Environment variable patterns

Use consistent patterns for environment variable handling in shell scripts. Always provide sensible defaults using the ${VAR:-default} syntax, validate required variables early with clear error messages, and preserve the ability to override configuration values.

For variables with defaults:

strategies=${STRATEGIES:=fast,hi_res,ocr_only}
RUN_SCRIPT=${RUN_SCRIPT:-unstructured-ingest}
PYTHONPATH=${PYTHONPATH:-.}

For required variables, validate early and provide helpful error messages:

if [ -z "$VECTARA_OAUTH_CLIENT_ID" ]; then
  echo "Skipping VECTARA ingest test because VECTARA_OAUTH_CLIENT_ID env var is not set."
  exit 0
fi

Document configurable environment variables in script comments or usage instructions to make them discoverable for users who aren’t familiar with shell scripting. This approach allows scripts to work out-of-the-box with reasonable defaults while remaining flexible for different environments and use cases.