Get the data received in a Flask request
flask, python, werkzeug
Solution
The docs describe the attributes available on the `request` object (`from flask import request`) during a request. In most common cases `request.data` will be empty because it's used as a fallback:
`request.data` Contains the incoming request data as string in case it came with a mimetype Flask does not handle.
- `request.args`: the key/value pairs in the URL query string
- `request.form`: the key/value pairs in the body, from a HTML post form, or JavaScript request that isn't JSON encoded
- `request.files`: the files in the body, which Flask keeps separate from `form`. HTML forms must use `enctype=multipart/form-data` or files will not be uploaded.
- `request.values`: combined `args` and `form`, preferring `args` if keys overlap
- `request.json`: parsed JSON data. The request must have the `application/json` content type, or use `request.get_json(force=True)` to ignore the content type.
All of these are `MultiDict` instances (except for `json`). You can access values using:
- `request.form['name']`: use indexing if you know the key exists
- `request.form.get('name')`: use `get` if the key might not exist
- `request.form.getlist('name')`: use `getlist` if the key is sent multiple times and you want a list of values. `get` only returns the first value.
Problem
I want to be able to get the data sent to my Flask app. I've tried accessing `request.data` but it is an empty string. How do you access request data? ``` from flask import request @app.route('/', methods=['GET', 'POST']) def parse_request(): data = request.data # data is empty # need posted data here ``` The answer to this question led me to ask Get raw POST body in Python Flask regardless of Content-Type header next, which is about getting the raw data rather than the parsed data.