apify__agent-skills/plugins/apify-dev-tools/skills/apify-actor-development/references/logging.md

Actor Logging Reference

JavaScript and TypeScript

ALWAYS use the apify/log package for logging - This package contains critical security logic including censoring sensitive data (Apify tokens, API keys, credentials) to prevent accidental exposure in logs.

Available Log Levels in apify/log

The Apify log package provides the following methods for logging:

• log.debug() - Debug level logs (detailed diagnostic information)
• log.info() - Info level logs (general informational messages)
• log.warning() - Warning level logs (warning messages for potentially problematic situations)
• log.warningOnce() - Warning level logs (same warning message logged only once)
• log.error() - Error level logs (error messages for failures)
• log.exception() - Exception level logs (for exceptions with stack traces)
• log.perf() - Performance level logs (performance metrics and timing information)
• log.deprecated() - Deprecation level logs (warnings about deprecated code)
• log.softFail() - Soft failure logs (non-critical failures that don't stop execution, e.g., input validation errors, skipped items)
• log.internal() - Internal level logs (internal/system messages)

Best Practices

• Use log.debug() for detailed operation-level diagnostics (inside functions)
• Use log.info() for general informational messages (API requests, successful operations)
• Use log.warning() for potentially problematic situations (validation failures, unexpected states)
• Use log.error() for actual errors and failures
• Use log.exception() for caught exceptions with stack traces

Python

ALWAYS use Actor.log for logging - This logger contains critical security logic including censoring sensitive data (Apify tokens, API keys, credentials) to prevent accidental exposure in logs.

Available Log Levels

The Apify Actor logger provides the following methods for logging:

• Actor.log.debug() - Debug level logs (detailed diagnostic information)
• Actor.log.info() - Info level logs (general informational messages)
• Actor.log.warning() - Warning level logs (warning messages for potentially problematic situations)
• Actor.log.error() - Error level logs (error messages for failures)
• Actor.log.exception() - Exception level logs (for exceptions with stack traces)

Best Practices

• Use Actor.log.debug() for detailed operation-level diagnostics (inside functions)
• Use Actor.log.info() for general informational messages (API requests, successful operations)
• Use Actor.log.warning() for potentially problematic situations (validation failures, unexpected states)
• Use Actor.log.error() for actual errors and failures
• Use Actor.log.exception() for caught exceptions with stack traces