ITrust's complements for Google's Closure library

Javascript module tools

With Google Closure library, it is possible to divide an application into several modules.

How to build automatically javascript modules ? Using Closure builder, you can build your application into several output files. In order to do this, you have to specify to the closure compiler all files included in each plugins: e.g: Mod1 includes file1, file2, file3 and Mod2 includes file4 and file5, and has a dependency to Mod1.

(closure_builder)
--module Mod1:3 \
--module Mod2:2:Mod1 \
--module_output_path_prefix build/module_ \
--js ./file1.js \
--js ./file2.js \
--js ./file3.js \
--js ./file4.js \
--js ./file5.js \

If your application contains a lot of files, it can be boring to list all of them. Using itrustbuilder, you can write a json file describing your modules as follow:

{
    "MODULES_INFO": {
        "Mod1":[],
        "Mod2":["Mod1"]
    },
    "MODULES_URIS":{
        "Mod1":["mod1.js"],
        "Mod2":["mod2.js"]
    }
}

Then pass it to the itrustbuilder.py:

itrustbuilder.py \
    --root=closure-library/ \
    --root=myproject/ \
    --namespace="mynamespace" \
    --modules_info=myproject/module_info.js

Additionnal parameters can be provided :

• modules_info_root: Root path for all URIs specified in the given file;
• modules_info_deps_key: Key used in the file for the deps part;
• modules_info_uris_key: Key used in the file for the URIs part;
• use_renaming_map: Provides an existing renaming map file for the compilation (see Google Closure Stylesheets)

The builder will automatically create --module flags as defined in your JSON file. You will get 2 files once the compilation successed: mod1.js and mod2.js.

Resolving file dependencies into modules Modules loading is managed by ModuleLoader and ModuleManager.

var moduleManager_ = goog.module.ModuleManager.getInstance();
var moduleLoader_ = new goog.module.ModuleLoader();

moduleManager_.setLoader(moduleLoader_);
moduleManager_.setAllModuleInfo(/*modules infos*/);

moduleManager_.setModuleUris(/*modules uris*/);

Usually, having a file containing all modules informations is more conveniant. For instance, the following module_info.js:

goog.provide("myproject.ModuleInfo");

myproject.ModuleInfo = {
    "MODULES_INFO": {
        "Mod1":[],
        "Mod2":["Mod1"]
    },
    "MODULES_URIS":{
        "Mod1":["mod1/mod1_controller.js", "mod1_init.js"],
        "Mod2":["mod2/mod2_class.js", "mod2_init.js"]
    }
}

Note: We use JSON in this object in order to use this same file for the compiler, as explained in the first part.

In order to "deploy" your modules, you have to specify all files' URIs to the ModuleManager. These file will be loaded, in the order you give, and once all file are loaded, your module is executed. Therefore this chain of dependency is very important ! E.g. your Mod1 module requires mod1_controller.js and mod1_init.js. You have to give these URIs to the setModuleUris method:

goog.require('myproject.ModuleInfo');

...

moduleManager_.setModuleUris(myproject.ModuleInfo["MODULES_URIS"]);

When you load your module, all js file will be retrieved and interpreted. However, when you compile your application, you obtain one file per modules you defined (See How to build automatically javascript modules ? part). You will have to change your module info file to this :

goog.provide("myproject.ModuleInfo");

myproject.ModuleInfo = {
    "MODULES_INFO": {
        "Mod1":[],
        "Mod2":["Mod1"]
    },
    "MODULES_URIS":{
        "Mod1":["mod1.js"],
        "Mod2":["mod2.js"]
    }
}

So if you want to work with a compiled and a development version of your application, instead of using goog.module.ModuleManager and goog.module.ModuleLoader, use itrust.module.ModuleManager and itrust.module.ModuleLoader. With the module info file just above and these two files, both your compiled and development version will work properly, and the file dependencies will be automatically resolved using the goog.require() in your code. The use of these files is transparent for you and functions like the closure's file:

goog.require("itrust.module.ModuleManager");
goog.require("itrust.module.ModuleLoader");
goog.require("myproject.ModuleInfo");

var moduleManager_ = itrust.modules.ModuleManager.getInstance();
var moduleLoader_ = new itrust.modules.ModuleLoader();

moduleManager_.setLoader(moduleLoader_);
moduleManager_.setAllModuleInfo(myproject.ModulesInfo["MODULES_INFO"]);

moduleManager_.setModuleUris(myproject.ModulesInfo["MODULES_URIS"], '../', 'goog/');

The only change is the setModuleUris method: two new optional parameters are available.

• The root input path: TO FINISH
• The root output path: TO FINISH