Merge pull request #10840 from iulian-manda/master

BAEL-4856 Download a binary file using OkHttp

libraries-http-2/src/test/java/com/baeldung/okhttp/download/BinaryFileDownloaderIntegrationTest.java

@@ -0,0 +1,39 @@
+package com.baeldung.okhttp.download;
+
+import okhttp3.OkHttpClient;
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.MockWebServer;
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.FileOutputStream;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+public class BinaryFileDownloaderIntegrationTest {
+
+    @Rule
+    public MockWebServer server = new MockWebServer();
+
+    @Test
+    public void givenATextFile_whenDownload_thenExpectFileDownloaded() {
+        String body = "Hello Baeldung Readers!";
+        server.enqueue(new MockResponse().setBody(body));
+        String fileName = "download.txt";
+
+        ProgressCallback progressCallback = progress -> assertEquals(100.0, progress, .0);
+        try (BinaryFileWriter writer = new BinaryFileWriter(new FileOutputStream(fileName), progressCallback); BinaryFileDownloader tested = new BinaryFileDownloader(new OkHttpClient(), writer)) {
+            long downloaded = tested.download(server.url("/greetings").toString());
+            assertEquals(body.length(), downloaded);
+            File downloadedFile = new File(fileName);
+            assertTrue(downloadedFile.isFile());
+            assertTrue(downloadedFile.delete());
+        } catch (Exception e) {
+            fail("An unexpected exception has occurred: " + e);
+        }
+    }
+
+}

libraries-http-2/src/test/java/com/baeldung/okhttp/download/BinaryFileDownloaderUnitTest.java

@@ -0,0 +1,74 @@
+package com.baeldung.okhttp.download;
+
+import okhttp3.Call;
+import okhttp3.MediaType;
+import okhttp3.OkHttpClient;
+import okhttp3.Protocol;
+import okhttp3.Request;
+import okhttp3.Response;
+import okhttp3.ResponseBody;
+import org.jetbrains.annotations.NotNull;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+import java.io.InputStream;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyDouble;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@RunWith(MockitoJUnitRunner.class)
+public class BinaryFileDownloaderUnitTest {
+
+    @Mock
+    private OkHttpClient client;
+    @Mock
+    private BinaryFileWriter writer;
+    @InjectMocks
+    private BinaryFileDownloader tested;
+
+    @Test
+    public void givenUrlAndResponse_whenDownload_thenExpectFileWritten() throws Exception {
+        String url = "http://example.com/file";
+        Call call = mock(Call.class);
+        when(client.newCall(any(Request.class))).thenReturn(call);
+        ResponseBody body = ResponseBody.create("BODY", MediaType.get("application/text"));
+        Response response = createResponse(url, body);
+        when(call.execute()).thenReturn(response);
+        when(writer.write(any(), anyDouble())).thenReturn(1L);
+
+        try (BinaryFileDownloader tested = new BinaryFileDownloader(client, writer)) {
+            long size = tested.download(url);
+            assertEquals(1L, size);
+            verify(writer).write(any(InputStream.class), anyDouble());
+        }
+        verify(writer).close();
+    }
+
+    @Test(expected = IllegalStateException.class)
+    public void givenUrlAndResponseWithNullBody_whenDownload_thenExpectIllegalStateException() throws Exception {
+        String url = "http://example.com/file";
+        Call call = mock(Call.class);
+        when(client.newCall(any(Request.class))).thenReturn(call);
+        Response response = createResponse(url, null);
+        when(call.execute()).thenReturn(response);
+
+        tested.download(url);
+
+        verify(writer, times(0)).write(any(InputStream.class), anyDouble());
+    }
+
+    @NotNull
+    private Response createResponse(String url, ResponseBody body) {
+        Request request = new Request.Builder().url(url).build();
+        return new Response.Builder().code(200).request(request).protocol(Protocol.HTTP_2).message("Message").body(body).build();
+    }
+
+}

libraries-http-2/src/test/java/com/baeldung/okhttp/download/BinaryFileWriterUnitTest.java

@@ -0,0 +1,55 @@
+package com.baeldung.okhttp.download;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@RunWith(MockitoJUnitRunner.class)
+public class BinaryFileWriterUnitTest {
+
+    @Mock
+    private OutputStream outputStream;
+
+    @Test
+    public void givenInputStream_whenWrite_thenExpectWritten() throws Exception {
+        InputStream inputStream = mock(InputStream.class);
+        when(inputStream.read(any(), anyInt(), anyInt())).thenReturn(10, -1);
+
+        try (BinaryFileWriter tested = new BinaryFileWriter(outputStream, progress -> assertEquals(100.0, progress, .0))) {
+            long result = tested.write(inputStream, 10);
+
+            assertEquals(10, result);
+            verify(outputStream).write(any(), eq(0), eq(10));
+            verify(inputStream).close();
+        }
+        verify(outputStream).close();
+    }
+
+    @Test
+    public void givenInputStreamEmpty_whenWrite_thenExpectNotWritten() throws Exception {
+        InputStream inputStream = mock(InputStream.class);
+
+        try (BinaryFileWriter tested = new BinaryFileWriter(outputStream, progress -> assertEquals(100.0, progress, .0))) {
+            long result = tested.write(inputStream, 1);
+
+            assertEquals(0, result);
+            verify(outputStream, times(0)).write(any(), anyInt(), anyInt());
+            verify(inputStream).close();
+        }
+        verify(outputStream).close();
+    }
+
+}