Asynchronous listen (#17)

* Listen to listening event

* Add tests

* Bump version

Author: fijimunkii

index.js

@@ -32,6 +32,12 @@ const createServer = (server, options) => {
     throw err;
   }
 
+  function listen(proxy, server) {
+    const port = server.address().port;
+    server.close();
+    proxied.listen(port, () => console.log(`PROXY protocol parser listening to port ${port}`));
+  }
+
   // create proxy protocol processing server
   const proxied = require('net').createServer(socket => {
     const buf = [];
@@ -111,11 +117,11 @@ const createServer = (server, options) => {
    });
   }
 
+  // listen to listening event
+  server.on('listening', () => listen(proxied, server));
   // if server is already listening, use that port
   if (server.listening) {
-    const port = server.address().port;
-    server.close();
-    proxied.listen(port, () => console.log(`PROXY protocol parser listening to port ${port}`));
+    listen(proxied, server);
   }
 
   return proxied;

package.json

@@ -1,6 +1,6 @@
 {
   "name": "proxyproto",
-  "version": "1.0.10",
+  "version": "1.1.0",
   "description": "Pre-process PROXY protocol headers from node tcp sockets",
   "main": "index.js",
   "scripts": {

test/index.js

@@ -138,13 +138,32 @@ module.exports = async t => {
   });
 
   t.test('listening port is re-used', async (t) => {
-    const server = http.createServer();
-    server.listen(PORT);
-    const proxied = proxyproto.createServer(server);
-    t.ok(proxied.listening);
-    t.notOk(server.listening);
-    t.same(proxied.address().port, PORT);
-    proxied.close();
+    await new Promise(resolve => {
+      const server = http.createServer();
+      server.listen(PORT, () => {
+        const proxied = proxyproto.createServer(server);
+        t.ok(proxied.listening);
+        t.notOk(server.listening);
+        t.same(proxied.address().port, PORT);
+        proxied.close();
+        resolve();
+      });
+    });
+  });
+
+  t.test('listening event is listened to', async (t) => {
+    await new Promise(resolve => {
+      const server = http.createServer();
+      const proxied = proxyproto.createServer(server);
+      proxied.on('listening', () => {
+        t.ok(proxied.listening);
+        t.notOk(server.listening);
+        t.same(proxied.address().port, PORT);
+        proxied.close();
+        resolve();
+      });
+      server.listen(PORT);
+    });
   });
 
   // first load test has ~.2ms added latency