Fix best_match() deprecation warning

wsgi call to best_match() generates the following warning:

DeprecationWarning: The behavior of AcceptValidHeader.best_match
is currently being maintained for backward compatibility, but it
will be deprecated in the future, as it does not conform to the RFC.

Change to use acceptable_offers() as was done in nova code.

Simlar changes in the wsgi best language code as well, except
new call is to lookup().

Required bump to get WebOb 1.8.2.

Trivialfix

Change-Id: I45a222c098658eef6a49adcc168b0f5625ea49db

lower-constraints.txt

@@ -147,6 +147,6 @@ unittest2==1.1.0
 vine==1.1.4
 waitress==1.1.0
 weakrefmethod==1.0.2
-WebOb==1.7.1
+WebOb==1.8.2
 WebTest==2.0.27
 wrapt==1.7.0

neutron/pecan_wsgi/hooks/translation.py

@@ -28,8 +28,11 @@ class ExceptionTranslationHook(hooks.PecanHook):
     def on_error(self, state, e):
         language = None
         if state.request.accept_language:
-            language = state.request.accept_language.best_match(
-                oslo_i18n.get_available_languages('neutron'))
+            all_languages = oslo_i18n.get_available_languages('neutron')
+            language = state.request.accept_language.lookup(all_languages,
+                default='fake_LANG')
+            if language == 'fake_LANG':
+                language = None
         exc = api_common.convert_exception_to_http_exc(e, faults.FAULT_MAP,
                                                        language)
         if hasattr(exc, 'code') and 400 <= exc.code < 500:

neutron/wsgi.py

@@ -249,8 +249,10 @@ class Request(wsgi.Request):
         ctypes = ['application/json']
 
         # Finally search in Accept-* headers
-        bm = self.accept.best_match(ctypes)
-        return bm or 'application/json'
+        acceptable = self.accept.acceptable_offers(ctypes)
+        if acceptable:
+            return acceptable[0][0]
+        return 'application/json'
 
     def get_content_type(self):
         allowed_types = ("application/json",)
@@ -271,7 +273,11 @@ class Request(wsgi.Request):
         if not self.accept_language:
             return None
         all_languages = oslo_i18n.get_available_languages('neutron')
-        return self.accept_language.best_match(all_languages)
+        best_match = self.accept_language.lookup(all_languages,
+                                                 default='fake_LANG')
+        if best_match == 'fake_LANG':
+            best_match = None
+        return best_match
 
     @property
     def context(self):

requirements.txt

@@ -20,7 +20,7 @@ python-neutronclient>=6.7.0 # Apache-2.0
 tenacity>=3.2.1 # Apache-2.0
 ryu>=4.24 # Apache-2.0
 SQLAlchemy!=1.1.5,!=1.1.6,!=1.1.7,!=1.1.8,>=1.2.0 # MIT
-WebOb>=1.7.1 # MIT
+WebOb>=1.8.2 # MIT
 keystoneauth1>=3.4.0 # Apache-2.0
 alembic>=0.8.10 # MIT
 six>=1.10.0 # MIT