fix: handle the payloads and endpoints the REST unit specifications exercise

Nine faults the derived suite found, each of which raised where an error
should have been returned or a value parsed:

- a present-but-null `encoding` reached `EncodeDataMixin.decode` as None,
  raising AttributeError for messages, presence messages and annotations
- `TokenDetails.from_json` mutated the dict it was iterating, and rejected
  wire fields the constructor does not model
- `format_params` compared a stringified `limit` against an integer
- a 204 carries no Content-Type, which `PaginatedResult` subscripted
- an IPv6 endpoint produced `https://::1:443`, which httpx rejects
- an undecodable content type on a 2xx surfaced as 50000 rather than 40013
- an error body carrying `error` as a string raised TypeError
- `Http.http_max_retry_count` had no entry to fall back to
- a JSON auth_url response was taken to be a TokenDetails only when it
  carried `issued`, so a payload with `token` alone was rejected as 40170

Each is reachable through the public API and independent of the derived
suite, which arrives later in this stack and covers all nine.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: owenpearson

ably/http/http.py

@@ -104,7 +104,7 @@ def to_native(self):
             elif content_type.startswith('application/json'):
                 return self.__response.json()
 
-        raise ValueError("Unsupported content type")
+        raise AblyException("Unsupported content type", 400, 40013)
 
     @property
     def response(self):
@@ -118,6 +118,7 @@ class Http:
     CONNECTION_RETRY_DEFAULTS = {
         'http_open_timeout': 4,
         'http_request_timeout': 10,
+        'http_max_retry_count': 3,
         'http_max_retry_duration': 15,
     }
 
@@ -200,7 +201,7 @@ def should_stop_retrying(retry_count=retry_count):
                 # if it's the last try or cumulative timeout is done, we stop retrying
                 return retry_count == len(hosts) - 1 or time_passed > http_max_retry_duration
 
-            base_url = f"{self.preferred_scheme}://{host}:{self.preferred_port}"
+            base_url = f"{self.preferred_scheme}://{HttpUtils.host_for_url(host)}:{self.preferred_port}"
             url = urljoin(base_url, path)
 
             (clean_url, url_params) = extract_url_params(url)

ably/http/httputils.py

@@ -1,4 +1,5 @@
 import base64
+import ipaddress
 import os
 import platform
 
@@ -30,6 +31,19 @@ def default_post_headers(binary=False, version=None):
         headers["Content-Type"] = headers["Accept"]
         return headers
 
+    @staticmethod
+    def host_for_url(host):
+        """Renders a host for inclusion in a URL.
+
+        An IPv6 literal is bracketed so that its colons are not read as a port
+        separator; every other form of host is returned unchanged.
+        """
+        try:
+            is_ipv6 = ipaddress.ip_address(host).version == 6
+        except ValueError:
+            is_ipv6 = False
+        return f'[{host}]' if is_ipv6 else host
+
     @staticmethod
     def get_host_header(host):
         return {

ably/http/paginatedresult.py

@@ -31,6 +31,7 @@ def format_params(params=None, direction=None, start=None, end=None, limit=None,
     if end:
         params['end'] = format_time_param(end)
     if limit:
+        limit = int(limit)
         if limit > 1000:
             raise ValueError("The maximum allowed limit is 1000")
         params['limit'] = f'{limit}'
@@ -95,7 +96,7 @@ async def paginated_query_with_request(cls, http, request, response_processor,
 
         items = response_processor(response)
 
-        content_type = response.headers['Content-Type']
+        content_type = response.headers.get('Content-Type')
         links = response.links
         if 'first' in links:
             first_rel_request = request.with_relative_url(links['first']['url'])

ably/rest/auth.py

@@ -200,7 +200,7 @@ async def request_token(self, token_params: dict | None = None,
             raise AblyAuthException(msg, 403, 40171)
         if isinstance(token_request, TokenDetails):
             return token_request
-        elif isinstance(token_request, dict) and 'issued' in token_request:
+        elif isinstance(token_request, dict) and ('issued' in token_request or 'token' in token_request):
             return TokenDetails.from_dict(token_request)
         elif isinstance(token_request, dict):
             try:

ably/types/annotation.py

@@ -208,7 +208,7 @@ def from_encoded(obj, cipher=None, context=None):
         name = obj.get('name')
         count = obj.get('count')
         data = obj.get('data')
-        encoding = obj.get('encoding', '')
+        encoding = obj.get('encoding') or ''
         id = obj.get('id')
         client_id = obj.get('clientId')
         connection_id = obj.get('connectionId')

ably/types/message.py

@@ -293,7 +293,7 @@ def from_encoded(obj, cipher=None, context=None):
         client_id = obj.get('clientId')
         connection_id = obj.get('connectionId')
         timestamp = obj.get('timestamp')
-        encoding = obj.get('encoding', '')
+        encoding = obj.get('encoding') or ''
         extras = obj.get('extras', None)
         serial = obj.get('serial')
         action = obj.get('action')

ably/types/presence.py

@@ -175,7 +175,7 @@ def from_encoded(obj, cipher=None, context=None):
         client_id = obj.get('clientId')
         connection_id = obj.get('connectionId')
         data = obj.get('data')
-        encoding = obj.get('encoding', '')
+        encoding = obj.get('encoding') or ''
         timestamp = obj.get('timestamp')
         # member_key = obj.get('memberKey', None)
         extras = obj.get('extras', None)

ably/types/tokendetails.py

@@ -71,15 +71,7 @@ def from_json(data):
         if isinstance(data, str):
             data = json.loads(data)
 
-        mapping = {
-            'clientId': 'client_id',
-        }
-        for name in data:
-            py_name = mapping.get(name)
-            if py_name:
-                data[py_name] = data.pop(name)
-
-        return TokenDetails(**data)
+        return TokenDetails.from_dict(data)
 
     def __eq__(self, other):
         if isinstance(other, TokenDetails):

ably/util/exceptions.py

@@ -53,7 +53,7 @@ def raise_for_response(response):
                     status_code=error['statusCode'],
                     code=int(error['code']),
                 )
-            except KeyError:
+            except (KeyError, TypeError):
                 msg = "Unexpected exception decoding server response: %s"
                 msg = msg % response.text
                 raise AblyException(message=msg, status_code=500, code=50000) from None

test/ably/rest/resthttp_test.py

@@ -10,6 +10,7 @@
 from httpx import Response
 
 from ably import AblyRest
+from ably.http.httputils import HttpUtils
 from ably.transport.defaults import Defaults
 from ably.types.options import Options
 from ably.util.exceptions import AblyException
@@ -18,6 +19,15 @@
 
 
 class TestRestHttp(BaseAsyncTestCase):
+    async def test_host_for_url_brackets_only_ipv6_literals(self):
+        assert HttpUtils.host_for_url('::1') == '[::1]'
+        assert HttpUtils.host_for_url('2001:db8::1') == '[2001:db8::1]'
+
+        # A colon alone does not make a host an IPv6 literal
+        assert HttpUtils.host_for_url('rest.ably.io') == 'rest.ably.io'
+        assert HttpUtils.host_for_url('https://www.google.com') == 'https://www.google.com'
+        assert HttpUtils.host_for_url('[::1]') == '[::1]'
+
     async def test_max_retry_attempts_and_timeouts_defaults(self):
         ably = AblyRest(token="foo")
         assert 'http_open_timeout' in ably.http.CONNECTION_RETRY_DEFAULTS