remix-project/libs/remix-tests/src/logger.ts

import colors from 'colors'
import winston, { Logger, LoggerOptions } from 'winston'
import timestamp from 'time-stamp';
import supportsColor from 'color-support'

function hasFlag (flag: string) {
    return ((typeof (process) !== 'undefined') && (process.argv.indexOf('--' + flag) !== -1))
}

function addColor (str: string) {
    if (hasFlag('no-color')) {
        return str
    }

    if (hasFlag('color')) {
        return colors.gray(str)
    }

    if (supportsColor()) {
        return colors.gray(str)
    }

    return str
}
function getTimestamp () {
    return '[' + addColor(timestamp('HH:mm:ss')) + ']'
}
// create winston logger format
const logFmt = winston.format.printf((info) => {
    return `${getTimestamp()} ${info.level}: ${info.message}`
})

class Log {
    logger: Logger;
    constructor () {
        this.logger = winston.createLogger({
            level: 'info',
            transports: [new winston.transports.Console()],
            format: winston.format.combine(
                winston.format.colorize({ all: true }),
                logFmt
            )
        })
    }
    setVerbosity (v: LoggerOptions["level"]): void {
        this.logger.configure({
            level: v,
            transports: [new winston.transports.Console()],
            format: winston.format.combine(
                winston.format.colorize({ all: true }),
                logFmt
            )
        })
    }
}

export = Log