Running Kinto with provided app.wsgi does not remove SCRIPT_NAME from URL

[dstaley]

I'm currently working on running Kinto on AWS Lambda, using the provided app.wsgi file to load Kinto.

My Kinto instance is deployed at a URL containing a prefix, https://api.gateway.amazon/dev/v1.

When translating Lambda events to WSGI environment parameters, I'm setting SCRIPT_NAME to /dev, and PATH_INFO to /v1. If I do this, Kinto complains that /dev/v1 is not a valid route. If I explicitly remove SCRIPT_NAME from the environment variables before calling the app, it works fine.

I believe this is due to Pyramid/Waitress combining the SCRIPT_NAME and PATH_INFO when passing the URL to Kinto. I'm doing some research into how this can be disabled (and if this is even the cause), and I'll send a PR if I find the appropriate config option.

Here's a short reproduction:

import os
import sys
from werkzeug.wrappers import Response
from werkzeug._compat import (BytesIO, to_bytes)
import configparser
import logging.config

from kinto import main


here = os.path.dirname(__file__)

ini_path = os.path.join(here, 'config', 'kinto.ini')

# Set up logging
logging.config.fileConfig(ini_path)

# Parse config and create WSGI app
config = configparser.ConfigParser()
config.read(ini_path)

application = main(config.items('DEFAULT'), **dict(config.items('app:main')))

body = to_bytes(
    '{"data": {"description": "Write a tutorial explaining Kinto", "status": "todo"}}\n',
    charset='utf-8'
)

environ = {
    'CONTENT_LENGTH': str(len(body)),
    'CONTENT_TYPE': 'application/json',
    'PATH_INFO': '/v1/buckets/default/collections/tasks/records',
    'QUERY_STRING': {},
    'REMOTE_ADDR': '',
    'REMOTE_USER': '',
    'REQUEST_METHOD': 'POST',
    'SCRIPT_NAME': '/dev',
    'SERVER_NAME': 'oggaoggabooga.execute-api.us-east-1.amazonaws.com',
    'SERVER_PORT': '443',
    'SERVER_PROTOCOL': 'HTTP/1.1',
    'wsgi.errors': sys.stderr,
    'wsgi.input': BytesIO(body),
    'wsgi.multiprocess': False,
    'wsgi.multithread': False,
    'wsgi.run_once': False,
    'wsgi.url_scheme': 'https',
    'wsgi.version': (1, 0),
    'HTTP_AUTHORIZATION': 'Basic ZHN0YWxleTpwYXNzd29yZA==',
    'HTTP_CONTENT_TYPE': 'application/json',
    'HTTP_HOST': 'oggaoggabooga.execute-api.us-east-1.amazonaws.com',
}

response = Response.from_app(application, environ)

print(response.status_code)

This is the error I'm getting:

"POST  /dev/v1/buckets/default/collections/tasks/records?" ? (? ms) URI has no route errno=999
Traceback (most recent call last):
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/pyramid/tweens.py", line 39, in excview_tween
    response = handler(request)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/kinto/core/events.py", line 76, in tween
    response = handler(request)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/pyramid/router.py", line 156, in handle_request
    view_name
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/pyramid/view.py", line 642, in _call_view
    response = view_callable(context, request)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/pyramid/viewderivers.py", line 410, in viewresult_to_response
    result = view(context, request)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/pyramid/viewderivers.py", line 148, in _requestonly_view
    response = view(request)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/kinto/plugins/default_bucket/__init__.py", line 145, in default_bucket
    create_bucket(request, bucket_id)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/kinto/plugins/default_bucket/__init__.py", line 35, in create_bucket
    uri=bucket_uri)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/kinto/plugins/default_bucket/__init__.py", line 79, in resource_create_object
    resource_name, matchdict = view_lookup(request, uri)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/kinto/core/utils.py", line 448, in view_lookup
    return view_lookup_registry(request.registry, uri)
  File "/Users/dylanstaley/Desktop/kinto-wsgi/.venv/lib/python3.6/site-packages/kinto/core/utils.py", line 472, in view_lookup_registry
    raise ValueError('URI has no route')

Changing the SCRIPT_NAME attribute to '' eliminates the error.

[leplatrem]

@dstaley Do you have suggestion for this?

[Natim]

Do you need SCRIPT_NAME for anything or is it a sufficient fix to change it into an empty string?

[dstaley]

The reproduction that manually specifies the WSGI variables was just to demonstrate the error. In a proper WSGI environment, SCRIPT_NAME is set by the web server. I imagine this would be an issue for any WSGI host that has Kinto at a non-root level.