Plugins

A plugin adds a feature in two halves: Go services, and a JavaScript package whose functions call them. The app uses the Go half with mygo.Use and imports the JavaScript half from npm.

Official plugins

The updater plugin, github.com/egoist/mygo/plugins/updater, is all Go: it gives the app an update window in the manner of Sparkle, which checks for updates in the background and offers to install them. See the update window.

import (
	"github.com/egoist/mygo"
	"github.com/egoist/mygo/plugins/fetch"
	"github.com/egoist/mygo/plugins/websocket"
)

func main() {
	mygo.Use(fetch.Plugin, websocket.Plugin)
	// ...
}

bun add @mygo-plugins/fetch @mygo-plugins/websocket

import { fetch } from "@mygo-plugins/fetch";
import { WebSocket } from "@mygo-plugins/websocket";

const res = await fetch("https://api.example.com/me", {
  headers: { authorization: `Bearer ${token}` },
});
const ws = new WebSocket("wss://api.example.com/live", [], {
  headers: { authorization: `Bearer ${token}` },
});

fetch.Plugin and websocket.Plugin use the default options; fetch.New and websocket.New take an http.Client (for proxies, cookies, TLS settings) and an Allow function that decides which requests pages may make. The packages' READMEs, in the repository's plugins directory, list the details, and go doc documents the options.

Using a plugin's JavaScript package without its Go half fails with an error that says to call mygo.Use.

Writing a plugin

The Go half is a mygo.Plugin: a name, a service whose methods pages call, and an optional Setup that runs when the app uses it:

package clock

// Plugin gives pages the time of the Go side.
var Plugin = mygo.Plugin{Name: "clock", Service: service{}}

type service struct{}

func (service) Now() time.Time { return time.Now() }

The service is bound like those of mygo.Bind, with the same rules for its methods (contexts, channels, errors), but as plugin:<name> and outside the generated TypeScript client. Its JavaScript package calls it with call of mygo-runtime, which it lists as a peer dependency, so that it uses the app's copy (and as a development dependency, for its own builds and tests):

import { call } from "mygo-runtime";

export const now = async () => new Date(await call<string>("plugin:clock.Now"));

Only the app's trusted pages may call a plugin, as with every bound method. mygo.Use panics when a name is taken or the service's methods use types that cannot cross to JavaScript, so mistakes show at startup.