoc_test():

    return request.query_string

To access an individual known param passed in the query string, you can use request.args.get('param'). This is the "right" way to do it, as far as I know.

ETA: Before you go further, you should ask yourself why you want the query string. I've never had to pull in the raw string - Flask has mechanisms for accessing it in an abstracted way. You should use those unless you have a compelling reason not to.


I came here looking for the query string, not how to get values from the query string.

request.query_string returns the URL parameters as raw byte string (Ref 1).

Example of using request.query_string:

from flask import Flask, request

app = Flask(__name__)

@app.route('/data', methods=['GET'])
def get_query_string():
    return request.query_string

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

Output:

query parameters in Flask route

References:

  1. Official API documentation on query_string