List Services - NON ASCII limit causes poppy to return 500

[Malini Kamalambal]

Steps to Repro: Run the test https://github.com/stackforge/poppy/blob/master/tests/api/services/test_services.py#L178

Traceback (most recent call last):
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/wsgiref/handlers.py", line 85, in run
    self.result = application(self.environ, self.start_response)
  File "/Users/malini.kamalambal/github/poppyenv/lib/python2.7/site-packages/pecan/middleware/recursive.py", line 56, in __call__
    return self.application(environ, start_response)
  File "/Users/malini.kamalambal/github/poppyenv/lib/python2.7/site-packages/pecan/core.py", line 750, in __call__
    return super(Pecan, self).__call__(environ, start_response)
  File "/Users/malini.kamalambal/github/poppyenv/lib/python2.7/site-packages/pecan/core.py", line 645, in __call__
    e
  File "/Users/malini.kamalambal/github/poppyenv/lib/python2.7/site-packages/pecan/core.py", line 773, in handle_hooks
    return super(Pecan, self).handle_hooks(hooks, *args, **kw)
  File "/Users/malini.kamalambal/github/poppyenv/lib/python2.7/site-packages/pecan/core.py", line 317, in handle_hooks
    result = getattr(hook, hook_type)(*args)
  File "/Users/malini.kamalambal/github/poppy/poppy/transport/pecan/hooks/error.py", line 55, in on_error
    message['message'] = str(exception)
UnicodeEncodeError: 'ascii' codec can't encode characters in position 15-16: ordinal not in range(128)
1.0.0.127.in-addr.arpa - - [22/Oct/2014 10:01:04] "GET /v1.0/services?limit=%E5%AD%A6%E6%A0%A1 HTTP/1.1" 500 59
2014-10-22 10:01:04.026 4340 ERROR poppy.transport.pecan.hooks.error [req-b6f3bb11-0f3c-486d-b8bc-c64d68e0b000 - 650278 - - -] Exception message: Invalid limit:

See test logs,

root: INFO: ========================================================
root: INFO: Test Case....: test_list_services_invalid_limits_6_______
root: INFO: Created At...: 2014-10-22 10:01:03.546432
root: INFO: No Test description.
root: INFO: ========================================================
cafe.engine.http.client: DEBUG: (<tests.api.utils.client.PoppyClient object at 0x101319990>, 'GET', 'http://0.0.0.0:8888/v1.0/services') {'headers': {'Content-Type': 'application/json', 'X-Project-Id': u'650278', 'X-Auth-Token': u'6f2a4ebe6f3a438d89422fde3dc05d82'}, 'params': {'limit': '\xe5\xad\xa6\xe6\xa0\xa1'}, 'verify': False, 'data': None}
requests.packages.urllib3.connectionpool: INFO: Starting new HTTP connection (1): 0.0.0.0
requests.packages.urllib3.connectionpool: DEBUG: "GET /v1.0/services?limit=%E5%AD%A6%E6%A0%A1 HTTP/1.1" 500 59
cafe.engine.http.client: DEBUG:
------------
REQUEST SENT
------------
request method..: GET
request url.....: http://0.0.0.0:8888/v1.0/services
request params..: limit=%E5%AD%A6%E6%A0%A1
request headers.: {'Accept-Encoding': 'gzip, deflate', 'X-Project-Id': u'650278', 'Accept': '*/*', 'X-Auth-Token': u'6f2a4ebe6f3a438d89422fde3dc05d82', 'Connection': 'keep-alive', 'User-Agent': 'python-requests/2.4.1 CPython/2.7.1 Darwin/11.4.2', 'Content-Type': 'application/json'}
request body....: None

cafe.engine.http.client: DEBUG:
-----------------
RESPONSE RECEIVED
-----------------
response status..: <Response [500]>
response time....: 0.00837707519531
response headers.: {'date': 'Wed, 22 Oct 2014 14:01:04 GMT', 'content-length': '59', 'content-type': 'text/plain', 'server': 'WSGIServer/0.1 Python/2.7.1'}
response body....: A server error occurred. Please contact the administrator.