feat: add support for setting mongoose connection options

docs/getting-started/installation.mdx

@@ -105,6 +105,10 @@ This is a fully qualified MongoDB connection string that points to your Mongo da
 
 In contrast to running Mongo locally, a popular option is to sign up for a free [MongoDB Atlas account](https://www.mongodb.com/cloud/atlas), which is a fully hosted and cloud-based installation of Mongo that you don't need to ever worry about.
 
+##### `mongoOptions`
+
+An optional object to customize connection options. Payload will connect to your MongoDB database using default options which you can override and extend to include all the [options](https://mongoosejs.com/docs/connections.html#options) available to mongoose.
+
 ##### `express`
 
 This is your Express app as shown above. Payload will tie into your existing `app` and scope all of its functionalities to sub-routers. By default, Payload will add an `/admin` router and an `/api` router, but you can customize these paths.

src/config/types.ts

@@ -4,6 +4,7 @@ import { Transporter } from 'nodemailer';
 import { Configuration } from 'webpack';
 import SMTPConnection from 'nodemailer/lib/smtp-connection';
 import GraphQL from 'graphql';
+import { ConnectionOptions } from 'mongoose';
 import { Payload } from '..';
 import { AfterErrorHook, PayloadCollectionConfig, CollectionConfig } from '../collections/config/types';
 import { PayloadGlobalConfig, GlobalConfig } from '../globals/config/types';
@@ -48,6 +49,7 @@ export function hasTransportOptions(emailConfig: EmailOptions): emailConfig is E
 export type InitOptions = {
   express?: Express;
   mongoURL: string;
+  mongoOptions?: ConnectionOptions;
   secret: string;
   license?: string;
   email?: EmailOptions;

src/index.ts

@@ -1,6 +1,5 @@
 import express, { Express, Router } from 'express';
 import crypto from 'crypto';
-import { TestAccount } from 'nodemailer';
 import {
   Config,
   EmailOptions,
@@ -32,7 +31,7 @@ import performFieldOperations from './fields/performFieldOperations';
 import localOperations from './collections/operations/local';
 import localGlobalOperations from './globals/operations/local';
 import { encrypt, decrypt } from './auth/crypto';
-import { MockEmailHandler, BuildEmailResult, Message } from './email/types';
+import { BuildEmailResult, Message } from './email/types';
 import { PayloadRequest } from './express/types';
 import sendEmail from './email/sendEmail';
 
@@ -143,7 +142,7 @@ export class Payload {
     initGlobals(this);
 
     // Connect to database
-    connectMongoose(this.mongoURL);
+    connectMongoose(this.mongoURL, options.mongoOptions);
 
     // If not initializing locally, set up HTTP routing
     if (!this.local) {

src/mongoose/connect.ts

@@ -1,12 +1,19 @@
 /* eslint-disable no-console */
-import mongoose from 'mongoose';
+import mongoose, { ConnectionOptions } from 'mongoose';
 import Logger from '../utilities/logger';
 
 const logger = Logger();
 
-const connectMongoose = async (url: string): Promise<void> => {
+const connectMongoose = async (url: string, options: ConnectionOptions): Promise<void> => {
   let urlToConnect = url;
   let successfulConnectionMessage = 'Connected to Mongo server successfully!';
+  const connectionOptions = {
+    ...options,
+    useNewUrlParser: true,
+    useUnifiedTopology: true,
+    useCreateIndex: true,
+    autoIndex: false,
+  };
 
   if (process.env.NODE_ENV === 'test') {
     // eslint-disable-next-line global-require
@@ -22,12 +29,7 @@ const connectMongoose = async (url: string): Promise<void> => {
   }
 
   try {
-    await mongoose.connect(urlToConnect, {
-      useNewUrlParser: true,
-      useUnifiedTopology: true,
-      useCreateIndex: true,
-      autoIndex: false,
-    });
+    await mongoose.connect(urlToConnect, connectionOptions);
     logger.info(successfulConnectionMessage);
   } catch (err) {
     logger.error('Error: cannot connect to MongoDB. Details: ', err);