iwmlib/lib/logging.js

/* eslint-disable no-undef */
/* eslint-disable no-console */
/* eslint-disable no-unused-vars */
let ipc = null
let logMessages = new Set()
let logHandlers = {
    log: console.log,
    warn: console.warn,
    error: console.error
}

try {
    ipc = require('electron').ipcRenderer
    logHandlers.log = message => ipc.send('log', message)
    logHandlers.warn = message => ipc.send('warn', message)
    logHandlers.error = message => ipc.send('error', message)
} catch (e) {
    console.log('Cannot use electron logging.')
}

/** Basic class for app specific logging requirements.
 * Can be used to implement persistent logging in electron apps.
 * Uses a logMessage cache to prevent error overflows. This is 
 * needed since errors may occur very frequently
 * (e.g. display update loops at 60fps, programmatic loops, ...).
 * 
 * The logging handlers can be overwritten by calling the static
 * setup method.
 */
export default class Logging {

    /** Static log function.
     * @param {*} message
     */
    static log(message) {
        logHandlers.log(message)
    }

    /**
     * Static warn function. 
     * Emits each warning only once per session.
     * @param {*} message 
     */
    static warn(message) {
        if (!logMessages.has(message)) {
            logMessages.add(message)
            logHandlers.warn(message)
        }
    }

    /**
    * Static error function. 
    * Emits each error message only once per session.
    * @param {*} message 
    */
    static error(message) {
        if (!logMessages.has(message)) {
            logMessages.add(message)
            logHandlers.error(message)
        }
    }

    static setup({log=console.log, warn=console.warn, error=console.error} = {}) {
        logHandlers.log = log
        logHandlers.warn = warn
        logHandlers.error = error
    }
}