MongoDB: database name must be a string

Issue type:

[ * ] question [ * ] bug report [ ] feature request [ ] documentation issue

Database system/driver:

[ ] cordova [ * ] mongodb [ ] mssql [ ] mysql / mariadb [ ] oracle [ ] postgres [ ] sqlite [ ] sqljs [ ] react-native

TypeORM version:

[ * ] latest [ ] @next [ ] 0.x.x (or put your version here)

Steps to reproduce or a small repository showing the problem:

Create a default project with command

typeorm init --name test --database mongdb --express
cd test
yarn install
yarn start

You can see the following error :

{ MongoError: database name must be a string
     at Function.MongoError.create (/app/node_modules/mongodb-core/lib/error.js:31:11)
     at validateDatabaseName (/app/node_modules/mongodb/lib/db.js:1680:57)
     at new Db (/app/node_modules/mongodb/lib/db.js:156:3)
     at Db.db (/app/node_modules/mongodb/lib/db.js:1208:12)
     at MongoQueryRunner.getCollection (/app/src/driver/mongodb/MongoQueryRunner.ts:803:40)
     at MongoQueryRunner.<anonymous> (/app/src/driver/mongodb/MongoQueryRunner.ts:272:27)
     at step (/app/node_modules/typeorm/driver/mongodb/MongoQueryRunner.js:32:23)
     at Object.next (/app/node_modules/typeorm/driver/mongodb/MongoQueryRunner.js:13:53)
     at /app/node_modules/typeorm/driver/mongodb/MongoQueryRunner.js:7:71
     at new Promise (<anonymous>)
       name: 'MongoError',
       message: 'database name must be a string',
       driver: true }

My ormconfig.json file :

{
   "type": "mongodb",
   "database": "test",
   "synchronize": true,
   "logging": false,
   "entities": [
      "src/entity/**/*.ts"
   ],
   "migrations": [
      "src/migration/**/*.ts"
   ],
   "subscribers": [
      "src/subscriber/**/*.ts"
   ],
   "cli": {
      "entitiesDir": "src/entity",
      "migrationsDir": "src/migration",
      "subscribersDir": "src/subscriber"
   }
}

[Fusseldieb]

I faced this issue and the problem was that somehow it previously worked without specifying a collection name, but now it needs one.

So…

mongoose.connect(
  "mongodb://localhost",
  {
    useNewUrlParser: true
  }
);

gave this error. But then I specified the collection name admin in this way:

mongoose.connect(
  "mongodb://localhost/admin",
  {
    useNewUrlParser: true
  }
);

and the error vanished.

Thanks documentation

[glorious73]

THIS ANSWER WAS EDITED AS THE PREVIOUS ONE LEAD TO OTHER ERRORS I was able to fix the error by adding the following to mongoose.connect() function:

1. After connecting, pass the following parameter: useMongoClient: true
2. Here is how it would look like:
3. Run again, and it should work.