Can vertx and traditional jdbc clients work together in quarkus? - quarkus

Question

In my quarkus project, I have added the following dependencies to create a non-blocking asynchronous project
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-vertx</artifactId>
</dependency>
<dependency>
<groupId>io.smallrye.reactive</groupId>
<artifactId>smallrye-mutiny-vertx-web-client</artifactId>
</dependency>
But now I want to write data to mysql database, so I want to add the following dependency to the project
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-hibernate-orm-panache</artifactId>
</dependency>
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-jdbc-mysql</artifactId>
</dependency>
But it seems that this database driver and orm are blocking, so what I want to ask is, does vert.x work with traditional jdbc in quarkus?
Another question is, is the quarkus framework an asynchronous, non-blocking framework? What is its relationship to vert.x? When the qurakus framework Added vert.x dependency, did the whole project require non-blocking?

Answer 1

Quarkus can be reactive or non reactive, it depends which extensions you choose to use.
Hibernate ORM Panache is for when you want to access the database in a non reactive way using Hibernate ORM and Panache.
The same is true for JDBC, it's not reactive so you have to use something else if you want your whole app to be reactive.
In this scenario, you probably want to try these two extensions:
quarkus-hibernate-reactive-panache: See the Hibernate Reactive with panache quickstart for an example
quarkus-reactive-mysql-client: For allowing reactive access to the db. See the guide for Vert.x SQL Clients on the quarkus website
On the Quarkus website, there is also an intro on reactive for Quarkus.
Example of how to use the Vert.x SQL client from the guide:
#Path("fruits")
public class FruitResource {
#Inject
io.vertx.mutiny.mysqlclient.MySQLPool client;
}
client.query("DROP TABLE IF EXISTS fruits").execute()
.flatMap(r -> client.query("CREATE TABLE fruits (id SERIAL PRIMARY KEY, name TEXT NOT NULL)").execute())
.flatMap(r -> client.query("INSERT INTO fruits (name) VALUES ('Orange')").execute())
.flatMap(r -> client.query("INSERT INTO fruits (name) VALUES ('Pear')").execute())
.flatMap(r -> client.query("INSERT INTO fruits (name) VALUES ('Apple')").execute())
.await().indefinitely();
Example with Hibernate Reactive and Panache from the quickstart:
#Entity
public class Fruit extends PanacheEntity {
#Column(length = 40, unique = true)
public String name;
public Fruit() {
}
public Fruit(String name) {
this.name = name;
}
}
#GET
public Uni<List<Fruit>> get() {
return Fruit.listAll(Sort.by("name"));
}
A complete list of quickstarts for Quarkus is available on GitHub.
Look for the ones with the word reactive and you will have several examples with different extensions.
To conclude, one approach is to replace the Hibernate ORM and JDBC extensions with the following:
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-hibernate-reactive-panache</artifactId>
</dependency>
<dependency>
<groupId>io.quarkus</groupId>
<artifactId>quarkus-reactive-mysql-client</artifactId>
</dependency>
Answer to your questions:
is the quarkus framework an asynchronous, non-blocking framework? What is its relationship to vert.x?
Quarkus is designed to work with popular Java standards, frameworks, and libraries. So, it being reactive or not depends from which extensions you pick and how you design your app. Vert.x is one of the tools that are available to you (See What's Quakrkus?)
When the quarkus framework Added vert.x dependency, did the whole project require non-blocking?
No. For example, you can have both the JDBC driver and the Vert.x SQL client extensions on the classpath and get one or the other via injection when you need to use them.