Table of Contents

• Console

  • Class: Console

    • new Console(stdout[, stderr][, ignoreErrors])
    • new Console(options)
    • console.assert(value[, ...message])
    • console.clear()
    • console.count([label])
    • console.countReset([label])
    • console.debug(data[, ...args])
    • console.dir(obj[, options])
    • console.dirxml(...data)
    • console.error([data][, ...args])
    • console.group([...label])
    • console.groupCollapsed()
    • console.groupEnd()
    • console.info([data][, ...args])
    • console.log([data][, ...args])
    • console.table(tabularData[, properties])
    • console.time([label])
    • console.timeEnd([label])
    • console.timeLog([label][, ...data])
    • console.trace([message][, ...args])
    • console.warn([data][, ...args])

  • Inspector only methods

    • console.profile([label])
    • console.profileEnd([label])
    • console.timeStamp([label])

Console#

The console module provides a simple debugging console that is similar to the JavaScript console mechanism provided by web browsers.

The module exports two specific components:

• A Console class with methods such as console.log(), console.error() and console.warn() that can be used to write to any Node.js stream.
• A global console instance configured to write to process.stdout and process.stderr. The global console can be used without calling require('console').

Warning: The global console object's methods are neither consistently synchronous like the browser APIs they resemble, nor are they consistently asynchronous like all other Node.js streams. See the note on process I/O for more information.

Example using the global console:

console.log('hello world');
// Prints: hello world, to stdout
console.log('hello %s', 'world');
// Prints: hello world, to stdout
console.error(new Error('Whoops, something bad happened'));
// Prints: [Error: Whoops, something bad happened], to stderr

const name = 'Will Robinson';
console.warn(`Danger ${name}! Danger!`);
// Prints: Danger Will Robinson! Danger!, to stderr

Example using the Console class:

const out = getStreamSomehow();
const err = getStreamSomehow();
const myConsole = new console.Console(out, err);

myConsole.log('hello world');
// Prints: hello world, to out
myConsole.log('hello %s', 'world');
// Prints: hello world, to out
myConsole.error(new Error('Whoops, something bad happened'));
// Prints: [Error: Whoops, something bad happened], to err

const name = 'Will Robinson';
myConsole.warn(`Danger ${name}! Danger!`);
// Prints: Danger Will Robinson! Danger!, to err

Class: Console#

The Console class can be used to create a simple logger with configurable output streams and can be accessed using either require('console').Console or console.Console (or their destructured counterparts):

const { Console } = require('console');

const { Console } = console;

new Console(stdout[, stderr][, ignoreErrors])#

new Console(options)#

• options