fix: capture websocket server errors (#131)

* fix: capture websocket server errors

* add tests

Author: lynxtaa

index.js

@@ -88,6 +88,10 @@ function setupWebSocketProxy (fastify, options) {
     oldClose.call(this, done)
   }
 
+  server.on('error', (err) => {
+    fastify.log.error(err)
+  })
+
   server.on('connection', (source, request) => {
     const url = createWebSocketUrl(options, request)
 

test/websocket.js

@@ -52,3 +52,18 @@ test('basic websocket proxy', async (t) => {
     server.close()
   ])
 })
+
+test('captures errors on start', async (t) => {
+  const app = Fastify()
+  await app.listen(0)
+
+  const app2 = Fastify()
+  app2.register(proxy, { upstream: 'http://localhost', websocket: true })
+
+  const appPort = app.server.address().port
+
+  await t.rejects(app2.listen(appPort), /EADDRINUSE/)
+
+  t.tearDown(app.close.bind(app))
+  t.tearDown(app2.close.bind(app2))
+})