Addresses Issue langchain-ai#245

Added `logger_util` to enable package and class wide logging in `langchain-aws`.
Added logging for `invoke` and `ainvoke`.

libs/aws/langchain_aws/chat_models/bedrock.py

@@ -37,7 +37,7 @@
 from langchain_core.tools import BaseTool
 from langchain_core.utils.pydantic import TypeBaseModel, is_basemodel_subclass
 from pydantic import BaseModel, ConfigDict, model_validator
-
+import logging
 from langchain_aws.chat_models.bedrock_converse import ChatBedrockConverse
 from langchain_aws.function_calling import (
     ToolsOutputParser,
@@ -53,7 +53,9 @@
     get_num_tokens_anthropic,
     get_token_ids_anthropic,
 )
+from langchain_aws.logger_util import get_logger
 
+logger = get_logger(__name__)
 
 def _convert_one_message_to_text_llama(message: BaseMessage) -> str:
     if isinstance(message, ChatMessage):
@@ -520,6 +522,7 @@ def _generate(
         run_manager: Optional[CallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> ChatResult:
+        logger.info(f"The input message sent by user: {messages}")
         if self.beta_use_converse_api:
             return self._as_converse._generate(
                 messages, stop=stop, run_manager=run_manager, **kwargs
@@ -595,7 +598,7 @@ def _generate(
             tool_calls=cast(List[ToolCall], tool_calls),
             usage_metadata=usage_metadata,
         )
-
+        logger.info(f"The output message sent by user: {msg}")
         return ChatResult(
             generations=[
                 ChatGeneration(

libs/aws/langchain_aws/chat_models/bedrock_converse.py

@@ -19,6 +19,7 @@
     cast,
 )
 
+import logging
 import boto3
 from langchain_core.callbacks import CallbackManagerForLLMRun
 from langchain_core.language_models import BaseChatModel, LanguageModelInput
@@ -52,10 +53,11 @@
 from typing_extensions import Self
 
 from langchain_aws.function_calling import ToolsOutputParser
-
+from langchain_aws.logger_util import get_logger
 _BM = TypeVar("_BM", bound=BaseModel)
 _DictOrPydanticClass = Union[Dict[str, Any], Type[_BM], Type]
 
+logger = get_logger(__name__)
 
 class ChatBedrockConverse(BaseChatModel):
     """Bedrock chat model integration built on the Bedrock converse API.
@@ -495,13 +497,15 @@ def _generate(
     ) -> ChatResult:
         """Top Level call"""
         bedrock_messages, system = _messages_to_bedrock(messages)
+        logger.debug(f"input message: {bedrock_messages}")
         params = self._converse_params(
             stop=stop, **_snake_to_camel_keys(kwargs, excluded_keys={"inputSchema"})
         )
         response = self.client.converse(
             messages=bedrock_messages, system=system, **params
         )
         response_message = _parse_response(response)
+        logger.info(f"output message: {response_message}")
         return ChatResult(generations=[ChatGeneration(message=response_message)])
 
     def _stream(

libs/aws/langchain_aws/logger_util.py

@@ -0,0 +1,70 @@
+import logging
+import os
+import sys
+
+__DEBUG = True if os.environ.get('LANGCHAIN_AWS_DEBUG') else False
+__ROOT_DEBUG = __DEBUG if os.environ.get('LANGCHAIN_AWS_DEBUG_ROOT') else False
+
+if __DEBUG:
+    DEFAULT_LOG_LEVEL: int = logging.DEBUG
+else:
+    DEFAULT_LOG_LEVEL: int = logging.ERROR
+
+DEFAULT_LOG_FILE = os.environ.get('LANGCHAIN_AWS_LOG_OUTPUT', '-')
+if DEFAULT_LOG_FILE == '-':
+    DEFAULT_LOG_HANDLER: logging.Handler = None
+else:
+    DEFAULT_LOG_HANDLER: logging.Handler = logging.FileHandler(DEFAULT_LOG_FILE)
+
+if __DEBUG:
+    DEFAULT_LOG_FORMAT: str = '%(asctime)s %(levelname)s | [%(filename)s:%(lineno)s] | - %(name)s - %(message)s'
+else:
+    DEFAULT_LOG_FORMAT: str = '%(asctime)s %(levelname)s | %(name)s - %(message)s'
+
+try:
+    import colorama
+    import coloredlogs
+
+    colorama.init()
+
+    if DEFAULT_LOG_HANDLER:
+        DEFAULT_LOG_FORMATTER: logging.Formatter = logging.Formatter(DEFAULT_LOG_FORMAT)
+    else:
+        DEFAULT_LOG_FORMATTER: logging.Formatter = coloredlogs.ColoredFormatter(DEFAULT_LOG_FORMAT)
+
+except ImportError:
+    colorama = None
+    coloredlogs = None
+
+    DEFAULT_LOG_FORMATTER: logging.Formatter = logging.Formatter(DEFAULT_LOG_FORMAT)
+
+def get_logger(logger_name: str=None, log_handler: logging.Handler = DEFAULT_LOG_HANDLER,
+log_formatter: logging.Formatter = DEFAULT_LOG_FORMATTER,
+log_level: int = DEFAULT_LOG_LEVEL) -> logging.Logger:
+    '''
+    Define a logger with the passed module_name at module level or function level
+    '''
+    logger = logging.getLogger(logger_name)
+
+    # Do not customize root logger.
+    if logger_name or __ROOT_DEBUG:
+        if not log_handler:
+            log_handler = logging.StreamHandler()
+
+            # add formatter to handler
+            log_handler.setFormatter(log_formatter)
+
+        if log_handler:
+            try:
+                logger.removeHandler(log_handler)
+            except:
+                pass
+            logger.addHandler(log_handler)
+
+        if logger_name:
+            logger.propagate = False
+
+    logger.setLevel(log_level)
+    return logger
+
+ROOT_LOGGER = get_logger()