NAME
JavaScript::XRay - See What JavaScript is Doing
VERSION
Version 1.22
SYNOPSIS
#!/usr/bin/perl
use strict;
use warnings;
use JavaScript::XRay;
# HTML page with a <head> and <body> tag and some javascript functions
my $html_page = do { local $/; <> };
# create a new instance
my $jsxray = JavaScript::XRay->new();
# to inline/filter external javascript files you'll need 'abs_uri'
# my $jsxray = JavaScript::XRay->new(
# abs_uri => $abs_url_or_local_file_path
# );
# use switches to change filtering behavior
# $jsxray->switches( only => 'onData' );
# use inlining to inline/filter external javascript files
# $jsxray->inline_methods( 'dir1', 'dir2', \&callback, 'HTTP_GET' );
# filter page
print $js_xray->filter($html_page);
DESCRIPTION
JavaScript::XRay is an HTML source filter. It was developed as a tool to
help figure out and debug large JavaScript frameworks.
The main idea is that you hook it into your application framework and
give you the ability to 'flip a switch' an inject a JavaScript function
tracing console into your outgoing page.
Some of the things it does...
* Injects an IFrame logging console
It finds the body tag in the document and injects the IFrame just
after it along with all the JavaScript to drive it. It also provides
you with a logging function with the same name as your alias
(defaults to jsxray)
jsxray("Hi there");
* Scans HTML for JavaScript functions
For each function it finds it inserts a call to this method which
logs the function call along with the value of the function
arguments.
function sum ( x, y ) {
becomes
function sum ( x, y ) {
jsxray( "sum( " + x + ", " + y + " )" );
so now any call this function and its arguments will get logged to
the IFrame.
* Switches to limit what you log
You can manually skip specific functions, choose to see only
functions you specify, or match functions matching a specified
string. ( see the switchs methods )
* Provide execution counts
Provides a method to see how often your functions are being called.
This can be helpful to target which functions to refactor to
increase performance.
* Inlines external JavaScript files
If external javascript files are referenced, they can be inlined so
they'll be filtered as well.
* Command line script 'jsxray'
Use the command line script 'jsxray' to save and filter local HTML
files to see how things work. Think reverse engineering. :)
* Save the log for later.
You can cut and paste the IFrame to a text file to analyze later by
hand or munge the results with perl. Extremely helpful in moments
when you have a lot of code executing and your just trying to get a
handle on what's happening.
CONSTRUCTOR
JavaScript::XRay->new( %hash );
Create a new instance with the following arguments
* alias
Think of this as a JavaScript namespace. All injeted JavaScript
functions and variables are prefixed with this alias to avoid
colliding with any code that currently exists on your page. It also
is the prefix used for all the switches to toggle things on and off.
* switches
Hash reference containing switches to change filtering behavior.
Actually just dereferences the hash and passes it onto the
'switches' method.
* abs_uri
Used to help find and filter external javascript files. It can be
the absolute URL of the requested file via a webserver or the path
of the file you're filtering from the command line.
* iframe_height
The height of your logging IFrame, defaults to 200 pixels.
* css_inline
Change the style of the logging IFrame via inline CSS.
* css_external
Change the style of the logging IFrame via an external stylesheet.
* verbose
Turn on verbose output (bool)
METHODS
$jsxray->switches( %switches )
Switches control the behavior of which is going to be filtered and
provide the ability to uncomment debugging code on the fly.
* all (bool)
Turn on filtering of all functions. This is the default behavior.
all => 1
* none (bool)
Turn off filtering of functions. Helpful in combination with
uncomment switch.
none => 1
* uncomment ( string1, string2, ... )
Uncomment lines prefix with these strings. Helpful with injecting
timing code, or more specific debugging code. You can deploy
commented logging code to production and turn it on when your turn
on filtering. Extremely helpful when diagnosing problems you can't
reproduce in your development environment.
uncomment => "DEBUG1,DEBUG3"
uncomment => [ qw( DEBUG1 DEBUG3 ) ]
will turn this...
//DEBUG1 jsxray("Hey this is debug1");
//DEBUG2 jsxray("Hey this is debug2");
//DEBUG3 jsxray("Hey this is debug3");
into this
jsxray("Hey this is debug1");
//DEBUG2 jsxray("Hey this is debug2");
jsxray("Hey this is debug3");
* anon (bool)
Include filtering of anonymous functions.
anon => 1
* no_exec_count ( bool )
Don't inject code that keeps track of how many times a function was
called.
no_exec_count => 1
* only ( function1, function2, ... )
Only filter comma separated list of functions
(function1,function2,...)
only => "processData,writeToPage"
only => [ qw( processData writeToPage ) ]
* skip ( function1, function2, ... )
Skip comma separated list of functions
skip => "formatNumber,onData"
skip => [ qw( formatNumber onData ) ]
* match ( /^string/ )
Only filter functions that match string
match => 'string' # will result in qr/^string/
match => qr/whatever/
$jsxray->inline_methods( @methods );
WARNING THIS FUNCTIONALITY IS EXPERIMENTAL AND THE INTERFACE MAY CHANGE
Take external javascript blocks (use src attribute) and get the
javascript, filter it, and inline the code. There are currently three
supported methods to do this.
* HTTP_GET (default)
Special string that represents using LWP::Simple to attempt to fetch
external javascript. If the src attribute isn't absolute, then
you'll need to pass the 'abs_uri' in when you create your instance.
* File Directory
Base file path to use with the src attribute to load the javascript
off disk. From a webserver, you'd probably include the web root and
from the commandline, you'd use the path of the file you're
filtering.
* Code Reference
The arguments to the code reference are the src attribute from the
javascript attribute and the code block must return the coresponding
code.
$javascript_code = &$code_ref( $src_attr, $abs_uri );
$jsxray->filter( $html );
Pass HTML in, get modified HTML out.
AUTHOR
Jeff Bisbee, "<jbisbee at cpan.org>"
TODO
Some of the things that are still in the conceptional phase
* Personal proxy
Include a personal proxy script with this module so you can filter
ANY webpage you go to.
* Add a user interface to the console to control the switches
Add a form to the console that will allow you to see the values of
the switches and then resubmit the url to have the changes take
affect.
* Add .toSource to objects when logging (or a switch to turn it on)
BUGS
Please report any bugs or feature requests to "bug-JavaScript-xray at
rt.cpan.org", or through the web interface at
<
http://rt.cpan.org/NoAuth/ReportBug.html?Queue=JavaScript-XRay>. I will
be notified, and then you'll automatically be notified of progress on
your bug as I make changes.
SUPPORT
You can find documentation for this module with the perldoc command.
perldoc JavaScript::XRay
You can also look for information at:
* JavaScript::XRay development mailing list
<
http://groups.google.com/group/jsxray-dev>
* AnnoCPAN: Annotated CPAN documentation
<
http://annocpan.org/dist/JavaScript-XRay>
* CPAN Ratings
<
http://cpanratings.perl.org/d/JavaScript-XRay>
* RT: CPAN's request tracker
<
http://rt.cpan.org/NoAuth/Bugs.html?Dist=JavaScript-XRay>
* Search CPAN
<
http://search.cpan.org/dist/JavaScript-XRay>
ACKNOWLEDGEMENTS
* Senta Mcadoo
Providing the JavaScript DOM logging code in order to do the reverse
logging (solved the scrolling problem).
* Ronnie Paskin
General hacking on the code, good feedback, and for being a sounding
board to work out issues.
* Tony Fernandez
Giving me the green light to publish this on the CPAN.
COPYRIGHT & LICENSE
Copyright 2006 Jeff Bisbee, all rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
