Can anybody explain me, How greasemonkey runs a user script?
I am looking forward to know the technical details i.e, How and where the script is read and run, at gresemonkey or on the browser?How the interaction between greasemonkey and browser takes place?
I know how to install the scripts.
Basically I am using Greasemonkey for IE and IE8.
Thank you
The source code is available on github and Mozilla have extensive documentation on writing add-ons.
… ah, you're talking about "Greasemonkey for IE" and not "Greasemonkey". The source code is still available, just in a different place, was still available when this question was asked but it looks like the project has since died. I bet MSDN will have equivalent docs somewhere.
Related
I am working on a project in my company and I have to decide on whether to build a web application or a firefox add on that would be then published.
The major motivation behind building a firefox addon is being able to call functions inside other add ons.
Excuse me if I am saying something stupid, I have no experience with firefox or add ons and couldn't find anything useful. I would be very grateful for any information, or even a hint on where to start my research.
Thank you very much for your answers.
Answer 1 is more of an old-school approach to building add-ons for Firefox. There is a newer, more web-like api Mozilla has been working on called the Add-on SDK:
https://addons.mozilla.org/en-US/developers/docs/sdk/latest/dev-guide/tutorials/index.html#getting-started
This is the place you need to go if you need information on building Firefox addons or extensions
https://developer.mozilla.org/en-US/docs/Building_an_Extension
And MDN docs are one of the most complete docs for JavaScript, which you will be using a lot for the extension. Most of your doubts should be cleared there.
I'd like to develop an Internet Explorer extension that changes the content of a specific webpage, like content scripts in Google Chrome. (eg. when I go to the website Google and I search for "car" I'd like to have a div created on the page with the word "car" inside).
I've been looking on SO but haven't found clear evidences if this kind of thing is possible.
What I'm specifically looking for is a clear tutorial or some example of how to do this.
Bruno,
That is exactly what GreaseMonkey for IE is made for http://www.gm4ie.com/
I have answered a similar question, but the answer is in C#. It describes how to create a fully working project to accomplish exactly what you asked: changing page contents!
How to get started with developing Internet Explorer extensions?
It covers other topics too:
running javascripts from the addin
how to register IE addins
saving data (addin configurations)
You can read more about Internet Explorer Extension from MSDN:
http://msdn.microsoft.com/en-us/library/aa753587(v=vs.85).aspx
Extensions in IE are not created using web technologies, they are created using C++/.NET. Such as ActiveX
Similar to "GreaseMonkey for IE" is Trixie:
Trixie is to Internet Explorer as Greasemonkey is to Firefox. It lets you remix the Web via scripts. You may do this to either make it more readable, fix bugs or to even add little features to make the site more usable to you. Trixie by itself does none of this. It is just a plugin for Internet Explorer that enables executing chunks of JavaScript code and thus lets you use the Web the way you want to use it.
This is one of the best I found. http://www.enhanceie.com/ie/dev.asp It has give sample scripts as well. Which will help you.
Another one is open source and stable version : firebreath
same kind question is also asked How to get started with developing Internet Explorer extensions?
This is a working example of manipulating the DOM from microsoft. This is a BHO development with MS Visual Studio. Check it out: http://msdn.microsoft.com/en-us/library/bb250489%28v=vs.85%29.aspx
I'm pretty new to workign with Javascript.
In most languages you can run the code quickly locally on your machine. From what I've seen, in JS you generally only use it via the browser, and so I've been uploading my code an viewing its effects in the browser. This has proven very tiresome. Also, if I mak one error, it seems like my JS/JQuery will just do NOTHING, instead of giving me a useful error, message, which is making it painfully slow to code in.
IS there some way to run JS locally to see that it is working as I go? And then only upload it to the web when I'm mostly done? What ways are there for me to do this? What ways aer there for me to unit test the Javascript locally? Say I have some JAML that should render as <p>HI</p>, how do I run this locally in a unit test?
Thanks for the help,
Alex
EDIT:
Thanks for all the great suggestions. I'll have to take a bit of time and go through them to see which ones best help me in my situation.
Since you're using jQuery, I assume that you actually want to manipulate the various elements on your page. So depending on your specific development enviroment, uploading it each time is probably the way to go anyway. If you can set up a dev enviroment on your local machine (not always possible) then go with that.
As an actual answer to your question, I suggest using Chrome's developer tools, it doesn't just have the console, but an element inspector, and a resource tracker (resource tracker is invaluable when working with JSON and AJAX, since invalid json will fail silently)
As far as I know, the firebug plugin for firefox (dont use it myself) has a similar feature set, so if you're more comfortable with that go with it.
Just remember, as a developer, your development (and debuggin) enviroment is just as important as the code that you are writing.
EDIT: Noticed that you mentioned unit testing. There are several unit testing frameworks out there for JS including one that integrates with firebug called FireUnit. Do a quick google search to find more if you want.
You don't need to upload the JS file to a server to test it. Just write an html and declare the js binding
<script
src="js/yourJSFile.js"
type="text/javascript"></script>
Edit the JS file in your favorite editor and then refresh the page to test it.
For unit testing the best option is Selenium. It allows you to record an interaction with the browser and then play it back.
You can use Firebug with Firefox to debug JS, and Google Chrome has a debugger built-in (use the Tools -> Developer Tools menu).
You can run Javascript from the local file on your machine in your browser, so you can skip the uploading step.
Also, I'd recommend using Firefox/Firebug combo for developing Javascript as it will be very handy, especially for the part you mentioned about not seeing what's going wrong with your code.
Even if you upload your javascript it gets downloaded back to you as soon as you visit the webpage that invoques it. Its run client side always. So stick to local and use firebug as the others have said. Google`s developer tool is quite nice too.
In the browser if you open the developer tools, follow the following steps:
1) Navigate to sources
2) Under sources, click snippet and open run.js
3) You can use run.js to write as much code as you want and run it locally only to see if your code is working or not (it will give you output on the console)
4) Also you can get used to some keyboard shortcuts to make it faster for you.
5) For small javascript codes, you can navigate to console and run your code there
If you want to do unit testing with Javascript there are extension of Firebug that can help you with that. I haven't try any of them, so I can't really tell you which one are worth considering, but you can easily find them if you search for the keyword "Firebug unit testing" on Google.
What seems to be comming on top is FireUnit. You can find some information about how it works here.
Consider Spider Monkey, which is a javascript engine separate from a browser. If what you are developing does not involve rendering to a webpage or can be separated from the rendering code (good practice!), then this could be useful.
I prefer Chrome to Firefox and I just found Web Server for Chrome.
It's just a Google App that quickly sets up a web server for you and will be set up anywhere you are logged into Chrome. It only allows file access to your current devices, or if you specify, other devices only on the current LAN.
You just point it to the directory with your index.html file and type http://127.0.0.1:8887 in your browser.
Additionally to the answers given you can use Jasmine for automated testing.
A tutorial that seems to help get started with automated testing on Jasmine is provided by Evan Hahn.
I used it and for me it works like a charm. Especially if test driven development is what you are going for!
Just as we have http://www.sliver.com/dotnet/SnippetCompiler/ (link inactive on 2021-04-24) to test a C# code quickly, I can also do the same for javascript in chrome debugger tools and Firebug (firefox).
I would be more interested in a tool or some online tool which can run a small piece of javascript and tell if it properly runs in prominent browsers and the result.
UPDATE:
I'm a developer and not tester. I don't want to install all browsers on my PC. I like chrome and I can debug/test (for syntax/result) almost every javascript quickly in chrome by just clicking Ctrl+Shift+J and pasting my javascript in its console. But that will just test if it works in chrome. I'm not interested in creating a library right now. Google and Stackoverflow helps me get the greatest and latest javascript for a specific task very quickly.
I found one way. But it is not that quick and still would like to know better answer. May be some kind of tool which can do this.
One Way:-
Write your javascript enclosed in try-catch block on JsBin and create its public link. Now check your link with BrowserShots.
Write considerable amount of html (conditionally) using javascript to be able to see the difference on Images given by BrowserShots.
To propose another option 10 years down the line: I would suggest using JSHint for this.
The first page as you navigate to their site allows you to simply paste a JS snippet and get information regarding everything from potentially confusing syntax to "minimum ES version" warnings.
Furthermore, you can also install JSHint to your project and have a command to either run manually or slot into your existing build chain to do the same thing locally with custom rules.
I've also found this tool: JS Compatibility Checker, which is based on Can I use.
Could be helpful, but won't outline every issue.
You can easily make a test page to house your snippets, then try them in your target browsers. That has the added advantage of providing a central library for the snippets you do create, so you don't have to go hunting through entire directories looking for that cool little widget you created back in 2010.
Also, you can check the MDN Web Docs Browser Compatibility section if that interface is available (Eg. window.location - https://developer.mozilla.org/en-US/docs/Web/API/Location#browser_compatibility)
Firefox has the Sandbox and evalInSandbox(). Chrome has sandboxed execution in their content scripts (they call it isolated execution). I'm looking for the same thing in an IE browser extension.
I can load a javascript file, then call evalScript(), but the code executes in the same environment as javascript that exists on the page. I need a way to run my library (which includes and is based on jQuery) in an sandboxed/isolated environment, but still allow it to modify the DOM as if it were running on the page.
Jint looks promising, but cannot currently evaluate jQuery. (They can parse it.)
How can I do this?
Looks like you are in a pickle with this one.
Some Microsoft people say that IE doesn't offer this functionality
Some who say they have been able to pull this off hold it close and protect it as their secret sauce
"Professional" IE extension shops, when contacted about building what you are talking about turn down the job
I really wish I had better news but it looks like it might take a small miracle to accomplish what you are looking for... or maybe a lot of money. : )
Your best bet is probably going to be finding one of the few who claim they have been able to do it and pay them a lot to share the secret or reconsider why you really want what you want and see if you can't accomplish it another way.
You might find it worthwhile looking at the Microsoft Web Sandbox at the Live Labs:
http://websandbox.livelabs.com/
Although it's more fully fledged and related to mashups and the like it might point you in the right direction.
Thing you are looking for is ActiveScript engine (http://en.wikipedia.org/wiki/Active_Scripting)
I can`t find any usefull links now, MSDN contains only interfaces definition (http://msdn.microsoft.com/en-us/library/ccd0zt2w(v=vs.85).aspx)
Try to Google "Active Scripting" (not "Action scripting"!)
You need to implement interface IActiveScriptHost in your extension, create an object of «JScript», call SetSite and pass your host object, then you can load your js code into this engine and run it.
This technique is a quite difficult due to lack of documentation about it.
If you are still interested in this, I can send you some examples in C++/ATL.
Can you elaborate on your goals a bit?
I don't think you've clearly defined what you're trying to accomplish. If your code has the ability to modify the page's DOM, then it effectively is executing in the context of the page. It can create new script blocks to perform any unsafe or unreliable action that it could accomplish were it operating in the same execution environment.
IE doesn't offer a feature to do what you're asking, and I'm not convinced that the Firefox and Chrome features work the way that you expect that they do.