Plug-in discovery system

Plug-in Discovery

DevSnicket Plug-in Discovery consists of a JavaScript repository object and a Babel plug-in that when used together can invert dependencies between modules and turn them into discovered plug-ins.

before after

There is currently support for file-based CommonJS modules (i.e. not via packages).

Create repository factory function / package

Install using npm :

npm install @devsnicket/plugin-discovery-create-repository

Or with yarn :

yarn add @devsnicket/plugin-discovery-create-repository

The create repository package contains a factory function. When this function is called and the return repository object is exported a plug-in contract is defined (in this example "someSortOfPlugins").

// someSortOfPlugins.js
module.exports =
	require("@devsnicket/plugin-discovery-create-repository")
	();

This can then be plugged into by objects/functions etc from other files.

// plugin1.js
require("./someSortOfPlugins")
.plugin("plug-in number 1");

The plug-ins can then be iterated and used from other files.

// consoleLogPlugins.js
for (const plugin require("./someSortOfPlugins"))
	console.log(plugin);
// output:
// plug-in number 1

The code above alone won't work as there isn't a module require call to import the 2nd plug-in file from the 3rd file that iterates the plug-ins. The purpose of the repository object is so plug-ins can be identified by the @devsnicket/plugin-discovery-create-repository package as it will automatically add the missing module require calls.

CommonJS Babel plug-in / package

The CommonJS Babel plug-in package discovers DevSnicket plug-in usage and will automatically add module require calls where the package @devsnicket/plugin-discovery-create-repository has been used.

Install using npm :

npm install --save-dev @devsnicket/plugin-discovery-commonjs-babel-plugin

Or with yarn :

yarn add --dev @devsnicket/plugin-discovery-commonjs-babel-plugin

The Babel plug-in will need to be specified in your Babel configuration , WebPack Babel Loader configuration or equivalent.

Example

An example of Plug-in Discovery in use can be found in Eunice . A plug-in repository is defined for its test harnesses ( Harnesses/processorPlugins.js ) so processors can be discovered and included automatically.