How to call REST API Using Spring Webflux WebClient set proxy with authorization while calling the external site and Generate base 64 authentication header spring boot

This post will explain us, how can we call REST API using Webclient. How to set Proxy username and password to call the external site. Step 1: Add folllowing dependency in your pom.xml

   
	 org.springframework.boot
	 spring-boot-starter-webflux
	

Step 2:

import lombok.extern.slf4j.XSlf4j;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.http.client.reactive.ClientHttpConnector;
import org.springframework.http.client.reactive.ReactorClientHttpConnector;
import org.springframework.web.reactive.function.client.WebClient;
import reactor.netty.http.client.HttpClient;
import reactor.netty.transport.ProxyProvider;

import java.net.URI;
import java.util.Base64;
import java.util.function.Consumer;
import java.util.function.Function;
 public static void main(String[] args) {
  try {
  //Generate HttP client to set proxy details
  HttpClient httpClient = HttpClient.create()
            .proxy(proxy-> proxy.type(ProxyProvider.Proxy.HTTP)
            .host("javaguruonline.com").port(1328)
            .username("siva")
            .password(new Function() {
                        @Override
                        public String apply(String s) {
                            return "test@12!";
                        }
                    }));
  ClientHttpConnector clientHttpConnector = 
           new ReactorClientHttpConnector(httpClient);
  WebClient webClient = WebClient.builder().build();
  String plainCredentials = "username" + ":" + "password";
  String base64Credentials = new String(Base64.getEncoder()
                           .encode(plainCredentials.getBytes()));
  String authorizationHeader = "Basic " + base64Credentials;
  //input json
  String json = "{\n" +
                    "  \"user\": \"siva\"\n" +
                    "}";
            //set http headers
  Consumer httpHeaders = new Consumer() {
     @Override
     public void accept(HttpHeaders httpHeaders) {
       httpHeaders.add("Authorization", authorizationHeader);
       httpHeaders.add("Content-Type", "application/json");
       httpHeaders.add("Proxy-Authorization", authorizationHeader);
     }};
   //post call to external URL and get ResponseEntity as response like body 
   //and http status code etc..
    ResponseEntity result = webClient.mutate()
                    .clientConnector(clientHttpConnector)
                    .build()
                    .post()
                    .uri(new URI("https://localhost:8080/test/details"))
                    .bodyValue(json)
                    .accept(MediaType.APPLICATION_JSON)
                    .retrieve()
                    .toEntity(String.class)
                    .block();
            System.out.println(result);
        }
        catch(Exception ex){
        }

Hope this post will help some one, while working on the REST API calls