Voilà File System Dependency Graph

A library for creating a DI graph from modules on the file system

Common usage, with main.js as follows.
If using a build step, the globs should be written to be correct in the transpiled code

const promise = fsGraph({
  globs: [
    `src/controllers/**/*Controller.{js,ts}`,
    `src/daos/**/*Dao.{js,ts}`,
    `src/services/**/*Service.{js,ts}`
  ],
  deriveKey: func => func.name
});

And with the file system arranged as follows.

root
 └─┬src
   ├─┬controllers
   | └──resourceController.js
   ├─┬daos
   | └──resourceDao.js
   ├─┬services
   | └──resourceService.js
   └──main.js

And with the file contents as follows.

resourceController.js

export default function resourceController(resourceService) {

  return {
    doControllerAction(request, reply) {
      // [... transport logic]
      return resourceService.doServiceAction(request.params).then(reply);
    }
  };
}

fsGraph expects that modules that match the glob patterns export a function as module.exports or default. Each function is passed to the deriveKey option to determine its di key. The function arguments are parsed and should coincide with the other keys in the graph--this does not work with transpiled destructuring.

resourceService.js

modules.exports = function resourceService(resourceDao) {

  return {
    doServiceAction(params) {
      // [... business logic]
      return resourceDao.doDaoAction(params);
    }
  };
}

resourceDao.js

export default function resourceDao(/* someClient */) {

  return {
    doDaoAction(params) {
      // [... dao logic]
      // someClient.send(params);
    }
  };
}

This setup will produce a dependency graph, for use with voila-di, as follows.

import fsGraph from 'voila-fs-di';

const promise = fsGraph({
  globs: [
    `src/controllers/**/*Controller.{js,ts}`,
    `src/daos/**/*Dao.{js,ts}`,
    `src/services/**/*Service.{js,ts}`
  ],
  deriveKey: func => func.name
});

promise.then(console.log);

// { resourceController:
//     { dependencies: [ 'resourceService' ],
//       provider: [Function: resourceController] },
//   resourceDao:
//     { dependencies: [],
//       provider: [Function: resourceDao] },
//   resourceService:
//     { dependencies: [ 'resourceDao' ],
//       provider: [Function: resourceService] } }

And this is what the integration looks like.

import fsGraph from 'voila-fs-di';
import di      from 'voila-di';

const promise = fsGraph({
  globs: [
    `src/controllers/**/*Controller.{js,ts}`,
    `src/daos/**/*Dao.{js,ts}`,
    `src/services/**/*Service.{js,ts}`
  ],
  deriveKey: func => func.name
});

promise
  // Validate here if you'd like
  .then(graph => di(graph).get('resourceController'))
  .then(console.log);

// => { doControllerAction: [Function: doControllerAction] }