3173ab4c4b
This changeset reimplements the API using Pecan and WSME instead of Flask. Pecan uses "object dispatch" instead of declared routes. The controller classes are chained together to implement the API. Most of what we have are simple REST lookups, but a few cases required custom methods. WSME is used to define types of inputs and outputs for each controller method. The WSME layer handles serizlization and deserialization in several formats. In our case, only JSON and XML are configured. There are a few small changes to the return types in the API, as well as to error handling. Now all errors are returned as JSON messages made up of a mapping containing the key 'error_message' and the text of the error. This will later be enhanced to include XML support for XML requests. This change also moves the script for starting the V1 API to a new name and replaces it with a script that starts the V2 API. There is an open bug/blueprint to fix that so both versions of the API are loaded. blueprint api-server-pecan-wsme Signed-off-by: Doug Hellmann <doug.hellmann@dreamhost.com> Change-Id: I1b99a16de68f902370a8999eca073c56f9f14865
75 lines
2.9 KiB
Python
75 lines
2.9 KiB
Python
# -*- encoding: utf-8 -*-
|
|
#
|
|
# Copyright © 2012 New Dream Network, LLC (DreamHost)
|
|
#
|
|
# Author: Doug Hellmann <doug.hellmann@dreamhost.com>
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License"); you may
|
|
# not use this file except in compliance with the License. You may obtain
|
|
# a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
# License for the specific language governing permissions and limitations
|
|
# under the License.
|
|
"""Middleware to replace the plain text message body of an error
|
|
response with one formatted so the client can parse it.
|
|
|
|
Based on pecan.middleware.errordocument
|
|
"""
|
|
|
|
import json
|
|
|
|
from webob import exc
|
|
|
|
|
|
class ParsableErrorMiddleware(object):
|
|
"""Replace error body with something the client can parse.
|
|
"""
|
|
def __init__(self, app):
|
|
self.app = app
|
|
|
|
def __call__(self, environ, start_response):
|
|
# Request for this state, modified by replace_start_response()
|
|
# and used when an error is being reported.
|
|
state = {}
|
|
|
|
def replacement_start_response(status, headers, exc_info=None):
|
|
"""Overrides the default response to make errors parsable.
|
|
"""
|
|
try:
|
|
status_code = int(status.split(' ')[0])
|
|
state['status_code'] = status_code
|
|
except (ValueError, TypeError): # pragma: nocover
|
|
raise Exception((
|
|
'ErrorDocumentMiddleware received an invalid '
|
|
'status %s' % status
|
|
))
|
|
else:
|
|
if (state['status_code'] / 100) not in (2, 3):
|
|
# Remove some headers so we can replace them later
|
|
# when we have the full error message and can
|
|
# compute the length.
|
|
headers = [(h, v)
|
|
for (h, v) in headers
|
|
if h not in ('Content-Length', 'Content-Type')
|
|
]
|
|
# Save the headers in case we need to modify them.
|
|
state['headers'] = headers
|
|
return start_response(status, headers, exc_info)
|
|
|
|
app_iter = self.app(environ, replacement_start_response)
|
|
if (state['status_code'] / 100) not in (2, 3):
|
|
# FIXME(dhellmann): Always returns errors as JSON,
|
|
# but should look at the environ to determine
|
|
# the desired type.
|
|
body = [json.dumps({'error_message': '\n'.join(app_iter)})]
|
|
state['headers'].append(('Content-Length', len(body[0])))
|
|
state['headers'].append(('Content-Type', 'application/json'))
|
|
else:
|
|
body = app_iter
|
|
return body
|