eleko

eleko

a few electron helper functions (mimics puppeteer API) usable inside electron context + node context launch function that spawns an electron child process with an easy to use subset of the same helper functions (mimics puppeteer API)

Easy to use

  const eleko = require( 'eleko' )

  ;( async function () {
    const browser = await eleko.launch()
    const page = await browser.newPage( { show: true } )

    page.on( 'request', function ( req ) {
      const url = req.url
      const resourceType = req.resourceType

      const shouldBlock = (
        resourceType === 'image' ||
        containsAds( url )
      )

      if ( shouldBlock ) {
        console.log( '(x) blocked url: ' + url.slice( 0, 45 ) )
        return req.abort()
      }

      req.continue()
    } )

    await page.goto( 'https://www.youtube.com/watch?v=WY6sR6HQuMw' )
    await page.waitFor( function () {
      const video = document.querySelector( 'video' )

      if ( video ) {
        video.pause()
        if ( !video._play ) {
          // hide play function from YouTube's internal scripts
          // so that it doesn't autoplay
          video._play = video.play
          video.play = function () {}
        }

        if ( video.readyState === 4 ) { // HAVE_ENOUGH_DATA
          video._play()
          return true
        }
      }

      return false // not ready yet
    } )
  } )()

  const adBlockClient = require( 'ad-block-js' ).create()
  require( 'fs' ).readFileSync(
    require( 'path' ).join( __dirname, '../easylist.txt' ), 'utf8'
  )
  .split( /\r?\n/ )
  .forEach( function ( rule ) {
    adBlockClient.add( rule )
  } )

  function containsAds ( url ) {
    return adBlockClient.matches( url )
  }

Electron usage ( helper functions )

CLICK ME

  // this file is run with the electron binary
  const electron = require( 'electron' )
  const eleko = require( 'eleko' )

  // Module to control application life
  const app = electron.app
  // Module to create native browser window
  const BrowserWindow = electron.BrowserWindow

  app.on( 'ready', main )

  let page
  async function main () {
    page = await eleko.newPage()

    // page.win is an instance of BrowserWindow that is updated
    // every time page.goto is called.

    // block ads using a subset of easylist
    eleko.onrequest( page.win, function ( req ) {
        const url = req.url
        const shouldBlock = containsAds( url )
        if ( shouldBlock ) {
          console.log( '(x) blocked url: ' + url.slice( 0, 45 ) )
          return req.abort()
        }
        return req.continue()
    } )

    const url = 'https://www.youtube.com/watch?v=Gu2pVPWGYMQ'
    await page.goto( url )

    // waitFor string
    await eleko.waitFor( page.win, 'video' )

    // evaluate
    await eleko.evaluate( page.win, function () {
      const video = document.querySelector( 'video' )

      video.pause()

      video._play = video.play // keep reference to original
      video.play = function () {} // remove .play so that YouTube's scripts can't play it automatically
    } )

    // get title
    const title = await eleko.evaluate( page.win, function () {
      return document.title
    } )
    console.log( 'title: ' + title )

    // waitFor function
    await eleko.waitFor( page.win, function () {
      const el = document.querySelector( 'video' )
      // wait until we can play video
      return el && el.readyState === 4 // HAVE_ENOUGH_DATA
    } )

    // evaluate with args ( play video )
    await eleko.evaluate( page.win, function ( selector, data ) {
      const el = document.querySelector( selector )

      // call the original play function
      el[ data.function_name ]()
    }, 'video', { function_name: '_play' } )

    // print video duration periodically
    tick()
    async function tick () {
      const time = await eleko.evaluate( page.win, function () {
        const video = document.querySelector( 'video' )
        return {
          currentTime: video.currentTime,
          duration: video.duration
        }
      } )

      if ( time ) {
        console.log( `${ time.currentTime } / ${ time.duration }` )
      }

      setTimeout( tick, 1000 )
    }
  }

  function containsAds ( url ) {
    return adBlockClient.matches( url )
  }

  const fs = require( 'fs' )
  const path = require( 'path' )
  const adBlockClient = require( 'ad-block-js' ).create()
  fs.readFileSync(
    path.join( __dirname, '../easylist.txt' ), 'utf8'
  )
  .split( /\r?\n/ )
  .forEach( function ( rule ) {
    adBlockClient.add( rule )
  } )

Node usage ( using launch api )

CLICK ME

  const electron = require( 'electron' )
  const eleko = require( 'eleko' )

  const fs = require( 'fs' )
  const path = require( 'path' )

  main()

  async function main ()
  {
    // make sure you have electron installed
    // npm install --save electron ( tested on 7.1.11 )
    const browser = await eleko.launch()
    const page = await browser.newPage()

    const userAgent = await page.call( 'webContents.session.getUserAgent' )
    console.log( 'userAgent: ' + userAgent )

    // cancel or do something before requests
    page.on( 'request', function ( req ) {
      const url = req.url
      const resourceType = req.resourceType

      const shouldBlock = (
        resourceType === 'image' ||
        containsAds( url )
      )

      console.log( 'url: ' + url )
      console.log( 'contains ads: ' + containsAds( url ) )

      if ( shouldBlock ) return req.abort()
      req.continue()
    } )

    console.log( ' == GIRAFFE == ' )

    const url = 'https://www.youtube.com/watch?v=Gu2pVPWGYMQ'
    await page.goto( url )

    console.log( ' == PAGE LOADED == ' )

    const now = Date.now()
    await page.waitFor( 'video' )

    await page.waitFor( function () {
      return document.title.toLowerCase() !== 'youtube'
    } )

    const title = await page.evaluate(
      function ( selector ) {
        return document[ selector ]
      },
      'title'
    )

    console.log( 'title: ' + title )
    console.log( 'waited for: ' + ( Date.now() - now ) )

    await page.waitFor(
      function () {
        const v = document.querySelector( 'video' )
        if ( v ) {
          v.pause()

          // hide play fn so that YouTube's own scripts won't
          // auto play the video
          if ( !v._play ) {
            v._play = v.play
            v.play = function () {}
          }
        }
        // wait until page can be played
        return v && v.readyState === 4 // HAVE_ENOUGH_DATA
      }
    )

    await page.evaluate(
      function () {
        const v = document.querySelector( 'video' )
        v._play()
      }
    )

    // print video duration periodically
    tick()
    async function tick () {
      const time = await page.evaluate( function () {
        const video = document.querySelector( 'video' )
        return {
          currentTime: video.currentTime,
          duration: video.duration
        }
      } )

      if ( time ) {
        console.log( `${ time.currentTime } / ${ time.duration }` )
      }

      setTimeout( tick, 1000 )
    }
  }

  const adBlockClient = require( 'ad-block-js' ).create()
  fs.readFileSync(
    path.join( __dirname, '../easylist.txt' ), 'utf8'
  )
  .split( /\r?\n/ )
  .forEach( function ( rule ) {
    adBlockClient.add( rule )
  } )

  function containsAds ( url ) {
    console.log( 'calling containsAds: ' + url.slice( 0, 55 ) )
    return adBlockClient.matches( url )
  }

About

Simple easy to use api for basic controlling of electron browser.

Why

Electron comes bundled with a nice Chromium version that is capable to play many media formats that default Chromium is unable to that e.g. Puppeteer comes with. But the API for puppeteer is much nicer.

For who?

Those wanting to easy api for basic control of the electron browser. Not intended for scraping.

How

Within electron a set of helper functions to control a BrowserWindow object.

From node using the launch api setup an IPC for a basic api.

Similar

puppeteer

puppeteer-electron

Test

test node context launch api against a local server

npm run test:node

test electron context helper functions against a local server

npm run test:electron

play youtube video test while blocking ads ( requries internet access )

npm run test:youtube

play youtube h264 video ( default chromium can't play these )

npm run test:h264

play youtube av1 video ( some wooly all-codecs chromium builds can't play these )

npm run test:av1

run all tests

npm test