feat(plugin-koa): Add complete types

Author: bengourley

packages/plugin-koa/package-lock.json

@@ -29,6 +29,7 @@
     "@bugsnag/js": "*"
   },
   "devDependencies": {
+    "@types/koa": "^2.11.3",
     "jasmine": "^3.1.0",
     "nyc": "^12.0.2"
   },

packages/plugin-koa/package.json

@@ -1,3 +1,23 @@
-import { Plugin } from '@bugsnag/node'
+import { Client, Plugin } from '@bugsnag/core'
+import * as Koa from 'koa'
 declare const bugsnagPluginKoa: Plugin
 export default bugsnagPluginKoa
+
+interface BugsnagPluginKoaResult {
+  errorHandler: (err: Error, ctx: Koa.Context) => void
+  requestHandler: Koa.Middleware
+}
+
+// add a new call signature for the getPlugin() method that types the plugin result
+declare module '@bugsnag/core' {
+  interface Client {
+    getPlugin(id: 'koa'): BugsnagPluginKoaResult | undefined
+  }
+}
+
+// define ctx.bugsnag for koa middleware by declaration merging
+declare module 'koa' {
+  interface BaseContext {
+    bugsnag?: Client
+  }
+}

packages/plugin-koa/types/bugsnag-koa.d.ts

@@ -69,5 +69,6 @@
     "packages/plugin-react",
     "packages/plugin-vue",
     "packages/plugin-express",
+    "packages/plugin-koa",
   ]
 }