Unable to connect to Cloud SQL PostgreSQL from Cloud Run using Unix Domain Socket

Environment

• Google Cloud Run
• Cloud SQL PostgreSQL instance
• Node.js 18
• TypeORM
• Cloud SQL Auth Proxy (running in same container)

Current Setup

My Cloud Run service is configured with:

• VPC Connector: service-connector
• VPC Egress: all-traffic
• Cloud SQL connection: Added via --add-cloudsql-instances

Database configuration (TypeORM):

const config = {
  type: 'postgres',
  url: `postgresql://${process.env.DB_USER}:${process.env.DB_PASSWORD}@${process.env.DB_HOST}/${process.env.DB_NAME}`,
  extra: {
    idleTimeoutMillis: 60000,
    statement_timeout: 60000,
    connectionTimeoutMillis: 60000,
    keepAlive: true,
    ssl: false
  }
};

Environment variables:

• DB_HOST=/cloudsql/PROJECT:REGION:INSTANCE
• DB_USER and DB_PASSWORD are set from Secret Manager
• DB_NAME=***

Issue

The Cloud Run service fails to connect to the Cloud SQL instance. The logs show:

failed to connect to instance: error Dialing via SQL Proxy Client: Dial error: failed to dial (connection name = "PROJECT:REGION:INSTANCE"): dial tcp IP:3307: i/o timeout

What I've Tried

1. Using direct Unix socket path: /cloudsql/PROJECT:REGION:INSTANCE
2. Using TypeORM's native configuration with host and socketPath
3. Using pg package's connection string format
4. Verified VPC connector and Cloud SQL Auth Proxy configuration
5. Confirmed all environment variables are set correctly
6. Verified service account has necessary permissions

Question

What is the correct way to configure TypeORM to connect to Cloud SQL PostgreSQL from Cloud Run using Unix Domain Socket? The documentation examples seem to focus on MySQL, and the PostgreSQL examples often use TCP connections instead of Unix sockets.

Additional Context

• The same configuration works locally using Cloud SQL Auth Proxy
• The service account has the necessary IAM roles
• The Cloud SQL instance is in the same region as the Cloud Run service