Properties are undefined inside of evalute in PhantomJS

Question

I'm fetching an website's content via phantomjs by including jquery with the page. Now i have to write them to a file via program. For that i used the following code

page.onLoadFinished = (function(status) {
    if (status === 'success') {
        page.includeJs('http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js', function() {
             page.evaluate(function() {

                var mkdirp = require('mkdirp');
                mkdirp(counter+'_folder', function(err) { 
                    var html = $('pre[data-language="html"]').html();
                    var js   = $('pre[data-language="js"]').html();
                    var css  = $('pre[data-language="css"]').html();    
                    var fs = require('fs');
                    fs.writeFile(counter+"_folder/"+"fiddle.html", html, function(err) {}); 
                    fs.writeFile(counter+"_folder/"+"fiddle.css", css, function(err) {}); 
                    fs.writeFile(counter+"_folder/"+"fiddle.js", js, function(err) {}); 
                    console.log("******* "+counter+" *************");
                });
            });
        });
    }
});

page.open(url[counter]);

Now what happening is inside evalute method when I'm using require the program is getting stopped there showing error cannot find variable require. Any idea why this is appering?

score 1 · Answer 1 · edited May 23 '17 at 11:51

page.evaluate() is the sandboxed page context. It has no access to require, page, phantom ...

Furthermore, mkdirp is a node module which will not work with PhantomJS. If you want to use PhantomJS from node, you will have to use a bridge like phantom. See also: Use a node module from casperjs

Using that bridge, you have to pass the variables to the outside and save it from there:

page.open(url, function(){
    var mkdirp = require('mkdirp');
    mkdirp(counter+'_folder', function(err) { 
        page.evaluate(function() {
            var html = $('pre[data-language="html"]').html();
            var js   = $('pre[data-language="js"]').html();
            var css  = $('pre[data-language="css"]').html();    
            return [html, js, css];
        }, function(result){
            var fs = require('fs');
            fs.writeFile(counter+"_folder/"+"fiddle.html", stuff[0], function(err) {}); 
            fs.writeFile(counter+"_folder/"+"fiddle.css", stuff[1], function(err) {}); 
            fs.writeFile(counter+"_folder/"+"fiddle.js", stuff[2], function(err) {}); 
            console.log("******* "+counter+" *************");
        });
    });
});

Note: PhantomJS' fs module doesn't have a writeFile function. Node and PhantomJS have different execution environments.

Properties are undefined inside of evalute in PhantomJS

1 Answers1