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https://github.com/binded/phantom-pool

PhantomJS resource pool based on generic-pool
https://github.com/binded/phantom-pool

nodejs npm phantomjs pool resource-pool

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PhantomJS resource pool based on generic-pool

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README 

        
# phantom-pool



[![Build Status](https://travis-ci.org/binded/phantom-pool.svg?branch=master)](https://travis-ci.org/binded/phantom-pool)



Resource pool based on [generic-pool](https://github.com/coopernurse/node-pool) for [PhantomJS](https://github.com/amir20/phantomjs-node).



Creating new phantom instances with `phantom.create()` can be slow. If

you are frequently creating new instances and destroying them, as a

result of HTTP requests for example, this module can help by keeping a

pool of phantom instances alive and making it easy to re-use them across

requests.



Here's an artificial [benchmark](./test/benchmark.js) to illustrate:



```

Starting benchmark without pool



noPool-0: 786.829ms

noPool-1: 790.822ms

noPool-2: 795.150ms

noPool-3: 788.928ms

noPool-4: 793.788ms

noPool-5: 798.075ms

noPool-6: 813.130ms

noPool-7: 803.801ms

noPool-8: 782.936ms

noPool-9: 805.630ms



Starting benchmark with pool



pool-0: 48.160ms

pool-1: 98.966ms

pool-2: 89.573ms

pool-3: 99.057ms

pool-4: 101.970ms

pool-5: 102.967ms

pool-6: 102.938ms

pool-7: 99.359ms

pool-8: 101.972ms

pool-9: 103.309ms



Done

```



Using pool in this benchmark results in an average >8x speed increase.



## Install



```bash

npm install --save phantom-pool

```



Requires Node v6+



## Usage



See [./test](./test) directory for usage examples.



```javascript

const createPhantomPool = require('phantom-pool')



// Returns a generic-pool instance

const pool = createPhantomPool({

  max: 10, // default

  min: 2, // default

  // how long a resource can stay idle in pool before being removed

  idleTimeoutMillis: 30000, // default.

  // maximum number of times an individual resource can be reused before being destroyed; set to 0 to disable

  maxUses: 50, // default

  // function to validate an instance prior to use; see https://github.com/coopernurse/node-pool#createpool

  validator: () => Promise.resolve(true), // defaults to always resolving true

  // validate resource before borrowing; required for `maxUses and `validator`

  testOnBorrow: true, // default

  // For all opts, see opts at https://github.com/coopernurse/node-pool#createpool

  phantomArgs: [['--ignore-ssl-errors=true', '--disk-cache=true'], {

    logLevel: 'debug',

  }], // arguments passed to phantomjs-node directly, default is `[]`. For all opts, see https://github.com/amir20/phantomjs-node#phantom-object-api

})



// Automatically acquires a phantom instance and releases it back to the

// pool when the function resolves or throws

pool.use(async (instance) => {

  const page = await instance.createPage()

  const status = await page.open('http://google.com', { operation: 'GET' })

  if (status !== 'success') {

    throw new Error('cannot open google.com')

  }

  const content = await page.property('content')

  return content

}).then((content) => {

  console.log(content)

})



// Destroying the pool:

pool.drain().then(() => pool.clear())



// For more API doc, see https://github.com/coopernurse/node-pool#generic-pool

```



## Security



When using phantom-pool, you should be aware that the phantom instance

you are getting might not be in a completely clean state. It could have

browser history, cookies or other persistent data from a previous use.



If that is an issue for you, make sure you clean up any sensitive data

on the phantom instance before returning it to the pool.