To use a database in go you must create a struct that implements either the ftl.MySQLDatabaseConfig or ftl.PostgresDatabaseConfig interface. Generally this will involve creating a struct that embeds the ftl.DefaultMySQLDatabaseConfig or ftl.DefaultPostgresDatabaseConfig struct and then implementing the Name() string method.

You can then use the ftl.DatabaseHandle type to access the database by injecting it into an FTL verb. An example for MySQL is shown below:

package mysql

import (
	"context"
	"database/sql"

	"github.com/block/ftl/go-runtime/ftl" // Import the FTL SDK.
)

type TestDatasourceConfig struct {
	ftl.DefaultMySQLDatabaseConfig
}

func (TestDatasourceConfig) Name() string { return "testdb" }

//ftl:verb export
func Query(ctx context.Context, db ftl.DatabaseHandle[TestDatasourceConfig]) ([]string, error) {
	var database *sql.DB = db.Get(ctx) // Get the database connection.
	// The following code is standard golang SQL code, it has nothing FTL specific.
	rows, err := database.QueryContext(ctx, "SELECT data FROM requests")
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var items []string
	for rows.Next() {
		var i string
		if err := rows.Scan(
			&i,
		); err != nil {
			return nil, err
		}
		items = append(items, i)
	}
	if err := rows.Close(); err != nil {
		return nil, err
	}
	if err := rows.Err(); err != nil {
		return nil, err
	}
	return items, nil
}

To declare a datasource in Kotlin you must create an application.properties file in the src/main/resources directory. Datasources currently leverage the Quarkus Database extension, and so databases are configured using Quarkus config. To define a MySQL database using the Quarkus Hibernate extension you would do the following:

quarkus.datasource.testdb.db-kind=mysql
quarkus.hibernate-orm.datasource=testdb

To use this in your FTL code you can then just use Hibernate directly or using Panache.

Note that this will likely change significantly in future once FTL has SQL Verbs.

To declare a datasource in Java you must create an application.properties file in the src/main/resources directory. Datasources currently leverage the Quarkus Database extension, and so databases are configured using Quarkus config. To define a MySQL database using the Quarkus Hibernate extension you would do the following:

quarkus.datasource.testdb.db-kind=mysql
quarkus.hibernate-orm.datasource=testdb

To use this in your FTL code you can then just use Hibernate directly or using Panache.

Note that this will likely change significantly in future once FTL has SQL Verbs.

An example showing DB usage with Pachance is shown below:

package xyz.block.ftl.java.test.database;

import java.util.List;
import java.util.Map;

import jakarta.transaction.Transactional;
import jakarta.persistence.Entity;
import jakarta.persistence.Table;

import xyz.block.ftl.Verb;

import io.quarkus.hibernate.orm.panache.PanacheEntity;

public class Database {
    
    @Verb
    @Transactional
    public List<Request> query() {
        List<Request> requests = Request.listAll();
        return requests;
    }
}


@Entity
@Table(name = "requests")
public class Request extends PanacheEntity {
    public String data;
    
}