Unable to connect to MongoDB through docker-compose network (configured with replicaset)

Bug description

Hi! I think I have an issue that is probably related to this one https://github.com/prisma/prisma/issues/11860. Prisma can’t pull/connect from MongoDB, if it is in the other container in the same docker-compose network. Meaning that Prisma won’t connect when I use connection string

DATABASE_URL="mongodb://mongo:27017/mongo"

instead of

DATABASE_URL="mongodb://localhost:27017/mongo"

even though this connection string would work with other clients (mongosh, MongoDB for VSCode in dev container)

How to reproduce

Steps to reproduce:

1. Spin up docker-compose with:

• a. MongoDB with replica set setup, (e.g. from this docker-compose file https://github.com/prisma/prisma/blob/main/docker/docker-compose.yml)
• b. Node.js container with Prisma and prisma.schema (and optional @prisma/client simple setup)

1. Run ```npx prisma db pull`` in Node.js container, it gives error:

Error: Error in connector: Error querying the database: Server selection timeout: No available servers. Topology: { Type: ReplicaSetNoPrimary, Servers: [ { Address: localhost:27018, Type: Unknown, Error: Cannot assign requested address (os error 99) }, ] }

1. Or start Node.js with @prisma/client, it gives similar error:

PrismaClientInitializationError: Database error. error code: unknown, error message: Server selection timeout: No available servers. Topology: { Type: ReplicaSetNoPrimary, Servers: [ { Address: localhost:27017, Type: Unknown, Error: Cannot assign requested address (os error 99) }, ] }
    at /app/node_modules/@prisma/client/runtime/index.js:36300:21 {
  clientVersion: '3.9.2',
  errorCode: undefined
}

1. Finally, make sure that the connection string is valid if used through the other MongoDB client from the same container. E.g. install mongosh to the interactive Node.js container (https://docs.mongodb.com/mongodb-shell/install/) and connect with

mongosh mongodb://mongo:27017/mongo

1. Also, when connecting to the same db from the Prisma installed at host machine with DATABASE_URL=“mongodb://localhost:27017/mongo” - everything works just fine.

Expected behavior

Prisma should be able to connect to the MongoDB, within docker-compose network, with the same connection string mongodb://mongo:27017/mongo as the other clients would (e.g. mongosh). There should be no difference between connecting to the mongodb://localhost:27017/mongo from the host machine or connecting to the mongodb://mongo:27017/mongo from the other container in the same docker-compose network.

Prisma information

datasource db {
  provider = "mongodb"
  url      = "mongodb://root:prisma@mongo:27018/admin"
}

generator client {
  provider        = "prisma-client-js"
  previewFeatures = ["mongodb"]
}

Environment & setup

• OS: Mac OS, Ubuntu 20
• Database: MongoDB 4
• Node.js version: 16

Prisma Version

3.10.0-dev.66

[hermanmitish]

I was able to resolve it changing env variable in docker-compose (https://github.com/prisma/prisma/blob/main/docker/docker-compose.yml):

From:

  # Replica Set (required for Prisma Client)
  mongo:
    build: ./mongodb_replica
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: prisma
      MONGO_REPLICA_HOST: localhost
      MONGO_REPLICA_PORT: 27018
    ports:
      - '27018:27018'

To:

  # Replica Set (required for Prisma Client)
  mongo:
    build: ./mongodb_replica
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: prisma
      MONGO_REPLICA_HOST: host.docker.internal
      MONGO_REPLICA_PORT: 27018
    ports:
      - '27018:27018'

[hermanmitish]

Yes, it seems so. Also, later on, I found out that it also works fine with

  mongo:
    build: ./mongodb_replica
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: prisma
      MONGO_REPLICA_HOST: mongo
      MONGO_REPLICA_PORT: 27018
    ports:
      - '27018:27018'

However, with this setup I can’t connect to the Mongo from host machine via the mongodb://localhost:27018/mongo, whatever the client. Which is not a big problem as far as MongoDB is easily reachable within docker-compose network, and which is not related to Prisma, but only to the dev setup.