kora-database-jdbc

Kora Database JDBC

Kora sub-skill — obey the kora-v1 meta rules on every task: R0 ensure .kora-agent/ docs+examples are cloned · R1 read this sub-skill before writing code · R2 Kora APIs only — no Spring/Micronaut/Quarkus, no invented annotations or config keys · R3 journal any incorrect Kora usage. Add comments/Javadoc only if asked.

JDBC-based relational database access (PostgreSQL, MySQL, Oracle) with HikariCP. Repositories are @Repository interfaces whose implementations are generated at compile time by the annotation processor — no reflection, no runtime proxies.

Prefer synchronous repository signatures (Entity, @Nullable Entity, List<Entity>, UpdateCount). The blocking JDBC driver runs on the executor bound to JdbcDatabase; virtual threads or a fixed pool handle blocking efficiently. Reach for CompletionStage/Mono only when a downstream contract requires it.

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Quick Start

1. Dependencies (build.gradle)

dependencies {
    koraBom platform("ru.tinkoff.kora:kora-parent:1.2.19")
    annotationProcessor "ru.tinkoff.kora:annotation-processors"  // mandatory: generates *RepositoryImpl

    implementation "ru.tinkoff.kora:database-jdbc"
    implementation "ru.tinkoff.kora:config-hocon"
    implementation "ru.tinkoff.kora:logging-logback"

    implementation "org.postgresql:postgresql:42.7.7"  // JDBC driver is required (not bundled)
}

All ru.tinkoff.kora:* artifacts inherit their version from the kora-parent BOM — never pin them individually.

Kotlin: use ksp "ru.tinkoff.kora:symbol-processors" instead of annotationProcessor, and implementation("...") syntax.

2. Plug the module into @KoraApp

@KoraApp
public interface Application extends
        HoconConfigModule,
        LogbackModule,
        JdbcDatabaseModule { }

JdbcDatabaseModule provides JdbcDatabase, its JdbcConnectionFactory, and the JdbcDatabaseConfig reader bound to the db config section.