src/logger.js

import { pino } from "pino";
import pretty from "pino-pretty";
import path from "path";

let fileLogger;
let logFileDestination;

/**
 * Initialize the standard out and file loggers.
 * @param directory the directory in which to create the log file
 * @param quiet true if the standard output should be minimalized to errors only
 * @param logLevel the file log level
 */
function loggerInit(directory, quiet = false, logLevel = 'info') {
    // replaces characters that windows does not allow in filenames
    logFileDestination = path.join(directory, 'log_' + new Date().toISOString().replaceAll(/[.:]/g, '-') + '.txt');
    const streams = [
        {
            level: logLevel,
            stream: pretty({
                destination: logFileDestination,
                mkdir: true,
                colorize: false,
                translateTime: 'yyyy-mm-dd HH:MM:ss',
                ignore: 'pid,hostname'
            })
        },
    ]

    // using pino.multistream seems to resolve some issues with file logging in windows environments that occurred when pino.transport was used instead
    fileLogger = pino({
        level: logLevel
    }, pino.multistream(streams));
    if (quiet) {
        console.log = function(){};
        console.info = function(){};
        console.debug = function(){};
    }
}

function log(level, text, options = {toConsole: false}) {
    let detail = options.detail;
    if (detail) {
        if (options.toConsole) {
            console.log(text + ': ' + yellow(detail));
        }
        fileLogger[level](removeYellow(text) + ': ' + removeYellow(detail));
    } else {
        if (options.toConsole) {
            console.log(text);
        }
        // remove any yellow which may have been added by the caller
        fileLogger[level](removeYellow(text));
    }
}

function loggerInfo(text, options = {toConsole: false}) {
    log('info', text, options);
}

function loggerDebug(text, options = {toConsole: false}) {
    log('debug', text, options);
}

/**
 * Log an error to console and file. A simplified error message will be output to console while a more detailed error will be logged to file.
 * @param errorMessage the error message to log to console and file
 * @param error optional error object that caused the error
 */
function loggerError(errorMessage, error) {
    let toConsole = errorMessage;
    let toLog = removeYellow(errorMessage);
    if (error) {
        toConsole = toConsole + ': ' + error.message + ' - Please see ' + logFileDestination + ' for more details';
        toLog = toLog + '\n' + JSON.stringify(error, null, 4);
    }
    console.error(toConsole);
    fileLogger.error(toLog);
}

function yellow(text) {
    return '\x1b[33m' + text + '\x1b[0m';
}

function removeYellow(text) {
    let withoutYellow = text.replaceAll(/\x1b\[33m/g, '');
    return withoutYellow.replaceAll(/\x1b\[0m/g, '');
}

export { loggerInit, loggerInfo, loggerError, loggerDebug, yellow };