From 80cba3f3f4483df1285a3675910b7db7271daa55 Mon Sep 17 00:00:00 2001
From: Valeri Karpov <val@karpov.io>
Date: Fri, 20 Sep 2019 15:00:25 -0700
Subject: [PATCH] fix(mongoose): support `mongoose.set('autoIndex', false)`

Fix #8158
---
 lib/index.js |  1 +
 lib/model.js |  5 ++---
 lib/utils.js | 16 ++++++++++++++++
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index c76914492c7..ad89dffc536 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -158,6 +158,7 @@ Mongoose.prototype.driver = require('./driver');
  * - 'strict': true by default, may be `false`, `true`, or `'throw'`. Sets the default strict mode for schemas.
  * - 'selectPopulatedPaths': true by default. Set to false to opt out of Mongoose adding all fields that you `populate()` to your `select()`. The schema-level option `selectPopulatedPaths` overwrites this one.
  * - 'maxTimeMS': If set, attaches [maxTimeMS](https://docs.mongodb.com/manual/reference/operator/meta/maxTimeMS/) to every query
+ * - 'autoIndex': true by default. Set to false to disable automatic index creation for all models associated with this Mongoose instance.
  *
  * @param {String} key
  * @param {String|Function|Boolean} value
diff --git a/lib/model.js b/lib/model.js
index ca41fc0e99b..238b3d73225 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -1184,9 +1184,8 @@ Model.init = function init(callback) {
   }
 
   const Promise = PromiseProvider.get();
-  const autoIndex = this.schema.options.autoIndex == null ?
-    this.db.config.autoIndex :
-    this.schema.options.autoIndex;
+  const autoIndex = utils.getOption('autoIndex',
+    this.schema.options, this.db.config, this.db.base.options);
   const autoCreate = this.schema.options.autoCreate == null ?
     this.db.config.autoCreate :
     this.schema.options.autoCreate;
diff --git a/lib/utils.js b/lib/utils.js
index 7a34b4376fc..846b68ee0ac 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -1072,6 +1072,22 @@ exports.each = function(arr, fn) {
   }
 };
 
+/*!
+ * ignore
+ */
+
+exports.getOption = function(name) {
+  const sources = Array.prototype.slice.call(arguments, 1);
+
+  for (const source of sources) {
+    if (source[name] != null) {
+      return source[name];
+    }
+  }
+
+  return null;
+};
+
 /*!
  * ignore
  */