Werkzeug LintMiddleware w/Flask

flask_issue.py

# Pretty much lifted from https://github.com/pallets/flask/issues/2992
#
# To test:
# $ export FLASK_APP=flask_issue.py 
# $ python -m flask run
# $ curl -v http://127.0.0.1:5000/streamingerror
# Notice how respose is 200 but still truncated

from flask import Flask, Response
from werkzeug.middleware.lint import LintMiddleware

app = Flask(__name__)

# Wire LintMiddleware
app.wsgi_app = LintMiddleware(app.wsgi_app)

@app.route('/')
def default_route():
    return 'hello world'

@app.route('/error')
def error_route():
    raise Exception('error in error_route')

@app.route('/streamingerror')
def streaming_error_route():
    def inner_gen():
        yield 'hello'
        raise Exception('error from streaming_error_route')
        yield 'bye'
    return Response(inner_gen())

@app.errorhandler(Exception)
def custom_exception_handler(_):
    return 'handled by custom exception handler'