phantom - Fast NodeJS API for PhantomJS
Super easy to use
const phantom = require('phantom');
(async function() {
const instance = await phantom.create();
const page = await instance.createPage();
await page.on('onResourceRequested', function(requestData) {
console.info('Requesting', requestData.url);
});
const status = await page.open('https://stackoverflow.com/');
const content = await page.property('content');
console.log(content);
await instance.exit();
})();
Using Node v7.9.0+ you can run the above example with node file.js
See examples folder for more ways to use this module.
Installation
Node v6.x and later
Latest version of phantom does require Node v6.x and later. You can install with
$ npm install phantom --save
Node v5.x
To use version 3.x you need to have at least Node v5+. You can install it using
$ npm install phantom@3 --save
Versions older than 5.x, install with
$ npm install phantom@2 --save
How does it work?
v1.0.x used to leverage 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 a shim which proxies all messages to the page
or phantom
object.
Migrating from 2.x
Going forward, version phantom@3 will only support Node v5 and above. This adds the extra benefit of less code and faster performance.
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 sitepage = null;
var phInstance = null;
phantom.create()
.then(instance => {
phInstance = instance;
return instance.createPage();
})
.then(page => {
// use page
})
.catch(error => {
console.log(error);
phInstance.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.
You can also use your own logger by providing it to the create
method. 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([], { logger: { 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 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#uploadFile
A file can be inserted into file input fields using the #uploadFile(selector, file)
method.
page.uploadFile('#selector', '/path/to/file').then(function() {
});
Advanced
Methods below are for advanced users. Most people won't need these methods.
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);
});
Pooling
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, it might be worth creating a pool
of instances that are re-used.
See the phantom-pool module for more info.
Tests
To run the test suite, first install the dependencies, then run npm test
:
$ npm install
$ npm test
Contributing
This package is under development. Pull requests are welcomed. Please make sure tests are added for new functionalities and that your build does pass in TravisCI.
People
The current lead maintainer is Amir Raminfar