Upload Cucumber Reports with Gzip encoding (#3115)

Author: mpkorstanje

CHANGELOG.md

@@ -10,6 +10,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- [Core] Upload Cucumber Reports with Gzip encoding ([#3115](https://github.com/cucumber/cucumber-jvm/pull/3115))
 
 ## [7.32.0] - 2025-11-21
 ### Changed

cucumber-core/src/main/java/io/cucumber/core/plugin/UrlOutputStream.java

@@ -19,6 +19,7 @@
 import java.util.Map.Entry;
 import java.util.Optional;
 import java.util.stream.Collectors;
+import java.util.zip.GZIPOutputStream;
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 import static java.nio.file.Files.newOutputStream;
@@ -90,6 +91,7 @@ private Optional<String> sendRequest(Proxy proxy, URL url, HttpMethod method, bo
                 sendRequest(option.getProxy(), new URL(location), CurlOption.HttpMethod.PUT, false);
             }
         } else {
+            urlConnection.setRequestProperty("Content-Encoding", "gzip");
             urlConnection.setDoOutput(true);
             sendRequestBody(urlConnection, requestHeaders, temp);
             getResponseBody(urlConnection, requestHeaders);
@@ -108,7 +110,7 @@ private static HttpURLConnection openConnection(Proxy proxy, URL url, HttpMethod
     private static void sendRequestBody(
             HttpURLConnection urlConnection, Map<String, List<String>> requestHeaders, Path requestBody
     ) throws IOException {
-        try (OutputStream outputStream = urlConnection.getOutputStream()) {
+        try (OutputStream outputStream = new GZIPOutputStream(urlConnection.getOutputStream())) {
             Files.copy(requestBody, outputStream);
         } catch (IOException e) {
             String method = urlConnection.getRequestMethod();

cucumber-core/src/test/java/io/cucumber/core/plugin/UrlOutputStreamTest.java

@@ -14,13 +14,17 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.io.Writer;
 import java.net.ServerSocket;
+import java.nio.charset.StandardCharsets;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
+import java.util.zip.GZIPInputStream;
 
 import static java.lang.String.format;
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -100,7 +104,6 @@ void it_sends_the_body_once_for_202_and_location_with_get_without_token(Vertx ve
         if (exception != null) {
             throw exception;
         }
-        assertThat(testServer.receivedBody.toString("utf-8"), is(equalTo(requestBody)));
     }
 
     @Test
@@ -225,11 +228,10 @@ public void start(Promise<Void> startPromise) {
 
                     ctx.request().handler(receivedBody::appendBuffer);
                     ctx.request().endHandler(e -> {
-                        String receivedBodyString = receivedBody.toString("utf-8");
                         ctx.response().setChunked(true);
                         ctx.response().write(responseBody);
                         ctx.response().end();
-                        testContext.verify(() -> assertThat(receivedBodyString, is(equalTo(expectedBody))));
+                        testContext.verify(() -> assertThat(unzipBody(), is(equalTo(expectedBody))));
                     });
                 });
             });
@@ -239,6 +241,21 @@ public void start(Promise<Void> startPromise) {
                     .listen(port, e -> startPromise.complete());
         }
 
+        private String unzipBody() {
+            ByteArrayOutputStream out = new ByteArrayOutputStream();
+            ByteArrayInputStream compressedIn = new ByteArrayInputStream(receivedBody.getBytes());
+            byte[] buffer = new byte[4096];
+            try (GZIPInputStream uncompressedIn = new GZIPInputStream(compressedIn)) {
+                int read;
+                while ((read = uncompressedIn.read(buffer, 0, buffer.length)) != -1) {
+                    out.write(buffer, 0, read);
+                }
+            } catch (IOException ex) {
+                throw new IllegalStateException(ex);
+            }
+            return new String(out.toByteArray(), StandardCharsets.UTF_8);
+        }
+
     }
 
 }