NAME JavaScript::XRay - See What Your JavaScript is Doing VERSION Version 0.9 SYNOPSIS I put the comments in for lazy folks like myself who cut and page the Synopsis before they throughly read the pod. # HTML page with a
tag and hopefully some JavaScript # if you're using this module :) $html_page = ""; # the 'alias' is the prefix which all your switches will be # prefixed with and helps "scope" the injected JavaScript # variables and functions so they don't collide with # anything in your page. my $alias = 'jsxray'; # jsxray is the default # switches is just a hash ref that could be build for # incoming parameters on a query string or passed # via options via a command line script # In the future, hooks may be built for building the # switches for popular frameworks. The idea is that you # want to look through the incoming param list and pass # anything that matches your alias. This interface isn't # the cleanest, but just wanted to make it generic. It # can definately be improved... # via CGI.pm # my $q = CGI->new; # my $switches = { # map { $_ => $q->param($_) } # grep { /^$alias/ } $q->param # }; # via mod_perl # my $req = Apache::Request->new($r); # my $switches = { # map { $_ => $req->param($_) } # grep { /^$alias/ } $req->param # }; # or just hard coded to get something to work my $switches = { $alias => 1 }; # or if you only one to see functions matching '/^ajax/' my $switches = { $alias => 1, $alias . "_filter" => 'ajax' }; # now we only want to filter if its turned on so we can # you may want put your switch building inside this # conditional as well and just check for your alias if ( $switches->{$alias} == 1 ) { my $js_xray = JavaScript::XRay->new( alias => $alias, switches => $switches, ); $html_page = $js_xray->filter($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 out going page. Some of the things it does... * Injects a IFrame "log" 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 method (whatever you used as alias - defaulted to jsxray). jsxray("Hi there"); * Scans HTML for JavaScript functions For each function it finds it inserts 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 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 filter functions matching a specified string. ( see SWITCHES ) * Provide execution counts Provides a method to see how often your functions are being called. This can be helpful to target which functions to rewrite to increase performance. * 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. SWITCHES The module's initial design was for it to be used via a query string and the switches evolved from there. (In other words, if this switch interface feels clunky, thats the reason why) Also not the below examples use the alias 'jsxray' but if you use a custom alias, the urls with change accordingly. * uncomment Uncomment lines prefix with these strings (string1,string2) 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. Extremly helpful when diagnosing problems you can't reproduce in your development environment. http://someurl/somepage?jsxray=1&jsxray_uncomment=DEBUG1,DEBUG2 will uncomment //DEBUG1 jsxray("Hey this is debug1"); //DEBUG2 jsxray("Hey this is debug2"); * anon (bool) Include filtering of anonymous functions. (bool) http://someurl/somepage?jsxray=1&jsxray_anon=1 * no_exec_count Don't inject code that keeps track of how many times a function was called. (bool) http://someurl/somepage?jsxray=1&jsxray_no_exec_count=1 * only Only filter comma seperated list of functions (function1,function2,...) http://someurl/somepage?jsxray=1&jsxray_only=processData,writeTopage * skip Skip comma seperated list of functions (function1,function2,...) http://someurl/somepage?jsxray=1&jsxray_skip=formatNumber * skip Only filter function that match string (/^string/) http://someurl/somepage?jsxray=1&jsxray_filter=ajax CONSTRUCTOR new Create a new instance with the following arguments * alias Think of this as a JavaScript namespace. All injeted JavaScript fuctions and varibles 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 behavor. See the "Switches" section for more details. * 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. METHODS filter INTERNAL METHODS _inject_js_css Hook to inject the alias prefixed JavaScript and CSS into the page. _inject_console Hook to inject HTML and the IFrame into the page. _css Hook to inject alias prefixed CSS into the iframe and page. _init_switches Take alias prefixed switched passed in and strip off the alias and make them easier to call. _warn Hook to warn to the JavaScript IFrame log. AUTHOR Jeff Bisbee, "