run_dev_server swallows falcon.HTTPError and returns 500

[lmergner]

I've been trying out updraft. werkzeug server to swallow falcon's error handling and reraise it as a 500 error.

import falcon
from marshmallow.exceptions import ValidationError
from marshmallow import Schema, fields
from updraft.dev_server import run_dev_server
import logging

logger = logging.getLogger(__name__)


class ErrorSchema(Schema):
    oid = fields.Int(dump_only=True)
    text = fields.Str(required=True)


class Error(object):
    # TODO: Implement

    def on_get(self, req, resp):
        try:
            ErrorSchema().load({"blarg": "Should raise an exception"})
        except ValidationError as e:
            logger.exception(e)
            raise falcon.HTTPBadRequest()


api = falcon.API()
api.add_route("/", Error())
run_dev_server(api, hostname="0.0.0.0", port=5000, use_reloader=True)

Example output

(publicity-zhV7bCdV) lmerg@mergner-darwin in publicity $ http http://localhost:5000/
HTTP/1.0 500 Internal Server Error
Date: Sun, 14 Oct 2018 00:11:48 GMT
Server: BaseHTTP/0.6 Python/3.7.0
content-length: 971
content-type: application/json; charset=UTF-8
vary: Accept

{
    "description": "Traceback (most recent call last):\n  File \"handle.py\", line 23, in on_get\n    ErrorSchema().load({\"blarg\": \"Should raise an exception\"})\n  File \"/Users/lmerg/code/.virtualenvs/publicity-zhV7bCdV/lib/python3.7/site-packages/marshmallow/schema.py\", line 529, in load\n    postprocess=True,\n  File \"/Users/lmerg/code/.virtualenvs/publicity-zhV7bCdV/lib/python3.7/site-packages/marshmallow/schema.py\", line 682, in _do_load\n    raise exc\nmarshmallow.exceptions.ValidationError: {'text': ['Missing data for required field.'], 'blarg': ['Unknown field.']}\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n  File \"/Users/lmerg/code/contrivers/publicity/falcon/falcon/api.py\", line 247, in __call__\n    responder(req, resp, **params)\n  File \"handle.py\", line 28, in on_get\n    raise falcon.HTTPBadRequest()\nfalcon.errors.HTTPBadRequest\n",
    "title": "500 Internal Server Error"
}

Example expected output (with gunicorn)

(venv) $ http http://localhost:5000/
HTTP/1.1 400 Bad Request
Connection: close
Date: Sun, 14 Oct 2018 00:18:53 GMT
Server: gunicorn/19.9.0
content-length: 28
content-type: application/json; charset=UTF-8
vary: Accept

{
    "title": "400 Bad Request"
}