Kotlin Exposed Table Generator Gradle Plugin

Overview

The Kotlin Exposed Table Generator is a Gradle plugin designed to generate Kotlin Exposed table definitions directly from a PostgreSQL database schema. Simplify your workflow by automating the creation of table mappings and keeping them in sync with your database.

Features

• Generate Kotlin Exposed DSL table definitions.
• Filter tables by schema for precise control.
• Keep your code synchronized with database schema changes effortlessly.

Installation

Add the plugin to your build.gradle.kts:

plugins {
    id("io.github.klahap.pgen") version "$VERSION"
}

Configuration

To configure the plugin, add the pgen block to your build.gradle.kts:

pgen {
    dbConnectionConfig(
        url = System.getenv("DB_URL"),          // Database URL
        user = System.getenv("DB_USER"),        // Database username
        password = System.getenv("DB_PASSWORD") // Database password
    )
    packageName("io.example.db")                // Target package for generated tables
    tableFilter {
        addSchemas("public")                    // Include only specific schemas (e.g., "public")
    }
    outputPath("./output")                      // Output directory for generated files
}

Environment Variables

Make sure to set the following environment variables:

• DB_URL: The connection URL for your PostgreSQL database.
• DB_USER: Your database username.
• DB_PASSWORD: Your database password.

Running the Plugin

Once configured, generate your Kotlin Exposed table definitions by running:

./gradlew pgen

This will create Kotlin files in the specified outputPath.

Example

Input: Database Schema

Assume a PostgreSQL schema with the following table:

CREATE TYPE status AS ENUM ('ACTIVE', 'INACTIVE');

CREATE TABLE users
(
    id     SERIAL PRIMARY KEY,
    name   TEXT NOT NULL,
    status status
);

Output: Generated Kotlin File

The plugin will generate a Kotlin Exposed DSL table:

package io.example.db

import org.jetbrains.exposed.sql.Table

enum class Status(
    override val pgEnumLabel: String,
) : PgEnum {
    ACTIVE(pgEnumLabel = "ACTIVE"),
    INACTIVE(pgEnumLabel = "INACTIVE");

    override val pgEnumTypeName: String = "public.status"
}

object Users : Table("users") {
    val id: Column<Int> = integer(name = "id")
    val name: Column<String> = text(name = "name")
    val status: Column<Status> = customEnumeration(
        name = "status",
        sql = "status",
        fromDb = { getPgEnumByLabel(it as String) },
        toDb = { it.toPgObject() },
    )

    override val primaryKey: Table.PrimaryKey = PrimaryKey(id, name = "users_pkey")
}

Contributing

Contributions are welcome! Feel free to open issues or submit pull requests to improve the plugin.

License

This project is licensed under the MIT License.