Connect from Cloud Run functions

import os

import sqlalchemy


def connect_tcp_socket() -> sqlalchemy.engine.base.Engine:
    """Initializes a TCP connection pool for a Cloud SQL instance of SQL Server."""
    # Note: Saving credentials in environment variables is convenient, but not
    # secure - consider a more secure solution such as
    # Cloud Secret Manager (https://cloud.google.com/secret-manager) to help
    # keep secrets safe.
    db_host = os.environ[
        "INSTANCE_HOST"
    ]  # e.g. '127.0.0.1' ('172.17.0.1' if deployed to GAE Flex)
    db_user = os.environ["DB_USER"]  # e.g. 'my-db-user'
    db_pass = os.environ["DB_PASS"]  # e.g. 'my-db-password'
    db_name = os.environ["DB_NAME"]  # e.g. 'my-database'
    db_port = os.environ["DB_PORT"]  # e.g. 1433

    pool = sqlalchemy.create_engine(
        # Equivalent URL:
        # mssql+pytds://<db_user>:<db_pass>@<db_host>:<db_port>/<db_name>
        sqlalchemy.engine.url.URL.create(
            drivername="mssql+pytds",
            username=db_user,
            password=db_pass,
            database=db_name,
            host=db_host,
            port=db_port,
        ),
        # ...
    )

    return pool

import com.zaxxer.hikari.HikariConfig;
import com.zaxxer.hikari.HikariDataSource;
import javax.sql.DataSource;

public class TcpConnectionPoolFactory extends ConnectionPoolFactory {

  // Note: Saving credentials in environment variables is convenient, but not
  // secure - consider a more secure solution such as
  // Cloud Secret Manager (https://cloud.google.com/secret-manager) to help
  // keep secrets safe.
  private static final String DB_USER = System.getenv("DB_USER");
  private static final String DB_PASS = System.getenv("DB_PASS");
  private static final String DB_NAME = System.getenv("DB_NAME");

  private static final String INSTANCE_HOST = System.getenv("INSTANCE_HOST");
  private static final String DB_PORT = System.getenv("DB_PORT");


  public static DataSource createConnectionPool() {
    // The configuration object specifies behaviors for the connection pool.
    HikariConfig config = new HikariConfig();

    // Configure which instance and what database user to connect with.
    config.setJdbcUrl(
        String.format("jdbc:sqlserver://%s:%s;databaseName=%s", INSTANCE_HOST, DB_PORT, DB_NAME));
    config.setUsername(DB_USER); // e.g. "root", "sqlserver"
    config.setPassword(DB_PASS); // e.g. "my-password"


    // ... Specify additional connection properties here.
    // ...

    // Initialize the connection pool using the configuration object.
    return new HikariDataSource(config);
  }
}

const mssql = require('mssql');

// createTcpPool initializes a TCP connection pool for a Cloud SQL
// instance of SQL Server.
const createTcpPool = async config => {
  // Note: Saving credentials in environment variables is convenient, but not
  // secure - consider a more secure solution such as
  // Cloud Secret Manager (https://cloud.google.com/secret-manager) to help
  // keep secrets safe.
  const dbConfig = {
    server: process.env.INSTANCE_HOST, // e.g. '127.0.0.1'
    port: parseInt(process.env.DB_PORT), // e.g. 1433
    user: process.env.DB_USER, // e.g. 'my-db-user'
    password: process.env.DB_PASS, // e.g. 'my-db-password'
    database: process.env.DB_NAME, // e.g. 'my-database'
    options: {
      trustServerCertificate: true,
    },
    // ... Specify additional properties here.
    ...config,
  };
  // Establish a connection to the database.
  return mssql.connect(dbConfig);
};

package cloudsql

import (
	"database/sql"
	"fmt"
	"log"
	"os"
	"strings"

	_ "github.com/denisenkom/go-mssqldb"
)

// connectTCPSocket initializes a TCP connection pool for a Cloud SQL
// instance of SQL Server.
func connectTCPSocket() (*sql.DB, error) {
	mustGetenv := func(k string) string {
		v := os.Getenv(k)
		if v == "" {
			log.Fatalf("Fatal Error in connect_tcp.go: %s environment variable not set.\n", k)
		}
		return v
	}
	// Note: Saving credentials in environment variables is convenient, but not
	// secure - consider a more secure solution such as
	// Cloud Secret Manager (https://cloud.google.com/secret-manager) to help
	// keep secrets safe.
	var (
		dbUser    = mustGetenv("DB_USER")       // e.g. 'my-db-user'
		dbPwd     = mustGetenv("DB_PASS")       // e.g. 'my-db-password'
		dbTCPHost = mustGetenv("INSTANCE_HOST") // e.g. '127.0.0.1' ('172.17.0.1' if deployed to GAE Flex)
		dbPort    = mustGetenv("DB_PORT")       // e.g. '1433'
		dbName    = mustGetenv("DB_NAME")       // e.g. 'my-database'
	)

	dbURI := fmt.Sprintf("server=%s;user id=%s;password=%s;port=%s;database=%s;",
		dbTCPHost, dbUser, dbPwd, dbPort, dbName)


	// dbPool is the pool of database connections.
	dbPool, err := sql.Open("sqlserver", dbURI)
	if err != nil {
		return nil, fmt.Errorf("sql.Open: %w", err)
	}

	// ...

	return dbPool, nil
}

namespace Google\Cloud\Samples\CloudSQL\SQLServer;

use PDO;
use PDOException;
use RuntimeException;
use TypeError;

class DatabaseTcp
{
    public static function initTcpDatabaseConnection(): PDO
    {
        try {
            // Note: Saving credentials in environment variables is convenient, but not
            // secure - consider a more secure solution such as
            // Cloud Secret Manager (https://cloud.google.com/secret-manager) to help
            // keep secrets safe.
            $username = getenv('DB_USER'); // e.g. 'your_db_user'
            $password = getenv('DB_PASS'); // e.g. 'your_db_password'
            $dbName = getenv('DB_NAME'); // e.g. 'your_db_name'
            $instanceHost = getenv('INSTANCE_HOST'); // e.g. '127.0.0.1' ('172.17.0.1' for GAE Flex)

            // Connect using TCP
            $dsn = sprintf(
                'sqlsrv:server=%s;Database=%s',
                $instanceHost,
                $dbName
            );

            // Connect to the database
            $conn = new PDO(
                $dsn,
                $username,
                $password,
                # ...
            );
        } catch (TypeError $e) {
            throw new RuntimeException(
                sprintf(
                    'Invalid or missing configuration! Make sure you have set ' .
                        '$username, $password, $dbName, and $instanceHost (for TCP mode). ' .
                        'The PHP error was %s',
                    $e->getMessage()
                ),
                $e->getCode(),
                $e
            );
        } catch (PDOException $e) {
            throw new RuntimeException(
                sprintf(
                    'Could not connect to the Cloud SQL Database. Check that ' .
                        'your username and password are correct, that the Cloud SQL ' .
                        'proxy is running, and that the database exists and is ready ' .
                        'for use. For more assistance, refer to %s. The PDO error was %s',
                    'https://cloud.google.com/sql/docs/sqlserver/connect-external-app',
                    $e->getMessage()
                ),
                (int) $e->getCode(),
                $e
            );
        }

        return $conn;
    }
}