From 26638b0e4e6605014f76cb73a2e3a0b1e0bb6018 Mon Sep 17 00:00:00 2001
From: David Glasser <glasser@davidglasser.net>
Date: Mon, 19 Jul 2021 14:03:27 -0700
Subject: [PATCH] Refactor to repeat less

---
 packages/apollo-server/src/stoppable.ts | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/packages/apollo-server/src/stoppable.ts b/packages/apollo-server/src/stoppable.ts
index 491d8b85920..7a86b60edfc 100644
--- a/packages/apollo-server/src/stoppable.ts
+++ b/packages/apollo-server/src/stoppable.ts
@@ -26,7 +26,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
-import http from 'http';
+import type http from 'http';
 import https from 'https';
 import type { Socket } from 'net';
 
@@ -35,18 +35,16 @@ export class Stopper {
   private stopped = false;
 
   constructor(private server: http.Server | https.Server) {
-    const onConnection = (socket: Socket) => {
-      this.reqsPerSocket.set(socket, 0);
-      socket.once('close', () => this.reqsPerSocket.delete(socket));
-    };
-
-    if (server instanceof https.Server) {
-      server.on('secureConnection', onConnection);
-    } else {
-      server.on('connection', onConnection);
-    }
+    // Keep a number in reqsPerSocket for each current connection.
+    server.on(
+      server instanceof https.Server ? 'secureConnection' : 'connection',
+      (socket: Socket) => {
+        this.reqsPerSocket.set(socket, 0);
+        socket.once('close', () => this.reqsPerSocket.delete(socket));
+      },
+    );
 
-    // Track how many requests are active on the socket.
+    // Track how many HTTP requests are active on the socket.
     server.on(
       'request',
       (req: http.IncomingMessage, res: http.ServerResponse) => {