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Basic Console Logging

This example demonstrates the simplest way to get started with Logly for console logging with beautiful colored output.

Simple Example (NEW in v0.1.5)

No configuration needed - just import and log with automatic colors:

from logly import logger

# Start logging immediately with colored output
logger.trace("Entering main function")           # Cyan (most verbose)
logger.debug("Debug information")                # Blue
logger.info("Application started")               # White
logger.success("Database connected")             # Green
logger.warning("Cache is full")                  # Yellow
logger.error("Connection timeout")               # Red
logger.critical("System out of memory")          # Bright Red
logger.fail("Authentication failed", user="bob") # Magenta (NEW)

# Log with extra data
logger.info("User logged in", user_id=12345)
logger.success("Payment processed", amount=99.99, card_last4="1234")
logger.fail("Login failed", attempts=3, reason="invalid_password")

Advanced Example (Customize Settings)

If you need custom settings:

from logly import logger

# Customize console output (optional)
logger.configure(level="DEBUG", color=True)

# Log some messages
logger.debug("Debug messages now visible")
logger.info("Application started")
logger.warning("This is a warning message")
logger.error("This is an error message")

logger.complete()

Expected Output

2025-01-15T14:30:00.123456+00:00 [TRACE] Entering main function
2025-01-15T14:30:00.124567+00:00 [DEBUG] Debug information
2025-01-15T14:30:00.125678+00:00 [INFO] Application started
2025-01-15T14:30:00.126789+00:00 [SUCCESS] Database connected
2025-01-15T14:30:00.127890+00:00 [WARN] Cache is full
2025-01-15T14:30:00.128901+00:00 [ERROR] Connection timeout
2025-01-15T14:30:00.129012+00:00 [CRITICAL] System out of memory
2025-01-15T14:30:00.130123+00:00 [FAIL] Authentication failed | user=bob
2025-01-15T14:30:00.131234+00:00 [INFO] User logged in | user_id=12345
2025-01-15T14:30:00.132345+00:00 [SUCCESS] Payment processed | amount=99.99 | card_last4=1234
2025-01-15T14:30:00.133456+00:00 [FAIL] Login failed | attempts=3 | reason=invalid_password

Colors in Terminal: - TRACE appears in cyan - DEBUG appears in blue - INFO appears in white - SUCCESS appears in green - WARN appears in yellow - ERROR appears in red - CRITICAL appears in bright red - FAIL appears in magenta (NEW)

What Happens

  1. Auto-configuration on import:
  2. Logger is automatically configured with color=True
  3. Console sink created automatically with auto_sink=True
  4. Default colors applied to all log levels

  5. No configure() call needed for basic usage

  6. Colored output:

  7. Each level gets its default color (customizable)
  8. FAIL level (NEW) displays in magenta

  9. Colors help distinguish severity at a glance

  10. Extra fields are appended:

  11. Fields like user_id=12345 are automatically formatted

  12. Multiple fields are separated by | characters

  13. Timestamps are included:

  14. ISO 8601 format with microsecond precision
  15. Timezone aware (UTC by default)

Key Features Demonstrated

  • Zero configuration: Just import and log - works immediately
  • Automatic colors: Default color mapping for all 8 log levels
  • FAIL level: New level for operation failures (v0.1.5)
  • Level filtering: Only show messages at or above configured level
  • Console control: Enable/disable console output with console parameter