I will leave a summary of the contents that confirmed the usability of Quarkus, which is a hot topic in the streets. Only Get Started was not enough, so I tried to make PostgreSQL that was set up locally as a REST Web API that operates with Hibernate.
Complete QUARKUS --CREATING YOUR FIRST APPLICATION first. The state of the project looks like this.
$ tree ./
./
├── pom.xml
├── quarkus_quickstart.iml
└── src
├── main
│ ├── docker
│ │ └── Dockerfile
│ ├── java
│ │ └── com
│ │ └── dsert
│ │ └── quickstart
│ │ ├── GreetingResource.java
│ │ └── GreetingService.java
│ └── resources
│ ├── META-INF
│ │ ├── microprofile-config.properties
│ │ └── resources
│ │ └── index.html
│ └── application.properties
└── test
└── java
└── com
└── dsert
└── quickstart
├── GreetingResourceTest.java
└── NativeGreetingResourceIT.java
PostgreSQL Make a table or something like that. The DDL generated by IntelliJ looks like the following.
create database quarkus with owner quarkus;
create table if not exists users
(
id serial not null
constraint users_pk
primary key,
name varchar(255) not null
);
Add the Hibernate and PostgreSQL dependencies to pom.xml, referring to the QUARKUS --EXTENSIONS section.
Also, since the request and response in JSON is not possible with the dependency as Get Started, change quarkus-resteasy to quarkus-resteasy-jsonb.
pom.xml
<dependencies>
...
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-resteasy-jsonb</artifactId>
</dependency>
<!-- Hibernate ORM specific dependencies -->
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-hibernate-orm</artifactId>
<scope>provided</scope>
</dependency>
<!-- JDBC driver dependencies -->
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-jdbc-postgresql</artifactId>
<scope>provided</scope>
</dependency>
</dependencies>
As described in QUARKUS --APPLICATION CONFIGURATION GUIDE, you can manage environment values in application.properties. Describe the information required for DB connection as follows.
src/main/resources/application.properties
quarkus.datasource.url: jdbc:postgresql://localhost:5432/quarkus
quarkus.datasource.driver: org.postgresql.Driver
quarkus.datasource.username: quarkus
quarkus.datasource.password: quarkus-pass
Entity Create an Entity object that fits the table to map the data.
src/main/java/com/dsert/quickstart/User.java
package com.dsert.quickstart;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
@Entity(name = "users")
public class User {
private int id;
private String name;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Service Create a service class that operates the DB.
src/main/java/com/dsert/quickstart/UserService.java
package com.dsert.quickstart;
import javax.enterprise.context.ApplicationScoped;
import javax.inject.Inject;
import javax.persistence.EntityManager;
import javax.transaction.Transactional;
import java.util.List;
@ApplicationScoped
public class UserService {
@Inject
EntityManager em;
@Transactional
public void createUser(String name) {
User user = new User();
user.setName(name);
this.em.persist(user);
}
public List<User> getUsers() {
return this.em.createNativeQuery("select * from users", User.class).getResultList();
}
}
Resource Create a resource class that handles HTTP requests.
src/main/java/com/dsert/quickstart/UserResource.java
package com.dsert.quickstart;
import javax.inject.Inject;
import javax.ws.rs.*;
import javax.ws.rs.core.MediaType;
import java.util.Collections;
import java.util.List;
import java.util.Map;
@Path("/users")
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public class UserResource {
@Inject
UserService service;
@POST
public Map<String, String> createUser(User user) {
this.service.createUser(user.getName());
return Collections.singletonMap("message", "OK");
}
@GET
public List<User> getUsers() {
return this.service.getUsers();
}
}
I want to start it easily, so I start it in development mode instead of DockerImage.
mvn compile quarkus:dev 6.2m
[INFO] Scanning for projects...
[INFO]
[INFO] -------------------< com.d-sert:quarkus_quickstart >--------------------
[INFO] Building quarkus_quickstart 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ quarkus_quickstart ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 3 resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ quarkus_quickstart ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] --- quarkus-maven-plugin:0.11.0:dev (default-cli) @ quarkus_quickstart ---
[INFO] Using servlet resources quarkus_quickstart/src/main/resources/META-INF/resources
Listening for transport dt_socket at address: 5005
2019-03-13 08:49:58,673 INFO [io.qua.dep.QuarkusAugmentor](main) Beginning quarkus augmentation
2019-03-13 08:49:59,282 INFO [io.qua.dep.QuarkusAugmentor](main) Quarkus augmentation completed in 609ms
2019-03-13 08:50:05,128 INFO [io.quarkus](main) Quarkus 0.11.0 started in 6.638s. Listening on: http://127.0.0.1:8080
2019-03-13 08:50:05,130 INFO [io.quarkus](main) Installed features: [agroal, cdi, hibernate-orm, jdbc-postgresql, narayana-jta, resteasy, resteasy-jsonb]
POST
$ curl -X POST -H 'Content-Type: application/json' 'http://localhost:8080/users' -d '{"name": "sert"}'
{"message":"OK"}
GET
$ curl 'http://localhost:8080/users'
[{"id":5,"name":"sert"}]
I really wanted to connect to MySQL, but the MySQL driver is not in the Extension, I did it with PostgreSQL because I couldn't connect well with MariaDB Driver. I will try to revenge with MySQL soon.
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