How to output the contents logged by langsmith to a local log file as well

[arrowkato]

I'm using langsmith, but it's a hassle to check the web page every time.
Please tell me how to output the log to a local file (e.g. langsmith.log).

Thank you

[dosubot[bot]]

Hey @arrowkato! I'm here to assist you with any bugs, questions, or contributions you have. Let's tackle this together! 😊

LangSmith uses the Python logging library for logging ^[1]. To output logs to a local file, you can configure a file handler in your logging setup. Here's a basic example of how you can do this:

import logging

# Create a logger
logger = logging.getLogger('langsmith')
logger.setLevel(logging.DEBUG)  # Set the logging level

# Create a file handler
file_handler = logging.FileHandler('langsmith.log')
file_handler.setLevel(logging.DEBUG)

# Create a logging format
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
file_handler.setFormatter(formatter)

# Add the file handler to the logger
logger.addHandler(file_handler)

# Example log message
logger.info('This is a log message.')

This script sets up a logger that writes log messages to a file named langsmith.log. You can adjust the logging level and format as needed. Make sure to integrate this setup into your application where LangSmith logging is initialized.

To continue talking to Dosu, mention @dosu.

[arrowkato]

@dosu

I didn't get the results I was expecting.

Please tell me the source code where the logger definition used by default in langchain is defined.

[dosubot[bot]]

The specific source code where the logger for LangSmith is defined or initialized in LangChain is not explicitly documented in the available information. However, logging for LangSmith is handled in the module libs/langchain/langchain/callbacks/tracers/log_stream.py, which includes components like LogEntry, LogStreamCallbackHandler, RunLog, RunLogPatch, and RunState ^[1]. You might want to explore this module to understand how logging is set up and potentially customize it to suit your needs.

To continue talking to Dosu, mention @dosu.