When Cube runs dbType configuration callback function it sometimes try to find dataSource: undefined

[ipipos56]

Describe the bug
Sometimes when Cube is running it tries to getDbType with dataSource: undefined

To Reproduce
Steps to reproduce the behavior:

1. Make simple cube.ts as mine
2. Add simple .env as mine
3. Add simple postgres init.sql as mine in init/init.sql
4. Add simple docker-compose as mine to run cube and postgres
5. Add simple esbuild.config.ts as mine to build cube.ts file
6. Run tsx ./esbuild.config.ts and docker compose up
7. Wait until sheduler starts his process
8. See "datasource: undefined" in dbType calls

Expected behavior
dbType calls with correct dataSource and do not calls with dataSource: undefined

Logs

pnpm start:dev

> cube@0.0.1 start:dev /cube
> pnpm build && docker compose up


> cube@0.0.1 build /cube
> tsx ./esbuild.config.ts

Build complete!
WARN[0000] Found orphan containers ([cube-postgres-test-1]) for this project. If you removed or renamed this service in your compose file, you can run this command with the --remove-orphans flag to clean it up. 
[+] Running 4/4
 ✔ Network cube_default                                            Created                                                                         0.0s 
 ✔ Container test-postgres                                         Created                                                                         0.0s 
 ✔ Container cube-cube-1                                           Created                                                                         0.0s 
 ! cube Published ports are discarded when using host network mode                                                                                 0.0s 
Attaching to cube-1, test-postgres
test-postgres  | 
test-postgres  | PostgreSQL Database directory appears to contain a database; Skipping initialization
test-postgres  | 
test-postgres  | 2026-04-15 14:52:14.853 UTC [1] LOG:  starting PostgreSQL 15.17 (Debian 15.17-1.pgdg13+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 14.2.0-19) 14.2.0, 64-bit
test-postgres  | 2026-04-15 14:52:14.853 UTC [1] LOG:  listening on IPv4 address "0.0.0.0", port 5432
test-postgres  | 2026-04-15 14:52:14.854 UTC [1] LOG:  listening on IPv6 address "::", port 5432
test-postgres  | 2026-04-15 14:52:14.855 UTC [1] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
test-postgres  | 2026-04-15 14:52:14.858 UTC [30] LOG:  database system was shut down at 2026-04-15 14:52:08 UTC
test-postgres  | 2026-04-15 14:52:14.862 UTC [1] LOG:  database system is ready to accept connections
cube-1         | 🔥 Cube Store (1.6.34) is assigned to 3030 port.
cube-1         | 🔓 Authentication checks are disabled in developer mode. Please use NODE_ENV=production to enable it.
cube-1         | 🦅 Dev environment available at http://localhost:4000
cube-1         | 🔗 Cube SQL (pg) is listening on 0.0.0.0:15432
cube-1         | 🚀 Cube API server (1.6.34) is listening on 4000
cube-1         | 2026-04-15T14:52:15.365Z INFO  [cubestored] <pid:22> Cube Store version 1.6.34
cube-1         | 2026-04-15T14:52:15.369Z INFO  [cubestore::http::status] <pid:22> Serving status probes at 0.0.0.0:3031
cube-1         | 2026-04-15T14:52:15.369Z INFO  [cubestore::metastore::rocks_fs] <pid:22> Using existing metastore in /cube/conf/.cubestore/data/metastore
cube-1         | 2026-04-15T14:52:15.378Z INFO  [cubestore::http] <pid:22> Http Server is listening on 0.0.0.0:3030
cube-1         | 2026-04-15T14:52:15.378Z INFO  [cubestore::mysql] <pid:22> MySQL port open on 0.0.0.0:13306
cube-1         | 2026-04-15T14:52:30.379Z INFO  [cubestore::metastore::rocks_fs] <pid:22> Using existing cachestore in /cube/conf/.cubestore/data/cachestore
cube-1         | Performing query: scheduler-d0224285-fbb0-4fc5-b2fa-3f4c1281123f
cube-1         | Executing SQL: scheduler-d0224285-fbb0-4fc5-b2fa-3f4c1281123f
cube-1         | --
cube-1         |   SELECT FLOOR((UNIX_TIMESTAMP()) / 10) as refresh_key
cube-1         | --
cube-1         | Performing query completed: scheduler-d0224285-fbb0-4fc5-b2fa-3f4c1281123f (9ms)
cube-1         | datasource:  undefined
cube-1         | Performing query: scheduler-f0434fbd-3394-489e-96e8-e822d8736771
cube-1         | Executing SQL: scheduler-f0434fbd-3394-489e-96e8-e822d8736771
cube-1         | --
cube-1         |   SELECT FLOOR((UNIX_TIMESTAMP()) / 10) as refresh_key
cube-1         | --
cube-1         | Performing query completed: scheduler-f0434fbd-3394-489e-96e8-e822d8736771 (2ms)
cube-1         | datasource:  undefined

Cube.ts

import type { CreateOptions } from '@cubejs-backend/server-core';
import { PostgresDriver } from '@cubejs-backend/postgres-driver';

const configuration: CreateOptions = {
  telemetry: false,

  repositoryFactory: () => {
    return {
      dataSchemaFiles: async () => {
        return [
          {
            fileName: 'TestCube.js',
            content: `
              cube(\`TestCube\`, {
                sql: \`SELECT * FROM users\`,
                
                dataSource: 'test-postgres',

                measures: {
                  count: {
                    type: 'count'
                  }
                },

                dimensions: {
                  id: {
                    sql: 'id',
                    type: 'number',
                    primaryKey: true
                  },
                  name: {
                    sql: 'name',
                    type: 'string'
                  }
                }
              });
            `,
          },
        ];
      },
    };
  },

  schemaVersion: async () => 'v1',

  dbType: async ({ dataSource }) => {
    if (!dataSource) console.log("datasource: ", dataSource);
    if (dataSource === 'test-postgres') {
      return 'postgres';
    }

    return 'sqlite';
  },

  driverFactory: async ({ dataSource }) => {
    return new PostgresDriver({
      host: 'localhost',
      port: 5432,
      database: 'test',
      user: 'postgres',
      password: 'postgres',
    });
  },
};

module.exports = configuration;

.env

CUBEJS_DEV_MODE=true
CUBEJS_API_SECRET=testApiToken

esbuild.config.ts

import esbuild from 'esbuild';

async function build() {
  const cubeFilePatterns = ['cube.ts'];
  await esbuild.build({
    entryPoints: cubeFilePatterns,
    format: 'cjs',
    outdir: 'dist',
    outbase: 'src',
    platform: 'node',
    target: 'es2022',
    packages: 'external',
  });
  console.log('Build complete!');
}

build();

docker-compose.yml

services:
  cube:
    image: cubejs/cube:v1.6.34
    ports:
      - 4000:4000
      - 3000:3000
    env_file: .env
    volumes:
      - ./dist:/cube/conf
      - .empty:/cube/conf/node_modules/@cubejs-backend/
    network_mode: host
  
  test-postgres:
    image: postgres:15
    container_name: test-postgres
    restart: always
    environment:
      POSTGRES_DB: test
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
    ports:
      - "5432:5432"
    volumes:
      - ./pg-data:/var/lib/postgresql/data
      - ./init:/docker-entrypoint-initdb.d

init.sql

CREATE TABLE users (
  id SERIAL PRIMARY KEY,
  name TEXT,
  email TEXT,
  created_at TIMESTAMP DEFAULT NOW()
);

INSERT INTO users (name, email) VALUES
  ('Alice', 'alice@example.com'),
  ('Bob', 'bob@example.com'),
  ('Charlie', 'charlie@example.com');

Version:
Cube: 1.6.34
pnpm: 10.11.0
npm: 10.9.4
node: v22.21.1

Additional Context
Here the package.json to exactly run commands as mine

package.json

{
  "name": "cube",
  "version": "0.0.1",
  "devDependencies": {
    "@cubejs-backend/postgres-driver": "1.6.34",
    "@cubejs-backend/schema-compiler": "1.6.34",
    "@cubejs-backend/server-core": "1.6.34",
    "esbuild": "0.27.2",
    "tsx": "4.21.0"
  },
  "private": true,
  "scripts": {
    "build": "tsx ./esbuild.config.ts",
    "start:dev": "pnpm build && docker compose up"
  },
  "template": "docker",
  "templateVersion": "1.6.7"
}

Remark
I am now is looking for Cube code in the cubejs-server-code folder and want to find where exact problem is. Also, if it would be possibe want to make PR with fix. So, I will write here my updates in this research