Gain insights into Quarkus, a modern Java framework. Learn about creating and configuring applications, REST endpoints, WebSockets, GraphQL, fault tolerance, and database connections for robust microservices.

quarkus.tar.gz

Quarkus run dev application

Quarkus test application

Quarkus run dev application + MongoDB

Quarkus run dev application + PostgreSQL

Quarkus is a modern Java framework that simplifies the creation of web applications. With the help of Quarkus, you can create modern applications and deploy them easily on the cloud.

You’ll begin the course with an introduction to Quarkus and the different features that make it a great Java framework. Next, you’ll explore the basics of Quarkus, such as creating and configuring an application, adding plugins, and testing your code. You’ll learn how to build modern web applications using Quarkus by creating and consuming REST endpoints and documenting them. You’ll also learn how to create a WebSocket server and a GraphQL endpoint and ensure fault tolerance for your application. Lastly,  you’ll add different kinds of database connections to your Quarkus application.

After completing this course, you’ll be equipped to create various applications and microservices using Quarkus, a must-have knowledge for any developer.

Developing Microservices with Quarkus

To ensure a bug-free and robust application, we need to thoroughly test it. This can be done by manual testing or by automating the task with scripts and code. We’ll explore how this can be done with Quarkus.

# Example app

Let's start by creating a new application with the below command:

mvn io.quarkus.platform:quarkus-maven-plugin:2.15.3.Final:create -DprojectGroupId=io.educative -DprojectArtifactId=educative-quarkus

The code generated is available via the playground below:

*
!target/*-runner
!target/*-runner.jar
!target/lib/*
!target/quarkus-app/*

#Maven
target/
pom.xml.tag
pom.xml.releaseBackup
pom.xml.versionsBackup
release.properties
.flattened-pom.xml

# Eclipse
.project
.classpath
.settings/
bin/

# IntelliJ
.idea
*.ipr
*.iml
*.iws

# NetBeans
nb-configuration.xml

# Visual Studio Code
.vscode
.factorypath

# OSX
.DS_Store

# Vim
*.swp
*.swo

# patch
*.orig
*.rej

# Local environment
.env


<?xml version="1.0"?>
<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <modelVersion>4.0.0</modelVersion>
  <groupId>io.educative</groupId>
  <artifactId>educative-quarkus</artifactId>
  <version>1.0.0-SNAPSHOT</version>
  <properties>
    <compiler-plugin.version>3.10.1</compiler-plugin.version>
    <maven.compiler.release>17</maven.compiler.release>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <quarkus.platform.artifact-id>quarkus-bom</quarkus.platform.artifact-id>
    <quarkus.platform.group-id>io.quarkus.platform</quarkus.platform.group-id>
    <quarkus.platform.version>3.6.5</quarkus.platform.version>
    <skipITs>true</skipITs>
    <surefire-plugin.version>3.0.0-M7</surefire-plugin.version>
  </properties>
  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>${quarkus.platform.group-id}</groupId>
        <artifactId>${quarkus.platform.artifact-id}</artifactId>
        <version>${quarkus.platform.version}</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
    </dependencies>
  </dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>io.quarkus</groupId>
      <artifactId>quarkus-arc</artifactId>
    </dependency>
    <dependency>
      <groupId>io.quarkus</groupId>
      <artifactId>quarkus-resteasy-reactive</artifactId>
    </dependency>
    <dependency>
      <groupId>io.quarkus</groupId>
      <artifactId>quarkus-junit5</artifactId>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>io.rest-assured</groupId>
      <artifactId>rest-assured</artifactId>
      <scope>test</scope>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <groupId>${quarkus.platform.group-id}</groupId>
        <artifactId>quarkus-maven-plugin</artifactId>
        <version>${quarkus.platform.version}</version>
        <extensions>true</extensions>
        <executions>
          <execution>
            <goals>
              <goal>build</goal>
              <goal>generate-code</goal>
              <goal>generate-code-tests</goal>
            </goals>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>${compiler-plugin.version}</version>
        <configuration>
          <compilerArgs>
            <arg>-parameters</arg>
          </compilerArgs>
        </configuration>
      </plugin>
      <plugin>
        <artifactId>maven-surefire-plugin</artifactId>
        <version>${surefire-plugin.version}</version>
        <configuration>
          <systemPropertyVariables>
            <java.util.logging.manager>org.jboss.logmanager.LogManager</java.util.logging.manager>
            <maven.home>${maven.home}</maven.home>
          </systemPropertyVariables>
        </configuration>
      </plugin>
      <plugin>
        <artifactId>maven-failsafe-plugin</artifactId>
        <version>${surefire-plugin.version}</version>
        <executions>
          <execution>
            <goals>
              <goal>integration-test</goal>
              <goal>verify</goal>
            </goals>
            <configuration>
              <systemPropertyVariables>
                <native.image.path>${project.build.directory}/${project.build.finalName}-runner</native.image.path>
                <java.util.logging.manager>org.jboss.logmanager.LogManager</java.util.logging.manager>
                <maven.home>${maven.home}</maven.home>
              </systemPropertyVariables>
            </configuration>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
  <profiles>
    <profile>
      <id>native</id>
      <activation>
        <property>
          <name>native</name>
        </property>
      </activation>
      <properties>
        <skipITs>false</skipITs>
        <quarkus.package.type>native</quarkus.package.type>
      </properties>
    </profile>
  </profiles>
</project>


# educative-quarkus

This project uses Quarkus, the Supersonic Subatomic Java Framework.

If you want to learn more about Quarkus, please visit its website: https://quarkus.io/ .

## Running the application in dev mode

You can run your application in dev mode that enables live coding using:
```shell script
./mvnw compile quarkus:dev
```

> **_NOTE:_**  Quarkus now ships with a Dev UI, which is available in dev mode only at http://localhost:8080/q/dev/.

## Packaging and running the application

The application can be packaged using:
```shell script
./mvnw package
```
It produces the `quarkus-run.jar` file in the `target/quarkus-app/` directory.
Be aware that it’s not an _über-jar_ as the dependencies are copied into the `target/quarkus-app/lib/` directory.

The application is now runnable using `java -jar target/quarkus-app/quarkus-run.jar`.

If you want to build an _über-jar_, execute the following command:
```shell script
./mvnw package -Dquarkus.package.type=uber-jar
```

The application, packaged as an _über-jar_, is now runnable using `java -jar target/*-runner.jar`.

## Creating a native executable

You can create a native executable using: 
```shell script
./mvnw package -Pnative
```

Or, if you don't have GraalVM installed, you can run the native executable build in a container using: 
```shell script
./mvnw package -Pnative -Dquarkus.native.container-build=true
```

You can then execute your native executable with: `./target/educative-quarkus-1.0.0-SNAPSHOT-runner`

If you want to learn more about building native executables, please consult https://quarkus.io/guides/maven-tooling.

## Provided Code

### RESTEasy Reactive

Easily start your Reactive RESTful Web Services

[Related guide section...](https://quarkus.io/guides/getting-started-reactive#reactive-jax-rs-resources)


import React from 'react';
import { shallow, configure } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';

configure({ adapter: new Adapter() });

import HelloWorld from './app';

var TestResult = function() {
    this.succeeded = false;
    this.reason = "";
    this.input = "";
    this.expected_output = "";
    this.actual_output = "";
}

export const executeTests = function() {

  var results = [];

  result = new TestResult();
  result.input = 'HelloWorld Component';
  result.expected_output = "span containing text 'Hello World'"

  let wrapper = shallow(<HelloWorld />);

  // Call your Challenge function here.

  let type = wrapper.type();
  let testSuccessful = true;
  let failureReason;

  if (type !== 'span') {
    testSuccessful = false;
    failureReason = "You need to render exactly one span HTML element";
  } else if (wrapper.props().children != "Hello World") {
     testSuccessful = false;
     failureReason = "You have rendered wrong message in your span element";
  }

  result.actual_output = wrapper.html();

  if (testSuccessful) {
    result.succeeded = true;
    result.reason = "Succeeded"
  } else {
    result.succeeded = false;
    result.reason = failureReason;
  }

  results.push(result);

  return results;
}


React

Dart

GoJS React

Typescript React

Vue.js

# HTTP testing

To start testing our endpoints, we’ll use the `rest-assured` extension along with the `quarkus-junit5` extension.

Let's start by creating a new class called `GreetingResourceTest` that will contain our tests.

We need to add the `@QuarkusTest`annotation, which will mark our class as a Quarkus test. Then, we can mark each test with the `@Test` annotation.

Let’s consider the below example with our playground:

Learn how to test the Quarkus application.

Introduction to Quarkus

Quarkus Basics

Quarkus Web

Quarkus Data

Epilogue

Appendix

Testing a Quarkus Application

Example app