electrolyte-assembly-mapper

An Assembly Mapper and Loader for the Electrolyte DI/IoC Container in Node.js.

This npm module can be used to map any dependency loaded via Electrolyte to another dependency, like a stub instead of the real implementation.

Installation

npm install electrolyte-assembly-mapper --save

Use case

Given this example web project structure:

app/
  areas/
    homepage/
      controller.js
  lib/
    content-client/
      index.js
      stub.js
  bootstrap.js
  router.js
index.js
package.json

In app/areas/homepage/controller.js you require the content-client dependency:

module.exports = factory
module.exports['@singleton'] = true
module.exports['@require'] = ['lib/content-client']

function factory (content) {
  return (req, res) => {
    const home = await content.getPage('homepage')
    res.end(`<h1>${home.title}</h1>`)
  }
}

If you're bootstrapping Electrolyte with the electrolyte-assembly-mapper from your entrypoint file (index.js):

// Configure DI/IoC container
const IoC = require('electrolyte')
const loader = require('electrolyte-assembly-mapper')('.ioc-mapper.json')
IoC.use(loader('.', 'app'))
IoC.use(IoC.node_modules())

// Start app
IoC.create('app/bootstrap')
  .then(app => app())

The .ioc-mapper.json will instruct to map the content-client to it's stub:

{
  "lib/content-client": "lib/content-client/stub"
}

In this example, it's best to put .ioc-mapper.json in your .gitignore file, since stubs are only used for development.

If the .ioc-mapper.json file is not found, the loader will only load from the specified directories (in the example . and app), and not map to anything. This way you can leave out the .ioc-mapper.json from your deployment package to production.