Bael 5481 java httpclient post (#12118)

* BAEL-5481: Create new module

* BAEL-5481: Sync and async example

* BAEL-5481: Concurrent example

* BAEL-5481: Concurrent example

* BAEL-5481: JSON body example

* BAEL-5481: Form data example

* BAEL-5481: File upload example

* BAEL-5481: PR comments + Jenkins

* BAEL-5481: Update aftifact ID

* BAEL-5481: Spaces

core-java-modules/core-java-httpclient/src/test/java/com/baeldung/httpclient/HttpClientPostUnitTest.java

@@ -0,0 +1,99 @@
+package com.baeldung.httpclient;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+import java.io.IOException;
+import java.net.http.HttpResponse;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.stream.Collectors;
+
+import static org.assertj.core.api.Assertions.*;
+
+class HttpClientPostUnitTest extends PostRequestMockServer {
+
+    @Test
+    void givenSyncPostRequest_whenServerIsAvailable_thenOkStatusIsReceived() throws IOException, InterruptedException {
+        HttpResponse<String> response = HttpClientPost.sendSynchronousPost(serviceUrl);
+        assertThat(response.statusCode()).isEqualTo(200);
+        assertThat(response.body()).isEqualTo("{\"message\":\"ok\"}");
+    }
+
+    @Test
+    void givenAsyncPostRequest_whenServerIsAvailable_thenOkStatusIsReceived() throws ExecutionException, InterruptedException {
+        CompletableFuture<HttpResponse<String>> futureResponse = HttpClientPost.sendAsynchronousPost(serviceUrl);
+        HttpResponse<String> response = futureResponse.get();
+
+        assertThat(response.statusCode()).isEqualTo(200);
+        assertThat(response.body()).isEqualTo("{\"message\":\"ok\"}");
+    }
+
+    @Test
+    void givenConcurrentPostRequests_whenServerIsAvailable_thenOkStatusIsReceived() throws ExecutionException, InterruptedException {
+        List<CompletableFuture<HttpResponse<String>>> completableFutures = HttpClientPost
+          .sendConcurrentPost(List.of(serviceUrl, serviceUrl));
+
+        CompletableFuture<List<HttpResponse<String>>> combinedFutures = CompletableFuture
+          .allOf(completableFutures.toArray(new CompletableFuture[0]))
+          .thenApply(future ->
+            completableFutures.stream()
+              .map(CompletableFuture::join)
+              .collect(Collectors.toList()));
+
+        List<HttpResponse<String>> responses = combinedFutures.get();
+        responses.forEach((response) -> {
+            assertThat(response.statusCode()).isEqualTo(200);
+            assertThat(response.body()).isEqualTo("{\"message\":\"ok\"}");
+        });
+    }
+
+    @Test
+    void givenPostRequestWithAuthClient_whenServerIsAvailable_thenOkStatusIsReceived() throws IOException, InterruptedException {
+        HttpResponse<String> response = HttpClientPost.sendPostWithAuthClient(serviceUrl);
+
+        assertThat(response.statusCode()).isEqualTo(200);
+        assertThat(response.body()).isEqualTo("{\"message\":\"ok\"}");
+    }
+
+    @Test
+    void givenPostRequestWithAuthHeader_whenServerIsAvailable_thenOkStatusIsReceived() throws IOException, InterruptedException {
+        HttpResponse<String> response = HttpClientPost.sendPostWithAuthHeader(serviceUrl);
+
+        assertThat(response.statusCode()).isEqualTo(200);
+        assertThat(response.body()).isEqualTo("{\"message\":\"ok\"}");
+    }
+
+    @Test
+    void givenPostRequestWithJsonBody_whenServerIsAvailable_thenOkStatusIsReceived() throws IOException, InterruptedException {
+        HttpResponse<String> response = HttpClientPost.sendPostWithJsonBody(serviceUrl);
+
+        assertThat(response.statusCode()).isEqualTo(200);
+        assertThat(response.body()).isEqualTo("{\"message\":\"ok\"}");
+    }
+
+    @Test
+    void givenPostRequestWithFormData_whenServerIsAvailable_thenOkStatusIsReceived() throws IOException, InterruptedException {
+        HttpResponse<String> response = HttpClientPost.sendPostWithFormData(serviceUrl);
+
+        assertThat(response.statusCode()).isEqualTo(200);
+        assertThat(response.body()).isEqualTo("{\"message\":\"ok\"}");
+    }
+
+    @Test
+    void givenPostRequestWithFileData_whenServerIsAvailable_thenOkStatusIsReceived(@TempDir Path tempDir) throws IOException, InterruptedException {
+        Path file = tempDir.resolve("temp.txt");
+        List<String> lines = Arrays.asList("1", "2", "3");
+        Files.write(file, lines);
+
+        HttpResponse<String> response = HttpClientPost.sendPostWithFileData(serviceUrl, file);
+
+        assertThat(response.statusCode()).isEqualTo(200);
+        assertThat(response.body()).isEqualTo("{\"message\":\"ok\"}");
+    }
+
+}

core-java-modules/core-java-httpclient/src/test/java/com/baeldung/httpclient/PostRequestMockServer.java

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+package com.baeldung.httpclient;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.mockserver.client.MockServerClient;
+import org.mockserver.integration.ClientAndServer;
+import org.mockserver.model.HttpStatusCode;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.URISyntaxException;
+
+import static org.mockserver.integration.ClientAndServer.startClientAndServer;
+import static org.mockserver.model.HttpRequest.request;
+import static org.mockserver.model.HttpResponse.response;
+
+public abstract class PostRequestMockServer {
+
+    public static ClientAndServer mockServer;
+    public static String serviceUrl;
+
+    private static int serverPort;
+
+    public static final String SERVER_ADDRESS = "127.0.0.1";
+    public static final String PATH = "/test1";
+    public static final String METHOD = "POST";
+
+    @BeforeAll
+    static void startServer() throws IOException, URISyntaxException {
+        serverPort = getFreePort();
+        serviceUrl = "http://" + SERVER_ADDRESS + ":" + serverPort + PATH;
+        mockServer = startClientAndServer(serverPort);
+        mockBasicPostRequest();
+    }
+
+    @AfterAll
+    static void stopServer() {
+        mockServer.stop();
+    }
+
+    private static void mockBasicPostRequest() {
+        new MockServerClient(SERVER_ADDRESS, serverPort)
+          .when(
+            request()
+              .withPath(PATH)
+              .withMethod(METHOD)
+          )
+          .respond(
+            response()
+              .withStatusCode(HttpStatusCode.OK_200.code())
+              .withBody("{\"message\":\"ok\"}")
+          );
+    }
+
+    private static int getFreePort () throws IOException {
+        try (ServerSocket serverSocket = new ServerSocket(0)) {
+            return serverSocket.getLocalPort();
+        }
+    }
+
+}