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React Console Log Captures console.log's into a React Component

A React component that displays console logs from the current page, an iframe or transported across a server.


Who's using it


  • Console formatting - style and give your logs color, and makes links clickable
  • DOM nodes - easily inspect & expand HTML elements, with syntax highlighting
  • console.table - view your logs in a table format
  • Other console methods:
    • console.time - view the time in milliseconds it takes to complete events
    • console.assert - assert that a statement is truthy
    • console.count - count how many times something occurs
  • Inbuilt JSON serialization - Objects, Functions & DOM elements can be encoded / decoded to and from JSON


yarn add console-feed
# or
npm install console-feed
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Basic usage


import React from 'react'
import { Hook, Console, Decode } from 'console-feed'

class App extends React.Component {
  state = {
    logs: []

  componentDidMount() {
    Hook(window.console, log => {
      this.setState(({ logs }) => ({ logs: [...logs, Decode(log)] }))

    console.log(`Hello world!`)

  render() {
    return (
      <div style={{ backgroundColor: '#242424' }}>
        <Console logs={this.state.logs} variant="dark" />
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Props for <Console /> component

logs: Log[]

An array consisting of Log objects. Required

filter?: Methods[]

Filter the logs, only displaying messages of certain methods.

variant?: 'light' | 'dark'

Sets the font color for the component. Default - light

style?: Styles

Defines the custom styles to use on the component - see Styles.d.ts

searchKeywords?: string

A string value to filter logs

logFilter?: Function

If you want to use a custom log filter function, you can provide your own implementation

Log methods

Each log has a method assigned to it. The method is used to determine the style of the message and for the filter prop.

type Methods =
  | 'log'
  | 'warn'
  | 'error'
  | 'info'
  | 'debug'
  | 'command'
  | 'result'
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Log object

A log object consists of the following:

type Logs = Log[]

interface Log {
  // The log method
  method: Methods
  // The arguments passed to console API
  data: any[]
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By default when you use the Hook() API, logs are serialized so that they will safely work with JSON.stringify. In order to restore a log back to format compatible with the <Console /> component, you need to call the Decode() method.

Disabling serialization

If the Hook function and the <Console /> component are on the same origin, you can disable serialization to increase performance.

  log => {
    this.setState(({ logs }) => ({ logs: [...logs, log] }))
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To run console-feed locally, simply run:

yarn start
yarn test:watch
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Head over to http://localhost:3000 in your browser, and you'll see the demo page come up. After you make changes you'll need to reload, but the jest tests will automatically restart.

Discussion (1)

axionbuster profile image
YuJin Kim

Thank you! Using it for a private demo!