CV2-4952: ClassyCat Error Handling and Metrics

lib/base_exception.py

@@ -0,0 +1,8 @@
+class PrestoBaseException(Exception):
+    def __init__(self, message: str, error_code: int = 500):
+        self.message = message
+        self.error_code = error_code
+        super().__init__(message)
+
+    def __str__(self):
+        return f"{self.error_code}: {self.message}"

lib/model/classycat.py

@@ -5,6 +5,7 @@
 from lib.model.classycat_classify import Model as ClassifyModel
 from lib.model.classycat_schema_create import Model as ClassyCatSchemaCreateModel
 from lib.model.classycat_schema_lookup import Model as ClassyCatSchemaLookupModel
+from lib.base_exception import PrestoBaseException
 
 
 class Model(Model):
@@ -21,5 +22,4 @@ def process(self, message: Message) -> Union[ClassyCatSchemaResponse, ClassyCatB
             return ClassyCatSchemaCreateModel().process(message)
         else:
             logger.error(f"Unknown event type {event_type}")
-            message.body.result.responseMessage = f"Unknown event type {event_type}"
-            return message.body.result
+            raise PrestoBaseException(f"Unknown event type {event_type}", 422)

lib/model/classycat_classify.py

@@ -8,6 +8,7 @@
 from lib.model.model import Model
 from lib.schemas import Message, ClassyCatBatchClassificationResponse
 from lib.s3 import load_file_from_s3, file_exists_in_s3, upload_file_to_s3
+from lib.base_exception import PrestoBaseException
 
 
 class LLMClient:
@@ -65,7 +66,9 @@ def classify(self, task_prompt, items_count, max_tokens_per_item=200):
             max_tokens=(max_tokens_per_item * items_count) + 15,
             temperature=0.5
         )
-# TODO: record metric here with model name and number of items submitted (https://meedan.atlassian.net/browse/CV2-4987)
+
+        # TODO: record metric here with model name and number of items submitted (https://meedan.atlassian.net/browse/CV2-4987)
+
         return completion.choices[0].message.content
 
 
@@ -84,7 +87,7 @@ def get_llm_client(self, client_type, model_name):
         elif client_type == 'openrouter':
             return OpenRouterClient(model_name)
         else:
-            raise Exception(f"Unknown client type: {client_type}")
+            raise PrestoBaseException(f"Unknown LLM client type {client_type}", 500)
 
     def format_input_for_classification_prompt(self, items):
         return '\n'.join([f"<ITEM_{i}>{item}</ITEM_{i}>" for i, item in enumerate(items)])
@@ -119,8 +122,7 @@ def classify_and_store_results(self, schema_id, items):
         if (classification_results is None or len(classification_results) == 0
                 or len(classification_results) != len(items)):
             logger.info(f"Classification results: {classification_results}")
-            raise Exception(f"Not all items were classified successfully: "
-                            f"input length {len(items)}, output length {len(classification_results)}")
+            raise PrestoBaseException(f"Not all items were classified successfully: input length {len(items)}, output length {len(classification_results)}", 502)
 
         final_results = [{'id': items[i]['id'], 'text': items[i]['text'], 'labels': classification_results[i]}
                          for i in range(len(items))]
@@ -213,18 +215,18 @@ def process(self, message: Message) -> ClassyCatBatchClassificationResponse:
         result = message.body.result
 
         if not self.schema_id_exists(schema_id):
-            result.responseMessage = f"Schema id {schema_id} cannot be found"
-            return result
+            raise PrestoBaseException(f"Schema id {schema_id} cannot be found", 404)
 
         if len(items) > self.batch_size_limit:
-            result.responseMessage = f"Number of items exceeds batch size limit of {self.batch_size_limit}"
-            return result
+            raise PrestoBaseException(f"Number of items exceeds batch size limit of {self.batch_size_limit}", 422)
 
         try:
             result.classification_results = self.classify_and_store_results(schema_id, items)
             result.responseMessage = "success"
             return result
         except Exception as e:
             logger.exception(f"Error classifying items: {e}")
-            result.responseMessage = f"Error classifying items: {e}"
-            return result
+            if isinstance(e, PrestoBaseException):
+                raise e
+            else:
+                raise PrestoBaseException(f"Error classifying items: {e}", 500) from e

lib/model/classycat_schema_create.py

@@ -5,6 +5,7 @@
 from lib.logger import logger
 from lib.model.model import Model
 from lib.schemas import Message, ClassyCatSchemaResponse
+from lib.base_exception import PrestoBaseException
 
 
 class Model(Model):
@@ -192,24 +193,21 @@ def process(self, message: Message) -> ClassyCatSchemaResponse:
         result = message.body.result
 
         if self.schema_name_exists(schema_name):
-            result.responseMessage = f"Schema name {schema_name} already exists"
-            return result
+            raise PrestoBaseException(f"Schema name {schema_name} already exists", 422)
 
         try:
             self.verify_schema_parameters(schema_name, topics, examples, languages)
         except Exception as e:
             logger.exception(f"Error verifying schema parameters: {e}")
-            result.responseMessage = f"Error verifying schema parameters. Stack trace: {e}"
-            return result
+            raise PrestoBaseException(f"Error verifying schema parameters: {e}", 422) from e
 
         try:
             result.schema_id = self.create_schema(schema_name, topics, examples, languages)
             result.responseMessage = 'success'
             return result
         except Exception as e:
             logger.exception(f"Error creating schema: {e}")
-            result.responseMessage = f"Error creating schema. Stack trace: {e}"
-            return result
+            raise PrestoBaseException(f"Error creating schema: {e}", 500) from e
 
 
     def verify_schema_parameters(self, schema_name, topics, examples, languages): #todo

lib/model/classycat_schema_lookup.py

@@ -4,6 +4,7 @@
 from lib.model.model import Model
 from lib.s3 import load_file_from_s3, file_exists_in_s3
 from lib.schemas import Message, ClassyCatSchemaResponse
+from lib.base_exception import PrestoBaseException
 
 
 class Model(Model):
@@ -63,8 +64,7 @@ def process(self, message: Message) -> ClassyCatSchemaResponse:
         result = message.body.result
 
         if not self.schema_name_exists(schema_name):
-            result.responseMessage = f"Schema name {schema_name} does not exist"
-            return result
+            raise PrestoBaseException(f"Schema name {schema_name} does not exist", 404)
 
         logger.debug(f"located schema_name record for '{schema_name}'")
 
@@ -74,5 +74,4 @@ def process(self, message: Message) -> ClassyCatSchemaResponse:
             return result
         except Exception as e:
             logger.error(f"Error looking up schema name {schema_name}: {e}")
-            result.responseMessage = f"Error looking up schema name {schema_name}: {e}"
-            return result
+            raise PrestoBaseException(f"Error looking up schema name {schema_name}", 500) from e

lib/model/model.py

@@ -10,9 +10,12 @@
 from lib import schemas
 from lib.cache import Cache
 from lib.sentry import capture_custom_message
+from lib.base_exception import PrestoBaseException
+
 
 class Model(ABC):
     BATCH_SIZE = 1
+
     def __init__(self):
         self.model_name = os.environ.get("MODEL_NAME")
 
@@ -43,18 +46,18 @@ def get_tempfile(self) -> Any:
     def process(self, messages: Union[List[schemas.Message], schemas.Message]) -> List[schemas.Message]:
         return []
 
-    def handle_fingerprinting_error(self, e):
+    def handle_fingerprinting_error(self, e: Exception, response_code: int = 500) -> schemas.ErrorResponse:
         error_context = {"error": str(e)}
         for attr in ["__cause__", "__context__", "args", "__traceback__"]:
             if attr in dir(e):
                 if attr == "__traceback__":
                     error_context[attr] = '\n'.join(traceback.format_tb(getattr(e, attr)))
                 else:
                     error_context[attr] = str(getattr(e, attr))
-        capture_custom_message("Error during fingerprinting for {self.model_name}", 'info', error_context)
-        return schemas.ErrorResponse(error=str(e), error_details=error_context)
+        capture_custom_message(f"Error during fingerprinting for {self.model_name}", 'error', error_context)
+        return schemas.ErrorResponse(error=str(e), error_details=error_context, error_code=response_code)
 
-    def get_response(self, message: schemas.Message) -> schemas.GenericItem:
+    def get_response(self, message: schemas.Message) -> schemas.GenericItem:  # TODO note: the return type is wrong here
         """
         Perform a lookup on the cache for a message, and if found, return that cached value.
         """
@@ -64,7 +67,10 @@ def get_response(self, message: schemas.Message) -> schemas.GenericItem:
                 result = self.process(message)
                 Cache.set_cached_result(message.body.content_hash, result)
             except Exception as e:
-                return self.handle_fingerprinting_error(e)
+                if isinstance(e, PrestoBaseException):
+                    return self.handle_fingerprinting_error(e, e.error_code)
+                else:
+                    return self.handle_fingerprinting_error(e)
         return result
 
     def respond(self, messages: Union[List[schemas.Message], schemas.Message]) -> List[schemas.Message]:
@@ -76,7 +82,7 @@ def respond(self, messages: Union[List[schemas.Message], schemas.Message]) -> Li
         for message in messages:
             message.body.result = self.get_response(message)
         return messages
-    
+
     @classmethod
     def create(cls):
         """

test/lib/model/test_classycat.py

@@ -3,6 +3,7 @@
 from unittest.mock import MagicMock, patch
 from lib.model.classycat import Model as ClassyCatModel
 from lib import schemas
+from lib.base_exception import PrestoBaseException
 import json
 
 
@@ -562,9 +563,11 @@ def test_classify_fail_wrong_response_format(self, file_exists_in_s3_mock, uploa
             }
         }
         classify_message = schemas.parse_message(classify_input)
-        result = self.classycat_model.process(classify_message)
 
-        self.assertEqual(result.responseMessage, "Error classifying items: list index out of range")
+        with self.assertRaises(PrestoBaseException) as e:
+            self.classycat_model.process(classify_message)
+            self.assertIn("Error classifying items: list index out of range", e.message)
+            self.assertEqual(e.error_code, 500)
 
     @patch('lib.model.classycat_classify.OpenRouterClient.classify')
     @patch('lib.model.classycat_classify.load_file_from_s3')
@@ -700,15 +703,18 @@ def test_classify_fail_wrong_number_of_results(self, file_exists_in_s3_mock, upl
             }
         }
         classify_message = schemas.parse_message(classify_input)
-        result = self.classycat_model.process(classify_message)
 
-        self.assertEqual(result.responseMessage, "Error classifying items: Not all items were classified successfully: input length 1, output length 2")
+        with self.assertRaises(PrestoBaseException) as e:
+            self.classycat_model.process(classify_message)
+            self.assertIn("Not all items were classified successfully: input length 1, output length 2", e.message)
+            self.assertEqual(e.error_code, 502)
+
 
     @patch('lib.model.classycat_classify.OpenRouterClient.classify')
     @patch('lib.model.classycat_classify.load_file_from_s3')
     @patch('lib.model.classycat_classify.upload_file_to_s3')
     @patch('lib.model.classycat_classify.file_exists_in_s3')
-    def test_classify_pass_some_out_of_schema_labels(self, file_exists_in_s3_mock, upload_file_to_s3_mock,
+    def test_classify_some_out_of_schema_labels(self, file_exists_in_s3_mock, upload_file_to_s3_mock,
                                                      load_file_from_s3_mock, openrouter_classify_mock):
         file_exists_in_s3_mock.return_value = True
         upload_file_to_s3_mock.return_value = None
@@ -858,7 +864,7 @@ def test_classify_pass_some_out_of_schema_labels(self, file_exists_in_s3_mock, u
     @patch('lib.model.classycat_classify.load_file_from_s3')
     @patch('lib.model.classycat_classify.upload_file_to_s3')
     @patch('lib.model.classycat_classify.file_exists_in_s3')
-    def test_classify_fail_all_out_of_schema_labels(self, file_exists_in_s3_mock, upload_file_to_s3_mock,
+    def test_classify_all_out_of_schema_labels(self, file_exists_in_s3_mock, upload_file_to_s3_mock,
                                                     load_file_from_s3_mock, openrouter_classify_mock):
         file_exists_in_s3_mock.return_value = True
         upload_file_to_s3_mock.return_value = None