How to Consume REST API in Quarkus

Hello everyone, today, we will learn how to consume REST API in Quarkus. Making HTTP requests is a core feature of programming, and is often one of the first things you want to do when learning new technology. For Java programmers, there are many ways to do it - core libraries in the JDK and third-party libraries.

Here, we will learn how to use the below technologies to consume REST API in Quarkus.
  • MP Rest Client 
  • JAX-RS Client 
  • ApacheHttpClient
  • Java 11 HttpClient 

Related topics,

Project Directory:



Maven Dependencies[pom.xml].

<?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>org.knf.dev.demo</groupId>
    <artifactId>quarku-consume-restful-service</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <properties>
        <compiler-plugin.version>3.8.1</compiler-plugin.version>
        <failsafe.useModulePath>false</failsafe.useModulePath>
        <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>2.7.3.Final
        </quarkus.platform.version>
        <surefire-plugin.version>3.0.0-M5
        </surefire-plugin.version>
    </properties>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>${quarkus.platform.group-id}</groupId>
                <artifactId>${quarkus.platform.artifact-id}
                </artifactId>
                <version>${quarkus.platform.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>io.quarkus</groupId>
            <artifactId>quarkus-rest-client</artifactId>
        </dependency>
        <dependency>
            <groupId>io.quarkus</groupId>
            <artifactId>quarkus-rest-client-jackson</artifactId>
        </dependency>
        <dependency>
            <groupId>io.quarkus</groupId>
            <artifactId>quarkus-apache-httpclient</artifactId>
        </dependency>
        <dependency>
            <groupId>io.quarkus</groupId>
            <artifactId>quarkus-arc</artifactId>
        </dependency>
        <dependency>
            <groupId>io.quarkus</groupId>
            <artifactId>quarkus-resteasy</artifactId>
        </dependency>
        <dependency>
            <groupId>io.quarkus</groupId>
            <artifactId>quarkus-junit5</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>io.rest-assured</groupId>
            <artifactId>rest-assured</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>${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>
        </plugins>
    </build>
    <profiles>
        <profile>
            <id>native</id>
            <activation>
                <property>
                    <name>native</name>
                </property>
            </activation>
            <build>
                <plugins>
                    <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>
            <properties>
                <quarkus.package.type>native</quarkus.package.type>
            </properties>
        </profile>
    </profiles>
</project>


Create a Post POJO class:

package org.knf.dev.demo.model;

public class Post {

    private String userId;
    private String id;
    private String body;
    private String title;

    public String getUserId() {
        return userId;
    }

    public void setUserId(String userId) {
        this.userId = userId;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getBody() {
        return body;
    }

    public void setBody(String body) {
        this.body = body;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public Post() {
    }

    public Post(String userId,
                String id, String body, String title) {
        this.userId = userId;
        this.id = id;
        this.body = body;
        this.title = title;
    }
}


Method 1. How to use MicroProfile Rest Client to consume REST APIs.

Create PostService:

package org.knf.dev.demo.mprestclientdemo;

import org.eclipse.microprofile.rest.client.inject.RegisterRestClient;
import org.knf.dev.demo.model.Post;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import java.util.List;

@Path("/posts")
/*
@RegisterRestClient allows Quarkus to know
that this interface is meant to be available for
CDI injection as a REST Client
 */
@RegisterRestClient
public interface PostService {

    @GET
    List<Post> fetchAllPosts();
}


Configure the base URL in application.properties

org.knf.dev.demo.mprestclientdemo.PostService/mp-rest/url = https://jsonplaceholder.typicode.com


Create PostResource

package org.knf.dev.demo.mprestclientdemo;

import org.eclipse.microprofile.rest.client.inject.RestClient;
import org.knf.dev.demo.model.Post;
import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import java.util.List;

@Path("/api/v1/mprestclient")
public class PostResource {

    @Inject
    @RestClient
    PostService postService;

    @GET
    @Path("/posts")
    public List<Post> fetchAllPosts() {
        return postService.fetchAllPosts();
    }
}


Method 2. How to use ApacheHttpClient to consume REST APIs.

Create HttpService

package org.knf.dev.demo.apachehttpclient;

import com.fasterxml.jackson.databind.ObjectMapper;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.knf.dev.demo.model.Post;
import javax.inject.Singleton;
import java.io.IOException;
import java.util.List;

@Singleton
public class HttpService {

    CloseableHttpClient httpClient = HttpClients.createDefault();

    public <T> List<T> fetchPosts(String url, Class<Post> responseType) 
            throws IOException {
        HttpGet request = new HttpGet(url);
        request.addHeader("content-type", "application/json");
        CloseableHttpResponse response = httpClient.execute(request);
        ObjectMapper objectMapper =
                new ObjectMapper();
        return objectMapper.
                readValue(response.getEntity().getContent(),
                        objectMapper.getTypeFactory().
               constructCollectionType(List.class, responseType));
    }
}


Create PostResource

package org.knf.dev.demo.apachehttpclient;

import org.knf.dev.demo.model.Post;
import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import java.io.IOException;
import java.util.List;

@Path("/api/v1/apachehttpclient")
public class PostResource {

    @Inject
    HttpService httpService;

    @GET
    @Path("/posts")
    public List<Post> fetchAllPosts() 
               throws IOException, InterruptedException {
        List<Post> posts = httpService.
                fetchPosts("https://jsonplaceholder.typicode.com/posts", 
                        Post.class);
        return posts;
    }
}


Method 3. How to use Java 11 HttpClient to consume REST APIs.

Create HttpService

package org.knf.dev.demo.newhttpclientdemo;

import com.fasterxml.jackson.databind.ObjectMapper;
import javax.inject.Singleton;
import java.io.IOException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.List;

@Singleton
public class HttpService {

    private final HttpClient httpClient = HttpClient.
            newBuilder().version(HttpClient.Version.HTTP_2).build();

    public <T> List<T> fetchPosts(String url, Class<T> responseType)
            throws InterruptedException, IOException {
        HttpRequest request = HttpRequest.newBuilder().GET().
                uri(URI.create(url)).header("Accept",
                        "application/json").build();
        HttpResponse<String> response =
                httpClient.send(request, HttpResponse.
                        BodyHandlers.ofString());
        ObjectMapper objectMapper =
                new ObjectMapper();
        return objectMapper.
                readValue(response.body(),
                        objectMapper.getTypeFactory().
                 constructCollectionType(List.class, responseType));
    }
}


Create PostResource

package org.knf.dev.demo.newhttpclientdemo;

import java.io.IOException;
import java.util.List;
import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import org.knf.dev.demo.model.Post;

@Path("/api/v1/httpclient")
public class PostResource {

    @Inject
    HttpService httpService;

    @GET
    @Path("/posts")
    public List<Post> fetchAllPosts() 
              throws IOException, InterruptedException {

        HttpService httpService = new HttpService();
        List<Post> posts = httpService.
          fetchPosts("https://jsonplaceholder.typicode.com/posts", 
                Post.class);
        return posts;
    }
}


Method 4. How to use JAX-RS Client to consume REST APIs.

Create PostResource

package org.knf.dev.demo.jaxrsclientdemo;

import org.knf.dev.demo.model.Post;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.core.GenericType;
import java.util.List;

@Path("/api/v1/jaxrsclient")
public class PostResource {

    private final Client client = 
                ClientBuilder.newBuilder().build();
    private final String url = 
               "https://jsonplaceholder.typicode.com/posts";

    @GET
    @Path("/posts")
    public List<Post> fetchAllPosts() {
        List<Post> posts = client.target(url).
                request().get(new GenericType<List<Post>>() {
        });
        return posts;
    }
}


Run the Quarkus Application

Build application  jar file: mvn clean package


Start the application: java -jar quarkus-run.jar

Test Case 1: Use ApacheHttpClient to consume REST APIs.


Test Case 2: Use JAX-RS Client to consume REST APIs.


Test Case 3: Use MicroProfile Rest Client to consume REST APIs.


Test Case 4: Use Java 11 HttpClient to consume REST APIs.




More related topics,

Kotlin + Quarkus

Popular posts from this blog

Spring boot video streaming example-HTML5

Image
Hello everyone, Today we will learn how to stream MP4 video using Spring Boot and Spring Web Flux.  The Source code download link is provided at the end of this post. New, Quarkus Practice User Interface   Project Structure: G radle(build.gradle) plugins { id 'org.springframework.boot' version '2.5.4' id 'io.spring.dependency-management' version '1.0.11.RELEASE' id 'java' } group = 'com.knf.demo' version = '0.0.1-SNAPSHOT' sourceCompatibility = '11' repositories { mavenCentral() } dependencies { implementation 'org.springframework.boot:spring-boot-starter-webflux' testImplementation 'org.springframework.boot:spring-boot-starter-test' testImplementation 'io.projectreactor:reactor-test' } test { useJUnitPlatform() } Service (VideoStreamingService.java) package  com.knf.demo.service ; import org.springframework.beans.factory.annotation. Autowired ; import org.springframew
Read more

Learn Java 8 streams with an example - print odd/even numbers from Array and List

Example 1: Java 8 program to print odd numbers from a List import java.util.Arrays; import java.util.List; import java.util.stream.Collectors; /*Java 8 Program to find Odd Numbers from a List*/ public class DriverClass { public static void main( String [] args) { List < Integer > numbers = Arrays. asList( 1 , 4 , 8 , 40 , 11 , 22 , 33 , 99 ); List < Integer > oddNumbers = numbers.stream(). filter(o -> o % 2 != 0 ). collect(Collectors.toList()); System.out.println(oddNumbers); } } Example 2: Java 8 program to print even numbers from a List import java.util.Arrays; import java.util.List; import java.util.stream.Collectors; /*Java 8 Program to find Even Numbers from a List*/ public class DriverClass { public static void main( String [] args) { List < Integer > numbers = Arrays.
Read more

Spring Boot + Mockito simple application with 100% code coverage

Image
In this article, we will show you a simple  Spring Boot example to demonstrate test methods for Controllers, Service, and Repository, And code coverage analysis using the EclEmma plugin. Technologies used: Spring Boot 2.6.4 Mockito 3.11.2 Maven 3+ EclEmma plugin Junit 5 Java 17 A quick overview of  Spring Boot, Mockito, and EclEmma plugin Spring boot: Spring boot to develop REST web services and microservices. Spring Boot has taken the Spring framework to the next level. It has drastically reduced the configuration and setup time required for spring projects. We can set up a project with almost zero configuration and start building the things that actually matter to your application. Mockito: Mockito is a mocking framework, a JAVA-predicated library that is utilized for efficacious unit testing of JAVA applications. Mockito is utilized to mock interfaces so that a dummy functionality can be integrated into a mock interface that can be utilized in unit testing. EclEmma : E
Read more

Spring Boot + OpenCSV Export Data to CSV Example

Image
Hello everyone, today we will learn how to export and download the data as a CSV file in a Spring Boot project. CSV stands for Comma-Separated-Values and it's a common format for doing a bulk data transfer between systems. For creating and parsing CSV files, we will use OpenCSV 3rd-party library. Technologies used  Spring Boot OpenCSV Spring Data JPA H2DB Maven Project directory Maven[pom.xml] A Project Object Model or POM is the fundamental unit of work in Maven. It is an XML file that contains information about the project and configuration details utilized by Maven to build the project. It contains default values for most projects. Some of the configurations that can be designated in the POM is the project dependencies, the plugins or goals that can be executed, the build profiles, and so on. Other information such as the project version, description, developers, mailing lists, and such can withal be designated. <?xml version = "1.0" encoding = "UTF-8"
Read more

Custom Exception Handling in Quarkus REST API

Image
Hello everyone, In this article, we will learn how to handle exceptions in the Quarkus REST application using ExceptionMapper interface implementations. ExceptionMapper is a contract for a provider that will map a thrown application exception to a Response object. More related topics, Quarkus + Angular 10 + MongoDB CRUD Example Quarkus + React JS + MongoDB CRUD Example Quarkus + Vue.js + MongoDB CRUD Example Build Reactive CRUD APIs With Quarkus, MongoDB, and Panache We will show you custom exception handling with the help of a simple application, Project Directory: application.properties knowledgefactory.custom.error.msg.usernotfound = User not found knowledgefactory.custom.error.msg.badrequest.numeric = User Id must be numeric Create Error Message: package org.knf.dev.demo.exception; public class ErrorMessage { private String message; private Boolean status; public String getMessage() { return message; } public void setMessage( String message)
Read more

DataTable-Pagination example with Spring boot, jQuery and ajax

Image
Hello everyone, Today we will show you the DataTable-Pagination example with Spring boot, jQuery, and ajax. The link to download the source code is provided at the end of this tutorial. More practice: Spring Boot - Spring Security -Google OAuth2 Login - Example Registration and Login with Spring Boot + Spring Security + Thymeleaf Spring Boot-Authentication and Authorization with Spring Security & JWT Kotlin - Spring Security -Google OAuth2 Login - Example Following technologies stack being used: Spring Boot 2.5.5 Java 11 Maven 3 Datatable jQuery javascript ajax Project Structure: pom.xml POM stands for project object model. It's the fundamental unit of work in Maven. It is an XML file that contains information about the project and configuration details used to build the project. It downloads required libraries easily using POM XML tags. <?xml version = "1.0" encoding = "UTF-8" ?> <project xmlns = "http://maven.a
Read more

Registration and Login with Spring Boot + Spring Security + Thymeleaf

Image
Hello everyone, I hope you all are well, today we will learn how to create user registration and login using Spring boot,  Spring security,  Thymeleaf, JPA, and H2DB. GitHub repository link is provided at the end of this tutorial. You can download the source code. Technologies used: Spring Boot  makes developing the web applications and microservices with Spring Framework faster and easier through three core capabilities: 1.  Autoconfiguration 2. An opinionated approach to configuration 3. The ability to create standalone applications Spring Security  is a Java/Java EE framework that provides authentication, authorization, and other security features for enterprise applications. Thymeleaf is a modern server-side Java template engine for both web and standalone environments. Maven  is a build automation tool used primarily for Java projects. Maven can also be used to build and manage projects written in C#, Ruby, Scala, and other languages. Java 11  is a major feature release of JAVA p
Read more

Node JS mini projects with source code - free download

Image
Project 1: User Management Application - Using Node JS, Angular 10 and MongoDB Technologies used: Node JS Angular 10 MongoDB Express For more information and   download   source code please   click here Project 2: User Management Application - Using Node JS, Vue.js, and MongoDB Technologies used: Node JS Vue.js MongoDB Express For more information and  download   source code please   click here Project 3: User Management Application - Node JS, React JS, and MongoDB Technologies used: Node JS React JS MongoDB Express For more information and   download   source code please   click here Project 4: Node JS: Authentication and Authorization with JWT in Express.js What is JSON Web Token? JSON Web Tokens (JWT) have been introduced as a self-contained way for securely transmitting information between parties as a JSON object.JSON Web Token (JWT) is an open standard (RFC 7519) that defines a compact. This information can be verified and trusted because it is digitally signed. JWTs can be signe
Read more

Spring boot web project free download:User Registration System

Image
Greetings from the Knowledgefactory team!!! We provide student projects, mini-projects, MVP products etc... absolutely free. Maybe you can build more on top of this project and produce your own product, that's all about you. Here we provided some links to download spring boot user registration system mini-projects. You can download the project for free. 1. User Registration system - Spring boot + Thymeleaf Objective Of Spring Boot On User Management System The main objective of this project is to manage the details of the user. Admin will manage all these activities. Functionalities Admin Login and Logout with Spring security Admin has permission to add new users, update users, view users, delete users. Technologies Used JDK 17  Spring Boot Thymeleaf Spring Security Spring MVC H2DB Maven More info and download source code - click here 2. User Registration system - Spring boot + MongoDB + Angular Objective Of Spring Boot On User Management System The main objective of this project i
Read more

Java - Blowfish Encryption and decryption Example

Image
Blowfish is a symmetric-key block cipher, designed in 1993 by Bruce Schneier and included in many cipher suites and encryption products. Blowfish provides a good encryption rate in software and no effective cryptanalysis of it has been found to date. However, the Advanced Encryption Standard (AES) now receives more attention, and Schneier recommends Twofish for modern applications. Example 1: Encryption and decryption using Blowfish import java.io.UnsupportedEncodingException; import java.nio.charset.Charset; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import java.util.Base64; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import javax.crypto.NoSuchPaddingException; import javax.crypto.spec.SecretKeySpec; /** * This program demonstrates how to encrypt/decrypt * input using the Blowfish * Cipher with the Java Cryptography. */ public class BlowfishDemo { p
Read more