plugin: Plugin modules now export a single top level identifier

Makes typing much easier. Addresse's Will's last comment.

src/node/plugin.ts

@@ -189,11 +189,16 @@ export class PluginAPI {
       )
     }
 
+    const pluginModule = require(dir)
+    if (!pluginModule.plugin) {
+      throw new Error("plugin module does not export a plugin")
+    }
+
     const p = {
       name: packageJSON.name,
       version: packageJSON.version,
       modulePath: dir,
-      ...require(dir),
+      ...pluginModule.plugin,
     } as Plugin
 
     if (!p.displayName) {

test/test-plugin/src/index.ts

@@ -2,24 +2,25 @@ import * as express from "express"
 import * as fspath from "path"
 import * as pluginapi from "../../../typings/pluginapi"
 
-export const displayName = "Test Plugin"
-export const routerPath = "/test-plugin"
-export const homepageURL = "https://example.com"
-export const description = "Plugin used in code-server tests."
+export const plugin: pluginapi.Plugin = {
+  displayName: "Test Plugin",
+  routerPath: "/test-plugin",
+  homepageURL: "https://example.com",
+  description: "Plugin used in code-server tests.",
 
-export function init(config: pluginapi.PluginConfig) {
+  init: (config) => {
     config.logger.debug("test-plugin loaded!")
-}
+  },
 
-export function router(): express.Router {
+  router: () => {
     const r = express.Router()
     r.get("/goland/icon.svg", (req, res) => {
       res.sendFile(fspath.resolve(__dirname, "../public/icon.svg"))
     })
     return r
-}
+  },
 
-export function applications(): pluginapi.Application[] {
+  applications: () => {
     return [
       {
         name: "Test App",
@@ -31,4 +32,5 @@ export function applications(): pluginapi.Application[] {
         homepageURL: "https://example.com",
       },
     ]
+  },
 }

typings/pluginapi.d.ts

@@ -16,7 +16,8 @@ import * as express from "express"
 /**
  * Plugins
  *
- * Plugins are just node modules.
+ * Plugins are just node modules that contain a top level export "plugin" that implements
+ * the Plugin interface.
  *
  * 1. code-server uses $CS_PLUGIN to find plugins.
  *
@@ -78,7 +79,7 @@ import * as express from "express"
  */
 
 /**
- * Your plugin module must implement this interface.
+ * Your plugin module must have a top level export "plugin" that implements this interface.
  *
  * The plugin's router will be mounted at <code-sever-root>/<plugin-path>
  */