Large JSON is truncated for over 1MB in Flask

[debugsoul]

I am not sure this is a bug or I am missing something, I see several blogs I don't find anything at all and all these objects being accepted for any size in .net core as well in Node but when I tried with flask it's not accepting large size of the JSON object. I don't think MAX_CONTENT_LENGTH is playing any roles in this. FYI I am not trying to upload a file, I just want to pass large JSON Object over the server, I tried in both Dev vs Prod mode same behavior.

Expected Behavior

This should accept all the content from the JSON Objects.

I was using the following JSON as well with larger it's accepting until 1.1MB over it will get truncated and the request was made from the angular application.

(https://github.com/pallets/flask/files/4183314/accepted.txt) -- successfully received. 
(https://github.com/pallets/flask/files/4183315/rejected.txt)  -- rejected

Actual Behavior

 The object being truncated after 1mb size. 

Startup

from flask import Flask, render_template, Blueprint

from flask_cors import CORS


def create_app():
    app = Flask(__name__)
    CORS(app, resources={r"/api/*": {"origins": "*"}})
    app.config['SECRET_KEY'] = "secret!"
    app.config['DEBUG'] = False
    app.config['MAX_CONTENT_LENGTH'] = 1600 * 1024 * 1024
    app.register_blueprint(bp)

    return app

obj = create_app()

if __name__ == '__main__':
    obj.run()

Blueprint

from flask import Blueprint, request

bp = Blueprint('bp', __name__, url_prefix='/image')

@bp.route('PostImage', methods=['POST'])
def PostImage():
    print(request.data)
    print('text')
    return 'test', 200

Environment

• Python version: 3.6

• Flask version: 1.1.1

• Werkzeug version: 1.0.0

[davidism]

There is nothing in Flask that will truncate large responses. Try checking your server configuration.