fix setupDatabase

Author: nbbeeken

.evergreen/run-mongodb-aws-ecs-test.sh

@@ -13,6 +13,3 @@ source ./.evergreen/prepare-shell.sh # should not run git clone
 
 # load node.js
 source $DRIVERS_TOOLS/.evergreen/init-node-and-npm-env.sh
-
-# run the tests
-npm install aws4

.evergreen/setup-mongodb-aws-auth-tests.sh

@@ -23,8 +23,6 @@ cd $DRIVERS_TOOLS/.evergreen/auth_aws
 
 cd $BEFORE
 
-npm install --no-save aws4
-
 if [ $MONGODB_AWS_SDK = 'false' ]; then rm -rf ./node_modules/@aws-sdk/credential-providers; fi
 
 # revert to show test output

test/integration/node-specific/examples/change_streams.test.js

@@ -2,6 +2,7 @@
 'use strict';
 
 const { setTimeout } = require('timers');
+const setupDatabase = require('../../shared').setupDatabase;
 const expect = require('chai').expect;
 
 // TODO: NODE-3819: Unskip flaky MacOS/Windows tests.
@@ -10,9 +11,13 @@ maybeDescribe('examples(change-stream):', function () {
   let client;
   let db;
 
+  before(async function () {
+    await setupDatabase(this.configuration);
+  });
+
   beforeEach(async function () {
     client = await this.configuration.newClient().connect();
-    db = client.db('change_stream_examples');
+    db = client.db(this.configuration.db);
 
     // ensure database exists, we need this for 3.6
     await db.collection('inventory').insertOne({});

test/integration/shared.js

@@ -90,32 +90,21 @@ function ignoreNsNotFound(err) {
   if (!err.message.match(/ns not found/)) throw err;
 }
 
-function setupDatabase(configuration, dbsToClean) {
+async function setupDatabase(configuration, dbsToClean) {
   dbsToClean = Array.isArray(dbsToClean) ? dbsToClean : [];
-  var configDbName = configuration.db;
-  var client = configuration.newClient(configuration.writeConcernMax(), {
-    maxPoolSize: 1
-  });
+  const configDbName = configuration.db;
 
   dbsToClean.push(configDbName);
 
-  return client
-    .connect()
-    .then(() =>
-      dbsToClean.reduce(
-        (result, dbName) =>
-          result
-            .then(() =>
-              client.db(dbName).command({ dropAllUsersFromDatabase: 1, writeConcern: { w: 1 } })
-            )
-            .then(() => client.db(dbName).dropDatabase({ writeConcern: { w: 1 } })),
-        Promise.resolve()
-      )
-    )
-    .then(
-      () => client.close(),
-      err => client.close(() => Promise.reject(err))
-    );
+  const client = configuration.newClient(configuration.writeConcernMax());
+  try {
+    for (const dbName of dbsToClean) {
+      await client.db(dbName).command({ dropAllUsersFromDatabase: 1, writeConcern: { w: 1 } });
+      await client.db(dbName).dropDatabase({ writeConcern: { w: 1 } });
+    }
+  } finally {
+    await client.close();
+  }
 }
 
 /**