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@jmreidy
Created May 15, 2014 16:14
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An example of DI with Node and Angular's "DI" system
var context = require('voltron-di');
context
.indexModule("Controllers", "server/controllers", {
dependencies: ["Core", "Services"],
type: "factory"
})
.indexModule("DAOs", "server/daos", {
dependencies: ["Core"],
type: "service"
})
.indexModule("Models", "server/models", {
dependencies: ["Core"],
type: "service"
})
.indexModule("Services", "server/services", {
dependencies: ["Core", "DAOs"],
type: "factory"
})
.indexCore({
additionalModules: {
"env": require("../config")
},
aliases: {
"st": "static",
"body-parser": "bodyParser",
"csurf": "csrf",
"cookie-session": "session",
"knex": "Knex"
}
})
.module("App", ["Core", "Controllers"]);
context.module("Core")
.factory("RouterFactory", function (express) {
return function () { return express.Router(); };
})
.factory("knex", function (Knex, env) {
return Knex.initialize(env.database);
});
context.module("App")
.factory("server", require("./index"));
module.exports = context;
@jmreidy
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jmreidy commented May 15, 2014

voltron-di is on Github, but is not really documented at all or tested right now. It's a thin wrapper of NG's DI system, with some convenience functions thrown in.

indexModule will walk a subtree of files and wire them up to the appropriate ng-di module, camelCasing the names as needed. So server/controllers/admin/userController.js would be made accessible in the Controllers module as adminUserController.

indexCore creates a Core module with Node core's modules, and anything in your dependencies in your package.json. It can also alias module names.

Otherwise, things work the same as ng-di. The nice thing is that none of the required files have to reach out to the context to register themselves or to look anything up - although one could argue that tying constructor argument names to injectable signatures is itself a service lookup.

Note that I never inject lodash/underscore or Bluebird/Q, and just use CJS requires for those. They're never going to be tested since they're pure plumbing, and they'd need to be injected into EVERY file, so there's no point.

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