phantom

PhantomJS integration module for NodeJS

phantom - Fast NodeJS API for PhantomJS

Super easy to use

var phantom = require('phantom');
 
var sitepage = null;
var phInstance = null;
phantom.create()
    .then(instance => {
        phInstance = instance;
        return instance.createPage();
    })
    .then(page => {
        sitepage = page;
        return page.open('https://stackoverflow.com/');
    })
    .then(status => {
        console.log(status);
        return sitepage.property('content');
    })
    .then(content => {
        console.log(content);
        sitepage.close();
        phInstance.exit();
    })
    .catch(error => {
        console.log(error);
        phInstance.exit();
    });

See examples folder for more ways to use this module.

Installation

$ npm install phantom --save

How does it work?

v1.0.x used to use dnode to communicate between nodejs and phantomjs. This approach raised a lot of security restrictions and did not work well when using cluster or pm2.

v2.0.x has been completely rewritten to use sysin and sysout pipes to communicate with the phantomjs process. It works out of the box with cluster and pm2. If you want to see the messages that are sent try adding DEBUG=true to your execution, ie. DEBUG=true node path/to/test.js. The new code is much cleaner and simpler. PhantomJS is started with shim.js which proxies all messages to the page or phantom object.

Migrating from 1.0.x

Version 2.0.x is not backward compatible with previous versions. Most notability, method calls do not take a callback function anymore. Since node supports Promise, each of the methods return a promise. Instead of writing page.open(url, function(){}) you would have to write page.open(url).then(function(){}).

The API is much more consistent now. All properties can be read with page.property(key) and settings can be read with page.setting(key). See below for more example.

`phantom` object API

`phantom#create`

To create a new instance of phantom use phantom.create() which returns a Promise which should resolve with a phantom object. If you want add parameters to the phantomjs process you can do so by doing:

var phantom = require('phantom');
phantom.create(['--ignore-ssl-errors=yes', '--load-images=no']).then(...)

You can also explicitly set :

The phantomjs path to use
A logger object
A log level if no logger was specified

by passing them in config object:

var phantom = require('phantom');
phantom.create([], {
    phantomPath: '/path/to/phantomjs',
    logger: yourCustomLogger,
    logLevel: 'debug',
}).then(...)

The logger parameter should be a logger object containing your logging functions. The logLevel parameter should be log level like "warn" or "debug" (It uses the same log levels as npm), and will be ignored if logger is set. Have a look at the logger property below for more information about these two parameters.

`phantom#createPage`

To create a new page, you have to call createPage():

var phantom = require('phantom');
phantom.create().then(function(ph) {
    ph.createPage().then(function(page) {
        // use page 
        ph.exit();
    });
});

`phantom#exit`

Sends an exit call to phantomjs process.

Make sure to call it on the phantom instance to kill the phantomjs process. Otherwise, the process will never exit.

`phantom#kill`

Kills the underlying phantomjs process (by sending SIGKILL to it).

It may be a good idea to register handlers to SIGTERM and SIGINT signals with #kill().

However, be aware that phantomjs process will get detached (and thus won't exit) if node process that spawned it receives SIGKILL!

`phantom#logger`

The property containing the winston logger used by a phantom instance. You may change parameters like verbosity or redirect messages to a file with it. Note that a single logger instance is used for all phantom instances, so any change on this object will have an impact on all phantom objects.

You can also use your own logger here but you should consider providing it to the create method since logs are written inside the phantom constructor too. The logger object can contain four functions : debug, info, warn and error. If one of them is empty, its output will be discarded.

Here are two ways of handling it :

/* Set the log level to 'error' at creation, and use the default logger  */
phantom.create([], { logLevel: 'error' }).then(function(ph) {
    // use ph 
});
 
/* Set a custom logger object directly in the create call. Note that `info` is not provided here and so its output will be discarded */
var log = console.log;
var nolog = function() {};
phantom.create([], { warn: log, debug: nolog, error: log }).then(function(ph) {
    // use ph 
});

`page` object API

The page object that is returned with #createPage is a proxy that sends all methods to phantom. Most method calls should be identical to PhantomJS API. You must remember that each method returns a Promise.

`page#setting`

page.settings can be accessed via page.setting(key) or set via page.setting(key, value). Here is an example to read javascriptEnabled property.

page.setting('javascriptEnabled').then(function(value){
    expect(value).toEqual(true);
});

`page#property`

Page properties can be read using the #property(key) method.

page.property('plainText').then(function(content) {
console.log(content);
});

Page properties can be set using the #property(key, value) method.

page.property('viewportSize', {width: 800, height: 600}).then(function() {
});

When setting values, using then() is optional. But beware that the next method to phantom will block until it is ready to accept a new message.

You can set events using #property() because they are property members of page.

page.property('onResourceRequested', function(requestData, networkRequest) {
    console.log(requestData.url);
});

It is important to understand that the function above executes in the PhantomJS process. PhantomJS does not share any memory or variables with node. So using closures in javascript to share any variables outside of the function is not possible. Variables can be passed to #property instead. So for example, let's say you wanted to pass process.env.DEBUG to onResourceRequested method above. You could do this by:

page.property('onResourceRequested', function(requestData, networkRequest, debug) {
    if(debug){
      // do something with it 
    }
}, process.env.DEBUG);

Even if it is possible to set the events using this way, we recommend you use #on() for events (see below).

You can return data to NodeJS by using #createOutObject(). This is a special object that let's you write data in PhantomJS and read it in NodeJS. Using the example above, data can be read by doing:

var outObj = phInstance.createOutObject();
outObj.urls = [];
page.property('onResourceRequested', function(requestData, networkRequest, out) {
    out.urls.push(requestData.url);
}, outObj);
 
// after call to page.open() 
outObj.property('urls').then(function(urls){
   console.log(urls);
});

`page#on`

By using on(event, [runOnPhantom=false],listener, args*), you can listen to the events the events the page emits.

var urls = [];
 
page.on('onResourceRequested', function (requestData, networkRequest) {
    urls.push(requestData.url); // this would push the url into the urls array above 
    networkRequest.abort(); // This will fail, because the params are a serialized version of what was provided 
});
 
page.load('http://google.com');

As you see, using on you have access to the closure variables and all the node goodness using this function ans in contrast of setting and event with property, you can set as many events as you want.

If you want to register a listener to run in phantomjs runtime (and thus, be able to cancel the request lets say), you can make it by passing the optional param runOnPhantom as true;

var urls = [];
 
page.on('onResourceRequested', true, function (requestData, networkRequest) {
    urls.push(requestData.url); // now this wont work, because this function would execute in phantom runtime and thus wont have access to the closure. 
    networkRequest.abort(); // This would work, because you are accessing to the non serialized networkRequest. 
});
 
page.load('http://google.com');

The same as in property, you can pass additional params to the function in the same way, and even use the object created by #createOutObject().

You cannot use #property() and #on() at the same time, because it would conflict. Property just sets the function in phantomjs, while #on() manages the event in a different way.

`page#off`

#off(event) is usefull to remove all the event listeners set by #on() for ans specific event.

`page#evaluate`

Using #evaluate() is similar to passing a function above. For example, to return HTML of an element you can do:

page.evaluate(function() {
    return document.getElementById('foo').innerHTML;
}).then(function(html){
    console.log(html);
});

`page#evaluateAsync`

Same as #evaluate(), but function will be executed asynchronously and there is no return value. You can specify delay of execution.

page.evaluateAsync(function(apiUrl) {
    $.ajax({url: apiUrl, success: function() {}});
}, 0, "http://mytestapi.com")

`page#evaluateJavaScript`

Evaluate a function contained in a string. It is similar to #evaluate(), but the function can't take any arguments. This example does the same thing as the example of #evaluate():

page.evaluateJavaScript('function() { return document.getElementById(\'foo\').innerHTML; }').then(function(html){
    console.log(html);
});

`page#switchToFrame`

Switch to the frame specified by a frame name or a frame position:

page.switchToFrame(framePositionOrName).then(function() {
    // now the context of `page` will be the iframe if frame name or position exists 
});

`page#switchToMainFrame`

Switch to the main frame of the page:

page.switchToMainFrame().then(function() {
    // now the context of `page` will the main frame 
});

`page#defineMethod`

A method can be defined using the #defineMethod(name, definition) method.

page.defineMethod('getZoomFactor', function() {
    return this.zoomFactor;
});

`page#invokeAsyncMethod`

An asynchronous method can be invoked using the #invokeAsyncMethod(method, arg1, arg2, arg3...) method.

page.invokeAsyncMethod('open', 'http://phantomjs.org/').then(function(status) {
    console.log(status);
});

`page#invokeMethod`

A method can be invoked using the #invokeMethod(method, arg1, arg2, arg3...) method.

page.invokeMethod('evaluate', function() {
    return document.title;
}).then(function(title) {
    console.log(title);
});

page.invokeMethod('evaluate', function(selector) {
    return document.querySelector(selector) !== null;
}, '#element').then(function(exists) {
    console.log(exists);
});

`page#uploadFile`

A file can be inserted into file input fields using the #uploadFile(selector, file) method.

page.uploadFile('#selector', '/path/to/file').then(function() {
 
});

Tests

To run the test suite, first install the dependencies, then run npm test:

$ npm install
$ npm test