micronaut

Micronaut is a modern, jvm-based, full-stack framework for building modular, easily testable microservice and serverless applications.

This describes how to build a simple JPA based web application using Micronaut framework for YSQL API using Yugabyte JDBC Driver.

Prerequisites

• Follow YB Quick start instructions to run a local YugabyteDB cluster. Test YugabyteDB's YSQL API, as documented so that you can confirm that you have YSQL service running on localhost:5433.
• You will need JDK 11 or above. You can use SDKMAN to install the JDK runtime.

Get Started

You can find the complete source at java framework with smart driver for YSQL. This project has directories for different java frameworks such as spring-boot, quarkus and micronaut. Clone this repository to a local workstation and open the yb-ms-data directory in your favorite IDE to easily navigate and explore Micronaut's project files.

git clone [REPO]

Dependencies

This project depends on the following libraries.

annotationProcessor("io.micronaut:micronaut-http-validation")
annotationProcessor("io.micronaut.data:micronaut-data-processor")
annotationProcessor("io.micronaut.openapi:micronaut-openapi")
implementation("io.micronaut:micronaut-http-client")
implementation("io.micronaut:micronaut-management")
implementation("io.micronaut:micronaut-runtime")
implementation("io.micronaut.data:micronaut-data-hibernate-jpa")
implementation("io.micronaut.flyway:micronaut-flyway")
implementation("io.micronaut.sql:micronaut-jdbc-hikari")
implementation("io.swagger.core.v3:swagger-annotations")
implementation("javax.annotation:javax.annotation-api")
runtimeOnly("ch.qos.logback:logback-classic")
implementation("io.micronaut:micronaut-validation")
implementation("com.yugabyte:jdbc-yugabytedb:42.3.5-yb-1")

Update the driver dependency library ("com.yugabyte:jdbc-yugabytedb") to the latest version. Grab the latest version from Yugabyte JDBC driver.

Driver Configuration

Refer to the file yb-ms-data/micronaut/src/main/resources/application.yaml in the project directory:

datasources:
  default:
    url: jdbc:yugabytedb://[hostname:port]/yugabyte
    driverClassName: com.yugabyte.Driver
    data-source-properties:
      load-balance: true
      currentSchema: todo
    username: yugabyte
    password: yugabyte
    minimum-idle: 5
    maximum-pool-size: 20

• url is the JDBC connection string.
• driverClassName is the JDBC driver class name.
• data-source-properties is where YugabyteDB driver specific properties such as load-balance and topology-keys can be set.

Update the JDBC url with the appropriate hostname and port number details jdbc:yugabytedb://[hostname:port]/yugabyte in the application.yaml file. Remember to remove the square brackets. It is just a place holder to indicate the fields that need user inputs.

Normal build and run

Navigate to yb-ms-data/micronaut folder in the project:

cd yb-ms-data/micronaut

To build the app:

gradle build

Run the app

To run & test the app:

gradle run

To run the app with ysql profile:

gradle -Dmicronaut.environments=ysql run

Native build and run (GraalVM: 20.0.1-graalce)

Navigate to yb-ms-data/micronaut folder in the project:

cd yb-ms-data/micronaut

To build the app:

gradle nativeOptimizedCompile

To run the app with ysql profile:

./build/native/nativeOptimizedCompile/yb-micronaut-data -Dmicronaut.environments=ysql