Download file with resume

Arvados-DCO-1.1-Signed-off-by: Jakub Szlenk jakubszlenk@gmail.com

diff --git a/sdk/java-v2/src/main/java/org/arvados/client/api/client/KeepWebApiClient.java b/sdk/java-v2/src/main/java/org/arvados/client/api/client/KeepWebApiClient.java
index 2c3168649ff70b734eccb57b627a83967f3cf94e..2595956074edb3f8ddf280b38d90f4faeb07873e 100644 (file)
--- a/sdk/java-v2/src/main/java/org/arvados/client/api/client/KeepWebApiClient.java
+++ b/sdk/java-v2/src/main/java/org/arvados/client/api/client/KeepWebApiClient.java
@@ -10,9 +10,13 @@ package org.arvados.client.api.client;
 import okhttp3.HttpUrl;
 import okhttp3.Request;
 import okhttp3.RequestBody;
+import okhttp3.Response;
+import okhttp3.ResponseBody;
+
 import org.arvados.client.config.ConfigProvider;
 
 import java.io.File;
+import java.io.IOException;
 import java.io.InputStream;
 
 public class KeepWebApiClient extends BaseApiClient {
@@ -30,6 +34,26 @@ public class KeepWebApiClient extends BaseApiClient {
         return newFileCall(request);
     }
 
+    public byte[] downloadPartial(String collectionUuid, String filePathName, long offset) throws IOException {
+        Request.Builder builder = this.getRequestBuilder();
+        if (offset > 0) {
+            builder.addHeader("Range", "bytes=" + offset + "-");
+        }
+        Request request = builder.url(this.getUrlBuilder(collectionUuid, filePathName).build()).get().build();
+        try (Response response = client.newCall(request).execute()) {
+            if (!response.isSuccessful()) {
+                throw new IOException("Failed to download file: " + response);
+            }
+            try (ResponseBody body = response.body()) {
+                if (body != null) {
+                    return body.bytes();
+                } else {
+                    throw new IOException("Response body is null for request: " + request);
+                }
+            }
+        }
+    }
+
     public String delete(String collectionUuid, String filePathName) {
         Request request = getRequestBuilder()
                 .url(getUrlBuilder(collectionUuid, filePathName).build())

diff --git a/sdk/java-v2/src/main/java/org/arvados/client/logic/keep/FileDownloader.java b/sdk/java-v2/src/main/java/org/arvados/client/logic/keep/FileDownloader.java
index c1e8849e39f625128133bea1d8376e01e005ca54..3fe4e6433a2d357df3a55335fd5082d229e02b7d 100644 (file)
--- a/sdk/java-v2/src/main/java/org/arvados/client/logic/keep/FileDownloader.java
+++ b/sdk/java-v2/src/main/java/org/arvados/client/logic/keep/FileDownloader.java
@@ -20,9 +20,12 @@ import org.arvados.client.logic.keep.exception.DownloadFolderAlreadyExistsExcept
 import org.arvados.client.logic.keep.exception.FileAlreadyExistsException;
 import org.slf4j.Logger;
 
+import java.io.ByteArrayInputStream;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.RandomAccessFile;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.CompletableFuture;
@@ -70,6 +73,34 @@ public class FileDownloader {
         return downloadedFile;
     }
 
+    public File downloadFileWithResume(String collectionUuid, String fileName, String pathToDownloadFolder, long offset, int bufferSize) throws IOException {
+        if (bufferSize <= 0) {
+            throw new IllegalArgumentException("Buffer size must be greater than 0");
+        }
+
+        File destinationFile = new File(pathToDownloadFolder, fileName);
+
+        if (!destinationFile.exists()) {
+            boolean isCreated = destinationFile.createNewFile();
+            if (!isCreated) {
+                throw new IOException("Failed to create new file: " + destinationFile.getAbsolutePath());
+            }
+        }
+
+        try (RandomAccessFile outputFile = new RandomAccessFile(destinationFile, "rw")) {
+            outputFile.seek(offset);
+
+            byte[] buffer = new byte[bufferSize];
+            int bytesRead;
+            InputStream inputStream = new ByteArrayInputStream(keepWebApiClient.downloadPartial(collectionUuid, fileName, offset));
+            while ((bytesRead = inputStream.read(buffer)) != -1) {
+                outputFile.write(buffer, 0, bytesRead);
+            }
+        }
+
+        return destinationFile;
+    }
+
     public List<File> downloadFilesFromCollectionUsingKeepWeb(String collectionUuid, String pathToDownloadFolder) {
         String collectionTargetDir = setTargetDirectory(collectionUuid, pathToDownloadFolder).getAbsolutePath();
         List<FileToken> fileTokens = listFileInfoFromCollection(collectionUuid);

diff --git a/sdk/java-v2/src/test/java/org/arvados/client/api/client/KeepWebApiClientTest.java b/sdk/java-v2/src/test/java/org/arvados/client/api/client/KeepWebApiClientTest.java
index 07b7b2533991a1a32e3c0b7a5c6587b9ed07dec2..e796c690321c846060ceccbd4278d986516c70d1 100644 (file)
--- a/sdk/java-v2/src/test/java/org/arvados/client/api/client/KeepWebApiClientTest.java
+++ b/sdk/java-v2/src/test/java/org/arvados/client/api/client/KeepWebApiClientTest.java
@@ -13,12 +13,17 @@ import org.junit.Test;
 import java.io.File;
 import java.nio.file.Files;
 
+import okhttp3.mockwebserver.MockResponse;
+import okio.Buffer;
+
 import static org.arvados.client.test.utils.ApiClientTestUtils.getResponse;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 
 public class KeepWebApiClientTest extends ArvadosClientMockedWebServerTest {
 
-    private KeepWebApiClient client = new KeepWebApiClient(CONFIG);
+    private final KeepWebApiClient client = new KeepWebApiClient(CONFIG);
 
     @Test
     public void uploadFile() throws Exception {
@@ -36,4 +41,25 @@ public class KeepWebApiClientTest extends ArvadosClientMockedWebServerTest {
         assertThat(uploadResponse).isEqualTo("Created");
     }
 
+    @Test
+    public void downloadPartialIsPerformedSuccessfully() throws Exception {
+        // given
+        String collectionUuid = "some-collection-uuid";
+        String filePathName = "sample-file-path";
+        long offset = 1024;
+
+        byte[] expectedData = "test data".getBytes();
+
+        try (Buffer buffer = new Buffer().write(expectedData)) {
+            server.enqueue(new MockResponse().setBody(buffer));
+
+            // when
+            byte[] actualData = client.downloadPartial(collectionUuid, filePathName, offset);
+
+            // then
+            assertNotNull(actualData);
+            assertEquals(new String(expectedData), new String(actualData));
+        }
+    }
+
 }