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Is there a way to debug page.open method of phantomjs ? My application loads some files saved locally but unfortunately the only info one can get when opening the page is if it was loaded successfully or not. What more interesting the very same page loads properly when opened in the browser.

Here's my code :

var system = require('system'),
    page   = require('webpage').create(); 

var openPage = function () {

    var url = 'http:\\localhost:53794/file.html';

    page.open(url, function (status) {
        if (status !== 'success') {
            console.log("FAIL:" + url);
            phantom.exit(2);
        }

        var date            = new Date().getTime();
        var outputFilename  = outputPath + 'print-' + date + '.png';

        setTimeout(function () {
            page.render(outputFilename);
            outputArray.push(outputFilename);

            setTimeout(function () {
                phantom.exit(1);
            }, 1);
        }, 1);        
    });
}

openPage();

Is there a way to debug page.open method of phantomjs ? My application loads some files saved locally but unfortunately the only info one can get when opening the page is if it was loaded successfully or not. What more interesting the very same page loads properly when opened in the browser.

Here's my code :

var system = require('system'),
    page   = require('webpage').create(); 

var openPage = function () {

    var url = 'http:\\localhost:53794/file.html';

    page.open(url, function (status) {
        if (status !== 'success') {
            console.log("FAIL:" + url);
            phantom.exit(2);
        }

        var date            = new Date().getTime();
        var outputFilename  = outputPath + 'print-' + date + '.png';

        setTimeout(function () {
            page.render(outputFilename);
            outputArray.push(outputFilename);

            setTimeout(function () {
                phantom.exit(1);
            }, 1);
        }, 1);        
    });
}

openPage();

• javascript
• phantomjs

Share Improve this question Follow edited Dec 31, 2012 at 11:50 mike_hornbeck asked Dec 31, 2012 at 10:44 mike_hornbeckmike_hornbeck 1,62233 gold badges3030 silver badges5252 bronze badges 4

• 'http:\\localhost:53794\file.html' is not how you write a valid http URL. – Werner Kvalem Vesterås Commented Dec 31, 2012 at 10:50
• What do you mean ? to use 127.0.0.1 instead of localhost ? – mike_hornbeck Commented Dec 31, 2012 at 11:07
• No, I am talking about the format of the URL. – Werner Kvalem Vesterås Commented Dec 31, 2012 at 11:11
• looks like you were right, reversing the slashes fixed the problem. Please add this as an answer so that I can accept it. – mike_hornbeck Commented Dec 31, 2012 at 12:25

Add a ment  | 

2 Answers 2

Sorted by: Reset to default 8

via: http://newspaint.wordpress./2013/04/25/getting-to-the-bottom-of-why-a-phantomjs-page-load-fails/

After creating the page variable, but before calling page.open() add the following code:

page.onResourceError = function(resourceError) {
    page.reason = resourceError.errorString;
    page.reason_url = resourceError.url;
};

Now you can print out the reason for a problem in your page.open() callback, e.g.:

var page = require('webpage').create();

page.onResourceError = function(resourceError) {
    page.reason = resourceError.errorString;
    page.reason_url = resourceError.url;
};

page.open(
    "http://www.nosuchdomain/",
    function (status) {
        if ( status !== 'success' ) {
            console.log(
                "Error opening url \"" + page.reason_url
                + "\": " + page.reason
            );
            phantom.exit( 1 );
        } else {
            console.log( "Successful page open!" );
            phantom.exit( 0 );
        }
    }
);

Debugging Function

If you read further down the blog, he has some more suggested event handlers to add. I adapted them into a function that you can use to inject the event handlers into your page object (instead of having them defined in your main code)

// this method injects some debugging event handlers 
// into a PhantomJS page object.
// usage:
//   var page = require('webpage').create();
//   var system = require('system');
//   addDebugEvents(page,system);
function addDebugEvents(page, system) {

    page.onResourceError = function (resourceError) {
        page.reason = resourceError.errorString;
        page.reason_url = resourceError.url;
    };

    page.onResourceRequested = function (request) {
        system.stderr.writeLine('= onResourceRequested()');
        system.stderr.writeLine('  request: ' + JSON.stringify(request, undefined, 4));
    };

    page.onResourceReceived = function (response) {
        system.stderr.writeLine('= onResourceReceived()');
        system.stderr.writeLine('  id: ' + response.id + ', stage: "' + response.stage + '", response: ' + JSON.stringify(response));
    };

    page.onLoadStarted = function () {
        system.stderr.writeLine('= onLoadStarted()');
        var currentUrl = page.evaluate(function () {
            return window.location.href;
        });
        system.stderr.writeLine('  leaving url: ' + currentUrl);
    };

    page.onLoadFinished = function (status) {
        system.stderr.writeLine('= onLoadFinished()');
        system.stderr.writeLine('  status: ' + status);
    };

    page.onNavigationRequested = function (url, type, willNavigate, main) {
        system.stderr.writeLine('= onNavigationRequested');
        system.stderr.writeLine('  destination_url: ' + url);
        system.stderr.writeLine('  type (cause): ' + type);
        system.stderr.writeLine('  will navigate: ' + willNavigate);
        system.stderr.writeLine('  from page\'s main frame: ' + main);
    };

    page.onResourceError = function (resourceError) {
        system.stderr.writeLine('= onResourceError()');
        system.stderr.writeLine('  - unable to load url: "' + resourceError.url + '"');
        system.stderr.writeLine('  - error code: ' + resourceError.errorCode + ', description: ' + resourceError.errorString);
    };

    page.onError = function (msg, trace) {
        system.stderr.writeLine('= onError()');
        var msgStack = ['  ERROR: ' + msg];
        if (trace) {
            msgStack.push('  TRACE:');
            trace.forEach(function (t) {
                msgStack.push('    -> ' + t.file + ': ' + t.line + (t.function ? ' (in function "' + t.function + '")' : ''));
            });
        }
        system.stderr.writeLine(msgStack.join('\n'));
    };

}

You should change the URL

from

http:\\localhost:53794/file.html

to

http://localhost:53794/file.html

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