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How to load large JSON file into javascript

Firstly, thanks for taking time to view my post. I am working on a project with a few people, and we basically have a webpage, and once you log in, it displays all the data from a mysql database which has 6 tables, 3 of which have data in them. We figured out that in order for us to go about this, we need to transfer data by exporting the data into JSON file(s), then from there load the JSON files into java script so it can communicate with the web server. We were wondering what would be the best way to go about this. One way we found out is to reference the JSON ddata as variables and just list everything out, but several of our files have loads and loads of data. Would there be an easier approach?
This would be the first time we are doing something like this, so we are learning and appreciate your feedback!!

If you're using some kind of AJAX library, you can easily request the .json file from the browser.
For example with jQuery:
$.post("ourJSONFile.json", function( data ) {
..logic to display data..
});

NOTE - The comment about no PHP was not posted while I was writing this. Until I know why there can be no PHP, I'm just going to leave this answer here.
I think you're going at this in the wrong way. There is no need for JSON here, just query your database for the information.
The overview of what you need to do is (in PHP or the language you use to talk with your server) you need to
connect to the database
query database for information (query in your case, more or less means get the information)
do something with the returned information (such as echoing it in PHP so it will go to the user)
Now, it doesn't look like there is much effort place for getting this done, only planning. So, I'll just show you a few links to read up. (Which is also why people has devoted your question, Stackoverflow doesn't like asking question with no effort to research answers)
I'd use php.net for looking up methods, such as the mysqli_query method. This is very useful for learning small but important things about the method, like what it returns when an error occurs.
http://php.net/manual/en/mysqli.query.php
Taking a quick look through this guide, I think it should suffice. Besides syntax and such, some other important points are use MySQLI (when using PHP 5 or higher) and use prepared statements.
http://www.pontikis.net/blog/how-to-use-php-improved-mysqli-extension-and-why-you-should
The use of prepared statements is to protect your queries from injections. w3schools gives a good explanation about this # http://www.w3schools.com/sql/sql_injection.asp
MySQLI is MySQL Improved, it is more secured and supported. MySQL has been deprecated since PHP 5, and php.net pages on a MySql method will actually say this at the very top.
Finally, Andrew mentioned AJAX. AJAX is (for example) a way of doing things that would normally require reloading the page, without reloading the page. There is more to that, and I would recommand looking into it once you get use to the languages you are using.
Note, AJAX does not require libraries to use, it can be done with pure javascript. Libraries simply (as seen around) simplify AJAX a lot.

How to create a truly hidden variable in Javascript

I am trying to build a puzzle game using HTML & JS. This is going to be a standalone HTML page. There isn't going to be a server side for this application.
Obviously, the game has an answer which the application will create at start time. Now, I wish to make this variable completely hidden i.e., not just hidden from user's view but also inaccessible to the user, even if he tries to read the page through Chrome's Developer Tools or such debug tools.
I'm looking for a solution using HTML5, JS ECMAScript 5+ & jQuery.
I remember reading something about Native HTML code (used for HTML File elements) which cannot be rendered/read even through Dev Tools. Is this any help?
Is there any way or strategy to achieve this?
NOTE: I am aware of <input type="hidden">. But that doesn't serve my purpose.
EDIT: As part of the game, the user makes attempts and the application needs to validate the user's input against this somehow-user-hidden answer variable. At this point, I believe there is no solution that's going to be completely airtight in the given constraints. Hence, I'm pursuing this from an academic interest. Does anyone have any other answers ?

Prehash your answer, hard code that into your page.
Then, when they submit their answer, run through whatever hashing pattern you did before hand, and compare the result.
It could theoretically be brute forced, of course.... if you had a few hundred years.
Javascript implementations of:
SHA-1: http://www.webtoolkit.info/javascript-sha1.html
SHA-256: http://www.webtoolkit.info/javascript-sha256.html
MD5: http://www.webtoolkit.info/javascript-md5.html
Edit:
An example would be:
Pattern: SHA-1(SHA-1(SHA-1(answer + salt)))
Salt: 982qx17wef7ddsbtxaewnsdufs (make something up, load it as an input type='hidden')
Result: (load it as an input type='hidden')
Request the answer
If SHA-1(SHA-1(SHA-1(attempt + salt))) === Result, they got it correct

Your can hash your values using MD5.
https://github.com/blueimp/JavaScript-MD5#client-side

Ajax applications with perl backend - how to?

There are already questions about the Perl+AJAX, like here, here or here and several others. They're more than 2 years old and I was hoping for some new stuff.
The questions are:
What is the most preferred method today making AJAX apps with a Perl backend?
Are there some active and commonly used Perl modules that help build AJAX based applications?
Something, for the usual workflow:
if clicked this button (or changed this field.. etc),
POST these data to the server,
read the JSON answer,
and update this/these DIV(s) in a DOM... etc.
This question is can be classified as vague, but I'm really lost and need help with this: what is the most common way making AJAX apps in the Perl world, TODAY.
Looking for a helper module that help me build the browser-side javascript.
I found these:
https://metacpan.org/pod/OpenThought
https://metacpan.org/pod/HTML::AjaxTags
https://metacpan.org/pod/CGI::Ajax (but this is CGI based and IMHO not the best for Plack world)
These modules have not been updated for several years. Are they stable and in use? Or are they deprecated and is there some better way? (for the modern Perl technologies - like Plack).
UPDATE
As I read answers, I'm thinking that the main problem is probably in my English. I don't know how to express myself right.
I know Perl. Maybe I'm not an expert, but I wrote several thousand lines of code. I know Dancer, and already write some apps in Mojo...::Lite. Know JSON{::XS} and I know how AJAX works.
Now (for some reason) I prefer using Mason2, with Mason::Plugin::RouterSimple and several other CPAN modules and Moose. Catalyst, Jifty are too big for my needs.
Back to the question:
My favorite JS framework is jQuery, I'm using it in several projects for modal windows, or accordions, tabs etc.
BUT
My main problem is exactly in Sismetic's answer. I don't want to write JavaScript. Don't like it. (Don't know it very well, and hate every language where I must write something like: var arr = new Array(); instead of my #arr)
So, looking for a solution, how I can minimize (or in the ideal world - totally eliminate) the need of writing the JavaScript code. Don't want write into my templates
$('.clickableButton').click(function(e) {
.... etc... etc..
)}
but something like:
$ajax->make_button( -onchange=>$url, -updatedom=>'#thisdiv", some_special_button_description_in_perl );
$tohead .= $ajax->gen_libs();
$tohtml .= $ajax->gen_html();
$jsdocready .= $ajax->gen_jsinitcode();
An in my templates will output only $tohead in the head part (so include jQuery), $tohtml will come into body, and $jsdocready will come into the end of body as JavaScript init code.
Offcourse, the above is an very stupid example, but hopefully shows what I mean. Simply: The ideal solution was (probably does not exists) is totally eliminate the need writing JavaScript, only Perl code what will generate the needed JS.
Therefore I mentioned the above modules, especially https://metacpan.org/pod/OpenThought, because these really help minimize writing JavaScript. The problem is - these have not updated for 2 years. ;( And unfortunately - I don't know any others.

The reason you're not getting answers isn't just the vagueness of the question. The problem space is very wide and has a many angles of attack.
Let's clarify that the "x" in Ajax shouldn't be taken to mean XML anymore. JSON is obviously more natural and doesn't suffer from nearly as many problems so all my advice will point toward it.
What hobbs said already is right on. You do not want to mess with the server-side code much at all but adopt a framework. This is not because dealing with Ajax is hard in Perl; it's trivial. It's because the problem space gets messy quickly and you'll end up repeating your code in endless minor variations. So–
Perl/Server-side
Any of these will make you happy eventually. They all have a learning curve. There are other options but these are the Best™.
Catalyst (Catalyst::View::JSON)
Dancer (Dancer::Serializer::JSON)
Mojolicious (prefer Mojolicious for HTML5/Websockets)
Deployment SHOULD be Plack/PSGI based.
Take the time to really learn the core of Perl's Ajax handling: JSON(::XS) so you know what the views in the various frameworks do under the covers.
JavaScript/Client-side
This is essentially an embarrassment of riches at this point.
jQuery
Many Perl hackers like this kit; it seems to hit the same sweet spot Perl does. I adore jQuery.
Dojo
I'm not a fan — they had the worst documentation possible in early versions and broke compatibility while deleting what little docs used to exist — but it's well-liked in its current version.
MochiKit
MooTools
YUI
ExtJS
This, now distant, fork from YUI is the 800lb gorilla of client-side JS. I personally dislike it because of its lack of graceful degradation, et cetera, but it is highly regarded and very sharp looking out of the box.
I personally dislike and can't recommend prototype and though I've never used it I also chose not to put script.aculo.us on the list.
There are plenty of other amazing specialty kits out there too; e.g., Modernizr. When you are looking into JS, consider how important standards compliance and forward-looking features like CSS3, HTML5, extended event handling like multi-touch are to what you'll do. Good luck and have fun.
Update: Possibly of further interest
Jemplate – templating in JavaScript
Catalyst::View::Jemplate
Jifty – YAWF

Looking for "ajax" isn't really what you need. Just use a web framework of your choice that has good facilities for serialization, working with Accept headers, etc. For example Catalyst and Catalyst::Action::REST, or Dancer. Don't write Perl that writes Javascript, it will only make you sad.

I use CGI::Application as my base framework and CGI::Application::Plugin::JSON to return JSON data to jQuery.

If you want to generate HTML code with a Perl module, I would recommend CGI.pm:
...
use strict;
use warnings;
#CGI is shipped along perl, I think
use CGI;
my $CGI = CGI->new();
my $return_string = '';
#From CGI documentation on CPAN
#http://search.cpan.org/~markstos/CGI.pm-3.55/lib/CGI.pm
$return_string .= $CGI->header;
$return_string .= $CGI->start_html('hello world');
$return_string .= $CGI->h1('hello world');
$return_string .= $CGI->button(-name => 'button_name',
-value => 'Click Me!',
#Javascript event if needed
-onClick => "do_something()"
);
$return_string .= $CGI->end_html;
print $return_string;
Or(as I dont like the latter method) you could just write it on perl(generating it yourself manually):
use strict;
use warnings;
#Needed header, otherwise will return error
print "Content-type: text/html\n\n";
#return random number from 0 to 100
my $random_number = int(rand(101));
my $HTML_generated_string = qq|
<html>
<head>
<title>HTML generated manually with perl</title>
</head>
<body>
<h1>Hello world</h1>
Bla bla bla Heres the random number $random_number
</body>
</html>
|;
print $HTML_generated_string;
Other than that, I dont know any extra modules to do it. I normally do it by hand, or write a template(with CGI::Application).

I don't think the thing you are asking for exists. You can't write AJAX apps without using JavaScript. If someone invented a way to do JavaScript without JavaScript it would be a major project and not one person's weekend CPAN module.
I suggest rethinking your view of JavaScript. JavaScript is an excellent language and JQuery is great as well. There is a lot of bad JavaScript code out there, but there is good JavaScript code as well. Just like there are good and bad practices in the Perl community. I'd suggest you keep an open mind and take another look at JavaScript and make sure you really know the foundations well. Sometimes my frustration with a language just means I haven't learned it very well.
There are some very cool things happening in the JavaScript world. I admit its chaotic and decentralized and there is a lot of different stuff to know about and thats exhausting but its also exciting that so much is happening.
You probably already know about these resources, but just in case: FireBug, Mozilla Developer Network JavaScript docs, and JavaScript Garden

See Dancer::Plugin::Ajax on cpan
http://metacpan.org/pod/Dancer::Plugin::Ajax

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.

How can I execute javascript in Bash?

I try to get to a page straight from Bash at http://www.ocwconsortium.org/. The page appears when you write mathematics to the field at the top right corner. I tested
open http://www.ocwconsortium.org/#mathematics
but it leads to the main page. It is clearly some javascript thing. How can I get the results straight from Bash on the first page?
[Clarification]
Let's take an example. I have the following lines for a Math search engine in .bashrc:
alias mathundergradsearch='/Users/user/bin/mathundergraduate'
Things in a separate file:
#!/bin/sh
q=$1
w=$2
e=$3
r=$4
t=$5
open "http://www.google.com/cse?cx=007883453237583604479%3A1qd7hky6khe&ie=UTF-8&q=$q+$w+$e+$r+$t&hl=en"
Now, I want something similar to the example. The difference is that the other site contains javascript or something that does not allow me to see the parameters. How could I know where to put the search parameters as I cannot see the details?

open "http://www.ocwconsortium.org/index.php?q=mathematics&option=com_coursefinder&uss=1&l=&s=&Itemid=166&b.x=0&b.y=0&b=search"
You need quotes because the URL contains characters the shell considers to be special.

The Links web browser more or less runs from the commandline (like lynx) and supports basic javascript.
Even though the title of the post sounds general, your question is very specific. It's unclear to me what you're trying to achieve in the end. Clearly you can access sites that rely heavily on javascript (else you wouldn't be able to post your question here), so I'm sure that you can open the mentioned site in a normal browser.
If you just want to execute javascript from the commandline (as the title suggests), it's easy if you're running bash via cygwin. You just call cscript.exe and provide a .js scriptname of what you wish to execute.

I didn't get anything handled by JavaScript - it just took me to
http://www.ocwconsortium.org/index.php?q=mathematics&option=com_coursefinder&uss=1&l=&s=&Itemid=166&b.x=0&b.y=0&b=search
Replacing mathematics (right after q=) should work. You may be able to strip out some of that query string, but I tried a couple of things and and it didn't play nice.
Don't forget to encode your query for URLs.

You will need to parse the response, find the URL that is being opened via JavaScript and then open that URL.

Check this out: http://www.phantomjs.org/.
PhantomJS it's a CLI tool that runs a real, fully-fledged Browser without the Chrome.