Using code in both Actionscript3 and Javascript - javascript

Here's an interesting architectural query. I have a piece of code that needs to run on the server (under Node.js) and on the client (in a Flash 10 app written with Actionscript 3). The code is mostly fairly intricate object manipulation, it doesn't make any API calls, and works fine in both contexts.
So far the project is just a demo, so I've been happy to copy and paste the code into both places. But it might be quite interesting to move forward with this.
So how would you do it?
I assume there is no easy way to get the Flash SDK (has to build without an IDE) to read and do something useful with a .js file.
My only thought is that I could write a code-generator that takes the .js file and places it in an ActionScript wrapper.
Are there any obvious approaches that I've missed?
Just to pre-empt an obvious answer, I know about cross-platform languages like Haxe.

A possible way is using include in your wrapper Actionscript code. Just a quick and very simple test:
package {
import flash.display.Sprite;
import flash.text.TextField;
public class Main extends Sprite {
private var _alertTxt:TextField;
include "some.js"
public function Main() {
_alertTxt = new TextField();
_alertTxt.multiline = true;
_alertTxt.height = 400;
_alertTxt.width = 400;
addChild(_alertTxt);
run();
}
public function alert(msg) {
_alertTxt.text += msg + "\n";
}
}
}
some.js
function run() {
alert("run");
var obj = {
a : 'hello',
b : 4.5,
c : false
};
loop(obj);
}
function loop(obj) {
for (var field in obj) {
alert(obj[field]);
}
}
To compile from command-line (you might want to add other options):
mxmlc -strict=false Main.as
If you don't set strict to false, it won't compile because of the lack of type declarations.

Related

How / where does one define AudioWorkletProcessor

I have just started playing with the Web Audio API. I have been pouring over the API docs and see several examples. My issue is probably trivial and I am probably missing something fundamental.
I have the worker javascript file below. It came from an example whoes URL I have misplaced. I am using PyCharm as my IDE, if that matters, and it flags "AudioWorkletProcessor" as undefined. I have looked at a lot of pages at this point and I do not see any import or require statements that might define this interface.
I have just tried running the code in Firefox and Chrome and both throw exceptions on the undefined AudioWorkletProcessor line.
Should this be a "builtin"? Is it part of a library/module that I just haven't seen referenced yet?
class AudioRecorder extends AudioWorkletProcessor {
static get parameterDescriptors() {
return [
{
name: 'isRecording',
defaultValue: 0,
minValue: 0,
maxValue: 1,
},
]
}
process(inputs, outputs, parameters) {
const buffer = []
const channel = 0
for (let t = 0; t < inputs[0][channel].length; t += 1) {
if (parameters.isRecording[0] === 1) { // <2>
buffer.push(inputs[0][channel][t])
}
}
if (buffer.length >= 1) {
this.port.postMessage({buffer})
}
return true
}
}
registerProcessor('audio-recorder', AudioRecorder)
The AudioWorkletProcessor base class and the registerProcessor() function are both available as globals in the AudioWorkletGlobalScope.
It's not possible to evaluate that code in the console. You need to load your JavaScript file like that:
audioContext.audioWorklet.addModule('path/to/your/file.js');
I guess your IDE is just not aware of the fact that you are editing something that is meant to be evaluated in that scope.

Unity - communicating with clientside Javascript and ajax. How to pass data back to the webpage from unity?

What I am really asking is this; if there are dependencies which are impossible to compile into the unity build, is there a way of still calling them from within the unity and simply using the scripts loaded into the browser from the website and communicating with them?
Relevant documentation does not address this deeply:
https://docs.unity3d.com/Manual/webgl-interactingwithbrowserscripting.html
I am creating a website wrapper for a unity application. The buttons for the experience are located within the website, as the buttons affect the rest of the site, not just the unity application.
When certain content is loaded in the unity game play however, the app needs to be able to affect the website. Is there a way to pass the data back to the website in a creative way? Currently, I am including all my javascript code for the website in the unity compile, and it is erroring out on:
gameInstance = UnityLoader.instantiate("gameContainer", "/Build/DomumProto16_Web.json", {
onProgress: UnityProgress
});
Sending data to the gameplay from the website:
gameInstance.SendMessage('Manager','Filter', JSON.stringify(filterActive));
Need to call this function from the unity gameplay. However, ajax.ajax_url is undefined due to it being localized using wp_localize_script() on the backend.
function showStudentWork(studentIndex){
//make sure to remove all the
var x = document.getElementById("studentWork");
var studentID = studentWork[studentIndex];
console.log(studentID);
$.ajax({
url: ajax.ajax_url,
type: "POST",
data: {
action: 'getStudentPost',
currentStudent: studentID
},
success: function (data) {
x.innerHTML = "";
x.innerHTML = data;
x.style.display = "grid";
},
error: function (error) {
console.log(`Error ${error}`);
}
});
return false;
}
What I am really asking is this; if there are dependencies which are impossible to compile into the unity build, is there a way of still calling them from within the unity and simply using the scripts loaded into the browser from the website and communicating with them?
Here are two methods. One is, in my opinion, easier, but it is deprecated and you should ~not~ use it. Options two is the 'corrrect' way, but it is kinda ugly imo.
Option 1: Application.ExternalCall
Documentation
This option allows you to call browser javascript directly, but Unity has deprecated support for it and is probably a bad idea for anything long term.
In a given browser with a Unity web player working, consider the following:
In browser source, define a javascript function
<other html>
<script>
function foo(msg) {
alert(msg);
}
</script>
In Unity, whenever it is nessecary:
Application.ExternalCall( "foo", "The game says hello!" );
This allows Javascript to be called from Unity.
There is similar functionality for communication in the opposite direction.
Option 2: jslibs
Documentation
This is the unity-endorsed way of doing things. It involved packaging javascript libraries into your games.
First, create a javascript file that will be packaged with your game. Here is an example file:
// Unity syntactic sugar
mergeInto(LibraryManager.library, {
// Declare all your functions that can be called from c# here
alert_user: function (msg) {
window.alert(msg);
},
other_func: function () {
// does something else
// etc.
// put as many functions as you'd like in here
}
}
Place that file, with extension .jslib in your Plugins folder on your project.
Then, in your c# files, you need to:
// Declare a monobehavior, whatever
using UnityEngine;
using System.Runtime.InteropServices;
public class NewBehaviourScript : MonoBehaviour {
// IMPORTANT
// You have to declare the javascript functions you'll be calling
// as private external function in your c# file. Additionally,
// They need a special function decorator [DllImport("__Internal")]
// Example:
[DllImport("__Internal")]
private static extern void alert_user(string msg);
// With that unpleasantness over with, you can now call the function
void Start() {
alert_user("Hello, I am a bad person and I deserve to write c#");
}
}
Et viola. You can call other javascript from your c# javascript, and interact with the dom, but I will leave all those decisions up to you.
The other direction
In both cases, communication in the opposite direction (browser saying something to Unity) is the same format.
In javascript, create a UnityInstance (the way of this is a little two long-winded to put into this answer, check either docs). Then, just .sendMessage.
e.g.:
c#
...
void DoSomething (string msg) {
// this is a c# function that does something in the game
// use your imagination
}
...
javascript:
let game = UnityLoader // Actually load the game here
game.SendMessage('TheNameOfMyGameObject', 'DoSomething', 'This is my message');
If I understand it can be done using WWW call function
This is not a proper code okay . This will be just an idea for you.
Send a variable to the PHP function like this
string url = "" // add your URL here;
WWWForm form = new WWWForm ();
form.AddField("YourFunctionName", "SampleFunction");
WWW www = new WWW(url, form);
yield return www;
Now in your PHP do it something like this
function YourFunctionName()
{
// your function code here
}
and now on
$YourFunctionName = $_POST["functionName"];
switch ($functionName){
case "SampleFunction":
SampleFunction();
break;
}
So the idea here is still you will need a PHP and from that PHP call your ajax :)

Sharing JS files across application

We're developing a mobile application and we're trying to figure out the best approach to share javascript functions across the application.
At the moment we have individual files that simply have:
var LIB = {
URL: "http://localhost/service",
connect: function() {
// connect to server
$.ajax({ url: this.URL }); // etc etc
// call a private function?
this._somethingElse();
},
_somethingElse: function() {
// do something else
}
};
Then we simply call things like:
LIB.connect(); or LIB.disconnect();
across any file.
This also gives us access to LIB.URL as well.
My question is whether this approach is the best?
I've seen people use the following approach as well, but to what benefit?
var LIB = function () {
this.URL = "http://localhost/service";
this.connect = function () {
var myself = this;
// connect to server
$.ajax({ url: this.URL }); // etc etc
// call a private function?
myself._somethingElse(); // best way to invoke a private function?
};
this._somethingElse = function () {
// do something else
};
};
This requires the following:
var lib = new LIB();
lib.connect();
EDIT:
I've also seen the following:
window.lib = (function () {
function Library () {
}
var lib = {
connect: function () {
// connect to server
}
};
return lib;
}());
I'm slightly confused with all these options.
It just depends on which you like better. I (on a personal level) prefer the former, but to each his own. The latter does have the disadvantage of requiring to either remember to declare the new before using it, or having to keep track of a already created one.
Additionally, on a technical level the first one should get slightly (as in, barely noticeable) performance, as you don't have to compute a new function.
Edit Yes, the first way is definitely the fastest.
I highly recommend going with a module system. Until ES6 comes along (http://wiki.ecmascript.org/doku.php?id=harmony:modules), you will have to use a 3rd party library in order to do this.
Each object/class/util/etc is a module.
A module exports a public api, whereas consuming modules import other modules by declaring their dependencies.
Two "standards" that exist: AMD and CommonJS. In the browser, a library like RequireJS, which uses the AMD standard, is very popular. I recommend checking out their site first: http://requirejs.org/ and see their examples.
The main advantage here is that you only expose the public api, which allows you to create a sandbox of your functionality. It's also more explicit as it's really easy to see what your module depends on, instead of relying on global objects.
There are several different approaches to structuring JavaScript code for re-usability. You can research these and decide which is best. Me personally, I have used the second approach that you've outlined. However, I separate my code into sections and actually adhere to an MVVM structure. So for instance, I have a name space called models and view models. Each of my js files begins with:
window.[APP NAME].Models.[CLASS/MODULE NAME] or window.[APP NAME].Models.[CLASS/MODULE NAME]
So, let's say I have a namespace called mynamespace and I have a module/class called myclass. My js file would begin with:
window.MYNAMESPACE = window.MYNAMESPACE || {};
window.MYNAMESPACE.ViewModels = window.MYNAMESPACE.ViewModels || {};
window.MYNAMESPACE.ViewModels.MyClass = function () {
// a public function
this.func1 = function () {
};
// a private function
function func2() {
}
};
I would then consume that class by calling:
var myClassModel = new window.MYNAMESPACE.ViewModels.MyClass();
myClassModel.func1();
This gives you some nice encapsulation of your code. Some of the other patterns you can research/google are: Prototype Pattern, Module Pattern, Revealing Module Pattern, and the Revealing Prototype Pattern.
I hope that helps but if you have any questions on what I've just said, feel free to comment on this post.

Haxe for javascript without global namespace pollution?

This question only applies to Haxe version < 2.10
I've known about haxe for a while, but never really played with it until yesterday. Being curious, I decided to port showdown.js, a javascript port of markdown.pl, to haxe. This was pretty straightforward, and the javascript it generates seems to run fine (edit: If you want to see it in action, check it out here).
However, I noticed that the generated code dumps a ton of stuff in the global namespace... and what's worse, it does it by assigning values to undeclared identifiers without using the var keyword, so they're global even if you wrap the whole thing with a closure.
For example...
if(typeof js=='undefined') js = {}
...
Hash = function(p) { if( p === $_ ) return; {
...
EReg = function(r,opt) { if( r === $_ ) return; {
...
I managed to clean most of that up with sed, but I'm also bothered by stuff like this:
{
String.prototype.__class__ = String;
String.__name__ = ["String"];
Array.prototype.__class__ = Array;
Array.__name__ = ["Array"];
Int = { __name__ : ["Int"]}
Dynamic = { __name__ : ["Dynamic"]}
Float = Number;
Float.__name__ = ["Float"];
Bool = { __ename__ : ["Bool"]}
Class = { __name__ : ["Class"]}
Enum = { }
Void = { __ename__ : ["Void"]}
}
{
Math.__name__ = ["Math"];
Math.NaN = Number["NaN"];
Math.NEGATIVE_INFINITY = Number["NEGATIVE_INFINITY"];
Math.POSITIVE_INFINITY = Number["POSITIVE_INFINITY"];
Math.isFinite = function(i) {
return isFinite(i);
}
Math.isNaN = function(i) {
return isNaN(i);
}
}
This is some pretty unsavory javascript.
Questions
Is there a fork or clone of haxe somewhere that doesn't pollute globals? Is it worth it to modify the haxe source to get what I want, or has someone already solved this? Googling hasn't turned up much. I'm open to any suggestions. Meanwhile, I'm dying to see what kind of PHP code this thing's going to produce... :D
Answers?
Here are some of the ideas I've tried:
postprocessing
Here's my humble build script; it does a pretty good job of stripping stuff out, but it doesn't catch everything. I'm hesitant to remove the modifications to the built-in constructor prototypes; I'm sure that would break things. Fixing everything might be a bit of a task, and I don't want to start on it if someone's already done the work...
haxe -cp ~/Projects/wmd-new -main Markdown -js markdown.js
echo "this.Markdown=(function(){ var \$closure, Float;" > markdown.clean.js;
sed "s/^if(typeof js=='undefined') js = {}$/if(typeof js=='undefined') var js = {};/g ;
s/^\([ \x09]*\)\([\$_a-zA-Z0-9]* = \({\|function\)\)/\1var \2/g ;
/^[ \x09]*\(else \)\?null;$/d ;
" markdown.js >> markdown.clean.js
echo "return Markdown}());" >> markdown.clean.js;
java -jar closure/compiler.jar --js markdown.clean.js \
--compilation_level SIMPLE_OPTIMIZATIONS \
> markdown.cc.js
--js-namespace switch saves the day
Thanks to Dean Burge for pointing out the namespace switch. This pretty much solved my problem, with a minor bit of help. Here's my current build script. I think this catches all the global variables...
NS=N\$
haxe -cp ~/Projects/wmd-new -main Markdown --js-namespace $NS -js markdown.js
# export our function and declare some vars
echo "this.markdown=(function(){var \$_,\$Main,\$closure,\$estr,js,"$NS"" > markdown.clean.js;
# strip silly lines containing "null;" or "else null;"
sed "/^[ \x09]*\(else \)\?null;$/d ;" markdown.js >> markdown.clean.js
# finish the closure
echo "return "$NS".Markdown.makeHtml}());" >> markdown.clean.js;
I use the namespace switch on the compiler to clean those global root types up.
Haxe is not meant to be used for writing an isolated reusable component in a javascript web application. This is evidenced by the fact that the compiler emits standard library for every goddamn compilation. Most optimal use of javascript target is to write an application entirely in haxe and call external stuff using untyped blocks hoping it won't break anything. You should treat haxe output like a flash clip, oblivious to the environment it runs in, assumes it is the only thing running.
Or you might try wrapping the code with a with() block.
there's a namespaced (experimental) haxe compiler here http://github.com/webr3/haxe
The JSTM JavaScript generator macro optimizes haxe output in a number of ways:
the javascript output is split into seperate files per type
these files are optimized
a loader script loads the required types asynchronously
only one global variable is used: jstm
only code that is actually required to run your app is downloaded
new types can be loaded at runtime which makes possible highly scalable apps
check out http://code.google.com/p/jstm/ for more info.

Testing private functions in javascript

I'm using the module pattern in Javascript to separate my public interface from the private implementation. To simplify what I'm doing, my code generates a chart. The chart consists of multiple parts (axises, labels, plot, legend, etc.) My code looks like:
var Graph = function() {
var private_data;
function draw_legend() { ... }
function draw_plot() { ... }
function helper_func() { ... }
...
return {
add_data: function(data) {
private_data = data;
},
draw: function() {
draw_legend()
draw_plot()
}
}
}
Some people advocate only testing the public interface of your classes, which makes sense, but I'd really like to get in some tests to test each of the components separately. If I screw up my draw_legend() function, I'd like that test to fail, not a test for the public draw() function. Am I on the wrong track here?
I could separate each of the components in different classes, for example make a Legend class. But it seems silly to create a class for what's sometimes just 5-10 lines of code, and it would be uglier because I'd need to pass in a bunch of private state. And I wouldn't be able to test my helper functions. Should I do this anyway? Should I suck it up and only test the public draw()? Or is there some other solution?
There is no way to access inner functions (private) from an outer scope. If you want to test inner functions you might consider adding a public method for testing purposes only. If you are using some sort of a build environment, for example ant, you may pre-process the javascript file for production and remove those test functions.
Actually Javascript is an Object oriented language. It's just not a statitcally typed one.
My solution is just a little bit of hack. QUnit example:
At the top of Qunit test html I have declared:
var TEST_AVAILABLE = true;
In the testable class I have a fragment like this:
if(TEST_AVAILABLE){
this.test={
hasDraft:hasDraft,
isInterpIdIn:isInterpIdIn,
// other private methods
};
}
In the QUnit you could verify
test( "hello booth", function() {
var b = new Booth();
ok(b);
ok(b.test);
ok(!b.test.hasDraft());
});
I have a similar problem. The solution I came up with is not something I like but it does the job and there's not a better solution I can find.
function Graph()
{
this.Test = function _Test(expressionStr) { return eval(expressionStr); }
var private_data;
function draw_legend() { ... }
function draw_plot() { ... }
function helper_func() { ... }
...
}
To test:
var g = new Graph();
g.Test("helper_func()") == something;
g.Test("private_data") == something2
There is an easy way actually. You can use ajax to load the script and inject a function that exposes the private functions. I have an example here that uses qUnit and jQuery. But I'm sure the same can be easily accomplished using pure Javascript.
In an object oriented language, you would typically unit test the protected methods by having the test class inherit from the class it's testing.
Of course, Javascript is not really an object oriented language, and this pattern does not allow for inheritance.
I think you either need to make your methods public, or give up on unit testing them.
There is the only one right option: Different Builds for Testing and Production
1) mark development only parts
/* test-code */
api._foo = foo
/* end-test-code */
2) strip them later... ;)
grunt.registerTask("deploy",
[
"concat",
"strip-code",
...
#philwalton has written beautiful articles:
HOW: https://philipwalton.com/articles/how-to-unit-test-private-functions-in-javascript/
WHY: https://philipwalton.com/articles/why-i-test-private-functions-in-javascript/

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