From c9366427e811dfd0e615c8988245ccdc284e1d80 Mon Sep 17 00:00:00 2001
From: Pier-Luc Gendreau <Zertz@users.noreply.github.com>
Date: Fri, 20 Nov 2020 23:00:39 -0500
Subject: [PATCH 1/2] Update with-mongodb to be TypeScript-friendly

I slightly modified the approach so TypeScript can correctly infer types without actually having to type anything but the global:

**index.d.ts**
```ts
import { Db, MongoClient } from "mongodb";

declare global {
  namespace NodeJS {
    interface Global {
      mongoCache: {
        conn: {
          client: MongoClient | null;
          db: Db | null;
        }
        promise: Promise<MongoClient> | null;
      };
    }
  }
}
```
---
 examples/with-mongodb/util/mongodb.js | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/examples/with-mongodb/util/mongodb.js b/examples/with-mongodb/util/mongodb.js
index 4f0371eddde6a..461aa39959685 100644
--- a/examples/with-mongodb/util/mongodb.js
+++ b/examples/with-mongodb/util/mongodb.js
@@ -20,26 +20,23 @@ if (!MONGODB_DB) {
  * during API Route usage.
  */
 let cached = global.mongo
-if (!cached) cached = global.mongo = {}
+if (!cached) cached = global.mongo = { conn: null, promise: null }
 
 export async function connectToDatabase() {
   if (cached.conn) return cached.conn
   if (!cached.promise) {
-    const conn = {}
     const opts = {
       useNewUrlParser: true,
       useUnifiedTopology: true,
     }
     cached.promise = MongoClient.connect(MONGODB_URI, opts)
       .then((client) => {
-        conn.client = client
-        return client.db(MONGODB_DB)
-      })
-      .then((db) => {
-        conn.db = db
-        cached.conn = conn
+        return {
+          client,
+          db: client.db(MONGODB_DB),
+        }
       })
   }
-  await cached.promise
+  cached.conn = await cached.promise
   return cached.conn
 }

From 0fcbba53432eb1c7dd3e77f297aad347fabcc5f2 Mon Sep 17 00:00:00 2001
From: Pier-Luc Gendreau <Zertz@users.noreply.github.com>
Date: Sat, 21 Nov 2020 13:40:31 -0500
Subject: [PATCH 2/2] lint

---
 examples/with-mongodb/util/mongodb.js | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/examples/with-mongodb/util/mongodb.js b/examples/with-mongodb/util/mongodb.js
index 461aa39959685..59b7c16db2161 100644
--- a/examples/with-mongodb/util/mongodb.js
+++ b/examples/with-mongodb/util/mongodb.js
@@ -29,13 +29,13 @@ export async function connectToDatabase() {
       useNewUrlParser: true,
       useUnifiedTopology: true,
     }
-    cached.promise = MongoClient.connect(MONGODB_URI, opts)
-      .then((client) => {
-        return {
-          client,
-          db: client.db(MONGODB_DB),
-        }
-      })
+
+    cached.promise = MongoClient.connect(MONGODB_URI, opts).then((client) => {
+      return {
+        client,
+        db: client.db(MONGODB_DB),
+      }
+    })
   }
   cached.conn = await cached.promise
   return cached.conn