4.x: Move WriteBufferTest to correct module (helidon-io#9276)

webserver/tests/webserver/src/test/java/io/helidon/webserver/tests/NoWriteBufferTest.java

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2024 Oracle and/or its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.helidon.webserver.tests;
+
+import io.helidon.http.Method;
+import io.helidon.http.Status;
+import io.helidon.webclient.api.HttpClientResponse;
+import io.helidon.webclient.http1.Http1Client;
+import io.helidon.webserver.WebServerConfig;
+import io.helidon.webserver.http.HttpRules;
+import io.helidon.webserver.http.ServerResponse;
+import io.helidon.webserver.testing.junit5.ServerTest;
+import io.helidon.webserver.testing.junit5.SetUpRoute;
+import io.helidon.webserver.testing.junit5.SetUpServer;
+import org.junit.jupiter.api.Test;
+
+import java.io.OutputStream;
+import java.nio.charset.StandardCharsets;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * Test that a simple response can be sent using the {@link ServerResponse#outputStream()} using no write buffer
+ * (i.e. the write buffer size was set to {@code 0}).
+ */
+@ServerTest
+class NoWriteBufferTest {
+    private static final String RESPONSE = "Hello World!";
+
+    private final Http1Client client;
+
+    NoWriteBufferTest(Http1Client client) {
+        this.client = client;
+    }
+
+    @SetUpServer
+    static void setup(WebServerConfig.Builder builder) {
+        builder.writeBufferSize(0);
+    }
+
+    @SetUpRoute
+    static void routing(HttpRules rules) {
+        rules.get("/", (req, res) -> {
+            try(OutputStream out = res.outputStream()) {
+                out.write(RESPONSE.getBytes(StandardCharsets.UTF_8));
+            }
+        });
+    }
+
+    @Test
+    void noWriteBufferTest() throws Exception {
+        try (HttpClientResponse response = client.method(Method.GET).request()) {
+            assertThat(response.status(), is(Status.OK_200));
+            assertThat(response.entity().as(String.class), is(RESPONSE));
+        }
+    }
+}