add pretty message if port already use(vercel#927)

dex157 · Jan 30, 2017 · 0efd6f9 · 0efd6f9
1 parent 0d2af80
commit 0efd6f9
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Showing 2 changed files with 10 additions and 3 deletions.
diff --git a/bin/next-dev b/bin/next-dev
@@ -61,6 +61,10 @@ srv.start(argv.port)
   }
 })
 .catch((err) => {
-  console.error(err)
+  if (err.code === 'EADDRINUSE') {
+    console.error(`Port ${argv.port} is already in use.\nUse \`npm run dev -- -p <some other port>\`.`)
+  } else {
+    console.error(err)
+  }
   process.exit(1)
 })
diff --git a/server/index.js b/server/index.js
@@ -119,10 +119,13 @@ export default class Server {
     await this.prepare()
     this.http = http.createServer(this.getRequestHandler())
     await new Promise((resolve, reject) => {
-      this.http.listen(port, (err) => {
-        if (err) return reject(err)
+      this.http.on('error', (error) => {
+        reject(error)
+      })
+      this.http.on('listening', () => {
         resolve()
       })
+      this.http.listen(port, () => {})
     })
   }