pluggage

A very slim framework for building pluggable code.

If you want to build an application or a framework that uses plugins for extensibility, you should take a look at pluggage. Pluggage takes care of discovery and lifecycle management of the plugins. Beyond that, pluggage imposes very little on the interaction between plugin and host.

Pluggage is a combination of plugin and package, but it also sounds a lot like luggage

install

With npm do:

npm install --save pluggage

host/load plugins in your code

A plugin host manages discovery and lifecycle of plugins. It can also expose an api to them. To install a plugin simply npm install your-plugin in the host application. This can be an npm package or local code installed as a package (more on that here)

Using exact or prefix in the host(...) options will make pluggage automatically load and initialize packages that were npm installed.

const pluggage = require('pluggage')

async function main() {
    const hostApi = {
        foo: () => {}
    }

    // load all plugins who's package name starts with `generator-``
    const host = pluggage.host({ prefix: 'generator-', hostApi })

    // initialize the plugins
    await host.init()
    await host.shutdown()

    // load the plugins who's package name exactly match the names specified in the array
    const exactHost = pluggage.host({ exact: ['plugin1', 'plugin2'], hostApi })
}

main()

Creating a plugin

A plugin is just a package that exports the pluggage interface (using the pluggage property).

const pluggage = require('pluggage')

module.exports.pluggage = pluggage.plugin({
   init:  async (hostApi) => {},
   shutdown: async () => {}
})

IMPORTANT: Installing the package in a plugin module

Doing npm i pluggage for this scenario is not a good idea. It will cause the host and the plugin to have different instances of what's suppose to be the same class. You're welcome to read more about this kind of problem here.

When developing the pluing module separately (ie not as a local package - discussed here) you should have it as both dev and peer depedency:

{
    "peerDependencies": {
        "pluggage": "1.x"
    },
    "devDependencies": {
        "pluggage": "x.y.z"
    }
}

local packages do not need the devDepenendencies.

This is a little awkward, and maybe there's a better solution... please share it if you have one.

license

MIT © Yaniv Kessler