useNewUrlParser, useUnifiedTopology, useFindAndModify, and useCreateIndex are no longer supported options. Mongoose 6 always behaves as if useNewUrlParser, useUnifiedTopology, and useCreateIndex are true, and useFindAndModify is false. Please remove these options from your code.
[auth] MongoParseError: option usecreateindex is not supported
[auth] at parseOptions (/app/node_modules/mongodb/src/connection_string.ts:358:11)
[auth] at new MongoClient (/app/node_modules/mongodb/src/mongo_client.ts:327:34)
[auth] at /app/node_modules/mongoose/lib/index.js:332:10
[auth] at /app/node_modules/mongoose/lib/helpers/promiseOrCallback.js:32:5
[auth] at new Promise (<anonymous>)
[auth] at promiseOrCallback (/app/node_modules/mongoose/lib/helpers/promiseOrCallback.js:31:10)
[auth] at Mongoose._promiseOrCallback (/app/node_modules/mongoose/lib/index.js:1153:10)
[auth] Server running on port 3000