@yambwa/pretty-logger/dist/logger.js

A lightweight, extensible logger with log levels, pretty and JSON output, context support, and pluggable transports for Node.js and TypeScript projects.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.createLogger = createLogger;
const types_1 = require("./types");
const formatters_1 = require("./formatters");
/**
 * Logger implementation
 */
class Logger {
    constructor(config = {}) {
        this.level = config.level || types_1.LogLevel.Info;
        this.context = config.context;
        // Determine mode based on NODE_ENV if not explicitly set
        if (config.mode) {
            this.mode = config.mode;
        }
        else {
            this.mode = process.env.NODE_ENV === 'production' ? 'json' : 'pretty';
        }
        // Use provided transports or default to console
        this.transports = config.transports || [formatters_1.defaultConsoleTransport];
    }
    log(level, message, meta) {
        // Check if this level should be logged
        if (types_1.logLevelRanks[level] < types_1.logLevelRanks[this.level]) {
            return;
        }
        const entry = {
            level,
            message,
            timestamp: new Date(),
            context: this.context,
            meta,
        };
        const formatter = this.mode === 'json' ? formatters_1.formatJSON : formatters_1.formatPretty;
        const formatted = formatter(entry);
        // Send to all transports
        for (const transport of this.transports) {
            try {
                transport(entry, formatted);
            }
            catch (error) {
                // Prevent transport errors from breaking logging
                console.error('Transport error:', error);
            }
        }
    }
    trace(message, meta) {
        this.log(types_1.LogLevel.Trace, message, meta);
    }
    debug(message, meta) {
        this.log(types_1.LogLevel.Debug, message, meta);
    }
    info(message, meta) {
        this.log(types_1.LogLevel.Info, message, meta);
    }
    warn(message, meta) {
        this.log(types_1.LogLevel.Warn, message, meta);
    }
    error(message, meta) {
        this.log(types_1.LogLevel.Error, message, meta);
    }
    fatal(message, meta) {
        this.log(types_1.LogLevel.Fatal, message, meta);
    }
    setLevel(level) {
        this.level = level;
    }
    withContext(context) {
        return new Logger({
            level: this.level,
            mode: this.mode,
            context,
            transports: this.transports,
        });
    }
}
/**
 * Create a new logger instance
 */
function createLogger(config) {
    return new Logger(config);
}