Develop Reference

Discord.js loadstring

I want to make a command for a bot to evaluate a string (run it as code). Is there a way to run a string as code in discord.js? Not rly having a code sample here, I just want to know of a function to do so.

discord.js is using Node which uses Javascript, so your solution to evalute a code from a string should be with the eval() method.
Eval on developer.mozilla.org
However, as soon as you implement eval(), you'll soon find out that they have access to basically your whole computer. I would not recommend you to use this.

execute javascript from php

Sorry for this beginner question, I never used js server-side before.
here is my problem:
I have some javascript downloaded from a remote page (it's encrypted, I can't convert it to php), I need to execute it and read its output.
How can I do it? I'm thinking about something like this:
shell_exec('nodejs code...')
but how to pass the code? It's quite long, about 10 lines of javascript.
Another way would be to store the js to a file and run nodejs script.js, but that would be a useless and slow disk IO...

Important caveat about using exec/shell_exec
I feel the need to prepend a caveat about security to this answer. Always be careful when using exec or shell_exec. You almost always should not be taking data over the network to inject into a shell command for security reasons. Writing the script to a file would be much safer because there is no risk of command injection. If you are confident that this approach is required then I strongly advise you to.
Use the PHP function escapeshellcmd which will try to escape shell control characters.
Really ask yourself how much you trust the source? And how much you trust their security?
Having said that. Here's my original answer to the question as asked:
It sounds like the missing piece for your puzzle is the -e parameter for node. This will allow you to pass a script as part of the command invocation.
E.g.
C:\Users\Cmonahan>node -e "console.log('hello world');"
hello world
You can then use PHP exec or shell exec to get the output.
More information:
PHP shell_exec() vs exec()
Node CLI documentation
Edit: Regarding passing multiline arguments to the command line. This can be a bit of a minefield. For example: It depends on whether it is a Unix-like or Windows environment and then, if Unix-like, what shell is parsing the command.
See for example:
Windows: How to specify multiline command on command prompt?
End of line (new line) escapes in bash
I would recommend just making sure the argument is a single line. In the case of JS you can try minification first, which typically strips out all newlines, and see if that works for you.
Here's a popular PHP based minifier https://github.com/mrclay/minify I believe you should be able to install via composer.

dont know am not that at home with php, with isnt it true that php serves html files to the user at home, so why would it be any different from using a javascript file in a normal html page?
cant you just use:<script src="myscripts.js"></script>"
or <script>"with here your script"</script>
in the file that need to load this javascript?

How to develop a javascript library from an already existing npm module (codius)

never done this before.
I'm using https://github.com/codius/codius-host. Codiu§ development has been abandoned, but I want to salvage part of it to use for my own project. I really need to be able to run codius commands from browser, so I need to develop a library or what you call it.
var codius = require('codius')
codius.upload({host: http://contract.host}
codius-host comes packed with command-line integration,
$ CODIUS_HOST=https://codius.host codius upload
How do I make a .js script do what the command-line command does ?
also posted on https://stackoverflow.com/questions/31126511/if-i-have-a-npm-tool-that-uses-comman-line-commands-how-can-i-create-a-javascri
hard time asking this questions since don't know where to start. help.

Assuming that you have access to the codius-host source code you should find the piece of code which manages the command line arguments. I am sure that they do handle the command and the command line arguments from an entry module/function and than later delegate the real job to a different module/function. What you need to do is to provide correct parameters to the functions which the function/module that handles command line argument calls with command line parameters.
In addition to that there are some nodejs libraries that might imitate a command line call from the program itself. One of those I know is shelljs:
https://www.npmjs.com/package/shelljs
You might want to check this out as well. With this one without bothering with the source code you might be able to imitate command line behaviour.

Calling a function in a JavaScript file with Selenium IDE

So, I'm running these Selenium IDE tests against a site I'm working on. Everything about the tests themselves is running fine, except I would like to do a bit of clean-up once I'm done. In my MVC3 Razor based site, I have a JavaScript file with a function that gets a JsonResult from a Controller of mine. That Controller handles the database clean-up that Selenium IDE otherwise couldn't handle.
However, I'm having a hard time finding any sort of documentation on how to do this. I know I can do JavaScript{ myJavascriptGoesHere } as one of the Values for a line in the test, but I can't seem to find a way to tell it to go find my clean-up function.
Is it even possible for Selenium IDE to do this sort of thing?
If it comes down to it, I can just make a separate View to handle the clean-up, but I'd really like to avoid that if possible.
Thanks!

If you want to execute your own JavaScript function that exists in your test page from Selenium IDE, you need to make sure you access it via the window object. If you look at the reference for storeEval for instance, it says:
Note that, by default, the snippet will run in the context of the
"selenium" object itself, so this will refer to the Selenium object.
Use window to refer to the window of your application, e.g.
window.document.getElementById('foo')
So if you have your own function e.g. myFunc(). You need to refer to it as window.myFunc().
This can be very handy for exercising client-side validation without actually submitting the form, e.g. if you want to test a variety of invalid and valid form field values.
If you use runScript, that should already run in the window's context.

This works for me.
IJavaScriptExecutor js = driver as IJavaScriptExecutor;
string title = (string)js.ExecuteScript("myJavascriptGoesHere");
Make sure your javascript works first before using it here!

Actually to access your page javascript space, you need to get the real window of your page : this.browserbot.getUserWindow()
See this statement to get the jQuery entry point in your page (if it has jQuery of course ^^ )
https://stackoverflow.com/a/54887281/2143734

Send Javascript code to browser

Is there a way to send javascript commands to an open web running in a browser from the shell?
Let's say I have stackoverflow.com open with Chrome. Well, I'd like to send something like
alert('hi!');
from the shell, with something similar to the following:
$ send -t Chrome -w "stackoverflow.com" -c "alert('hi!')"
I was wondering this, because if I can write alert('hi!') on the javascript console of Chrome, I should be able to do the same with a call somewhere, right?
I've seen node.js but I think is not possible with that, please, let me know if I'm wrong.
I know the question could seem weird but I'm curious, thanks in advance :)

You can send JavaScript to Firefox through the jssh extension.
http://www.croczilla.com/bits_and_pieces/jssh/
This is what the Watir testing framework uses to automate Firefox.
I don't know of an equivalent for Chrome.

For IE seems like you can use good old VBScript: http://www.autohotkey.com/forum/topic7642.html
Worked for me just fine now with IE8. :)
Edit: to open this very question and alert JS value have this code as .vbs file and run it:
Dim oIE
Set oIE = CreateObject("InternetExplorer.Application")
oIE.Visible = 1
oIE.Navigate "http://stackoverflow.com/questions/4992552/send-javascript-code-to-browser/4992812"
Do While (oIE.Busy)
Wscript.Sleep 10
Loop
oIE.Navigate "javascript:alert(fkey);"

I think it is possible if you write and install some browser addon that would receive your signal, and do the job. Interesting question, ill be tracking it.

It is entirely up to the browser to provide this sort of functionality. In fact, the form of your problem isn't specific even to browsers:
I was wondering this, because if I can [provide some sort of input] to [a program] to make it [do something], I should be able to do the same with a call somewhere, right?
Some programs do indeed provide hooks for scripting, but if they don't, you're out of luck. There is certainly no guarantee that if you can do something via the GUI, then you can trigger the same action from a command line call.
Now the fact that most browsers provide some sort of plugin architecture, makes it much more likely that such a plugin exists that will listen for external input in this way, if this functionality is missing in the base product.
However, this is still going to be very specific to the particular model and even version of the browser you want to control - so if it's something you wanted to release into the wild, you'll need to be very specific with your requirements.

You can send arbitrary code to browser through the address bar! For example in AutoHotKey style，
send F6 //focus the address bar
send ctrl+v //given that your code is in clipboard
send enter
Now there is another question. Can we get the return value of the inject code? The answer is YES!
Assign your return value to document.title, and retrieve the window title from your application.
If the return value is too long (eg. a JSON format string), do the trick that
document.title='calculating...';
document.title=returnValue.subString(0,20);
sleep(10);
document.title=returnValue.subString(20,40);
sleep(10);
document.title=returnValue.subString(40,60);
...
document.title='finished';
Hope it works.