Empty Gateway Env Fix

What it does

This bug fix patches a crash that occurred when a LangChain gateway environment variable was set to an empty string instead of being fully absent or set to a non-empty value. Previously an empty gateway env var like LANGCHAIN_API_KEY="" made the gateway raise an exception or behave unexpectedly. The fix makes the gateway gracefully treat empty-string env vars as equivalent to unset variables rather than crashing.

Why it matters

Production deployments often set environment variables through Kubernetes Secrets, Docker Compose, or CI/CD pipelines where a variable might be explicitly set to an empty string as a placeholder. If your app reads gateway config from env vars, an inadvertent MY_VAR="" could silently break the whole application. This fix prevents that entire class of failure, especially for containerized or auto-scaled services where empty-string env vars are common.

Example

$ import os
os.environ["LANGCHAIN_API_KEY"] = ""  # intentionally empty
config = Gateway.get_config_from_env()
print("Config loaded:", config)
print("api_key value:", repr(config.get("api_key")))

Config loaded: {'api_key': None, 'other_setting': 'default_value'}
api_key value: None

Common flags

Gateway.get_config_from_env()

Reads gateway configuration from environment variables

LANGCHAIN_API_KEY=""

Empty-string case now coerced to unset/None

handle_empty_string_in_gateway_env_vars

The internal guard behind the fix