Toolbox: Logger

The logger provides methods for outputting messages at different log levels.

Basic Usage

cli.addCommand({
    name: "example",
    execute: ({ logger }) => {
        logger.info("Information message");
        logger.error("Error message");
        logger.warn("Warning message");
        logger.debug("Debug message");
    },
});

Log Levels

Info

General information messages:

logger.info("Building project...");
logger.info("Files processed:", fileCount);

Error

Error messages:

logger.error("Failed to build");
logger.error("Error details:", error);

Warn

Warning messages:

logger.warn("Deprecated option used");
logger.warn("This feature will be removed in v2.0");

Debug

Debug messages (only shown with --debug flag):

logger.debug("Processing file:", fileName);
logger.debug("Options:", options);

Logging Objects

Logger methods accept multiple arguments:

logger.info("User:", user.name, "Age:", user.age);
logger.error("Error:", error.message, error.stack);

Verbosity Control

Log levels are controlled by verbosity flags:

cli command              # Shows info, warn, error
cli command --verbose    # Shows debug too
cli command --debug      # Shows all debug messages
cli command --quiet      # Minimal output

Custom Logger

Provide a custom logger when creating the CLI:

const customLogger = {
    info: (...args) => console.log("[INFO]", ...args),
    error: (...args) => console.error("[ERROR]", ...args),
    warn: (...args) => console.warn("[WARN]", ...args),
    debug: (...args) => {
        if (process.env.DEBUG) {
            console.debug("[DEBUG]", ...args);
        }
    },
};

const cli = new Cerebro("my-app", {
    logger: customLogger,
});

Conditional Logging

Use log levels appropriately:

execute: ({ logger, options }) => {
    if (options.verbose) {
        logger.debug("Detailed processing information");
    }

    logger.info("Starting operation...");

    try {
        // Operation
    } catch (error) {
        logger.error("Operation failed:", error);
    }
};

Best Practices

Use appropriate levels - info for normal output, error for errors
Don't overuse debug - Reserve for troubleshooting
Include context - Log relevant information
Format consistently - Use consistent message formats
Respect verbosity - Don't force output in quiet mode

Logger