Fix: Any invalid message in a response crashed the entire response

The code serving the API may return messages that are not valid according the latest version of the schemas. Ignore them with an optional log instead of failing the parsing of the entire response.

src/aleph_client/asynchronous.py

@@ -24,11 +24,12 @@
     AggregateMessage,
     StoreMessage,
     ProgramMessage,
-    MessagesResponse,
 )
+from pydantic import ValidationError
 
 from aleph_client.types import Account, StorageEnum, GenericMessage
 from .exceptions import MessageNotFoundError, MultipleMessagesError
+from .models import MessagesResponse
 from .utils import get_message_type_value
 
 logger = logging.getLogger(__name__)
@@ -576,6 +577,8 @@ async def get_messages(
     end_date: Optional[Union[datetime, float]] = None,
     session: Optional[ClientSession] = None,
     api_server: str = settings.API_HOST,
+    ignore_invalid_messages: bool = True,
+    invalid_messages_log_level: int = logging.NOTSET,
 ) -> MessagesResponse:
     session = session or get_fallback_session()
 
@@ -611,8 +614,36 @@ async def get_messages(
 
     async with session.get(f"{api_server}/api/v0/messages.json", params=params) as resp:
         resp.raise_for_status()
-        messages_json = await resp.json()
-        return MessagesResponse(**messages_json)
+        response_json = await resp.json()
+        messages_raw = response_json["messages"]
+
+        # All messages may not be valid according to the latest specification in
+        # aleph-message. This allows the user to specify how errors should be handled.
+        messages: List[AlephMessage] = []
+        for message_raw in messages_raw:
+            try:
+                message = Message(**message_raw)
+                messages.append(message)
+            except KeyError as e:
+                if not ignore_invalid_messages:
+                    raise e
+                logger.log(
+                    level=invalid_messages_log_level,
+                    msg=f"KeyError: Field '{e.args[0]}' not found",
+                )
+            except ValidationError as e:
+                if not ignore_invalid_messages:
+                    raise e
+                if invalid_messages_log_level:
+                    logger.log(level=invalid_messages_log_level, msg=e)
+
+        return MessagesResponse(
+            messages=messages,
+            pagination_page=response_json["pagination_page"],
+            pagination_total=response_json["pagination_total"],
+            pagination_per_page=response_json["pagination_per_page"],
+            pagination_item=response_json["pagination_item"],
+        )
 
 
 async def get_message(

src/aleph_client/models.py

@@ -0,0 +1,14 @@
+from typing import List
+
+from aleph_message.models import AlephMessage
+from pydantic import BaseModel
+
+
+class MessagesResponse(BaseModel):
+    """Response from an Aleph node API on the path /api/v0/messages.json"""
+
+    messages: List[AlephMessage]
+    pagination_page: int
+    pagination_total: int
+    pagination_per_page: int
+    pagination_item: str