vatn-plugin-postgres

vatn-plugin-postgres

Provides a HikariCP-managed PostgreSQL connection pool as a VATN service.

How it works

Initialises a HikariCP DataSource at plugin startup using the supplied connection parameters. A postgres health check is registered with the VATN node via ctx.registerHealthCheck, so the admin dashboard and health endpoints reflect database reachability. DataSourceService exposes both the raw HikariDataSource for framework integration and a getConnection() shortcut for direct JDBC use. The pool is closed cleanly on node shutdown.

Setup

<dependency>
    <groupId>dev.vatn.plugins</groupId>
    <artifactId>vatn-plugin-postgres</artifactId>
    <version>1.0-alpha.12</version>
</dependency>

PostgresConfig config = PostgresConfig.of("localhost", 5432, "mydb", "app", "secret")
    .withPoolSize(10)
    .withSchema("public")
    .withSsl(true);

VNodeRunner.create()
    .addPlugin(new PostgresPlugin(config))
    .run();

API

public interface DataSourceService {
    HikariDataSource dataSource();
    Connection       getConnection() throws SQLException;
}

DataSourceService ds = ctx.service(DataSourceService.class);

// Direct JDBC
try (Connection conn = ds.getConnection();
     PreparedStatement ps = conn.prepareStatement("SELECT id, name FROM users WHERE id = ?")) {
    ps.setLong(1, userId);
    try (ResultSet rs = ps.executeQuery()) {
        if (rs.next()) System.out.println(rs.getString("name"));
    }
}

// Framework integration (e.g. jOOQ, JDBI)
DSLContext jooq = DSL.using(ds.dataSource(), SQLDialect.POSTGRES);

Configuration

Option	Default	Meaning
host	—	PostgreSQL server hostname
port	—	PostgreSQL server port (typically 5432)
database	—	Database name
username	—	Authentication username
password	—	Authentication password
poolSize	HikariCP default (10)	Maximum number of connections in the pool
schema	not set	Default schema (search_path)
ssl	false	Enable SSL/TLS for the JDBC connection

Notes

• Connections borrowed from the pool must be closed (try-with-resources) to return them to the pool; leaking connections will exhaust the pool.
• The registered postgres health check executes a lightweight SELECT 1 against the pool.
• dataSource() returns the HikariDataSource directly, which exposes pool statistics via getHikariPoolMXBean().
• SSL mode uses the PostgreSQL JDBC driver's default verify-full when withSsl(true) is set; supply a truststore via JVM system properties if your CA is not in the default truststore.