Multipart examples update (helidon-io#2830)

* add microprofile multipart example

* Update SE multipart example to add a unit test that uses WebClient.
Add an example under microprofile that implements the same application using Jersey.

* rethrow IOException using UncheckedIOException

examples/media/multipart/README.md

@@ -0,0 +1,23 @@
+# Helidon SE MultiPart Example
+
+This example demonstrates how to use `MultiPartSupport` with both the `WebServer`
+ and `WebClient` APIs.
+
+This project implements a simple file service web application that supports uploading
+and downloading files. The unit test uses the `WebClient` API to test the endpoints.
+
+## Build
+
+```
+mvn package
+```
+
+## Run
+
+First, start the server:
+
+```
+java -jar target/helidon-examples-microprofile-multipart.jar
+```
+
+Then open <http://localhost:8080/ui> in your browser.

examples/media/multipart/pom.xml

@@ -60,6 +60,21 @@
             <groupId>org.glassfish</groupId>
             <artifactId>jakarta.json</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.hamcrest</groupId>
+            <artifactId>hamcrest-all</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>io.helidon.webclient</groupId>
+            <artifactId>helidon-webclient</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>

examples/media/multipart/src/main/java/io/helidon/examples/media/multipart/FileService.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2021 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.
@@ -16,13 +16,13 @@
 package io.helidon.examples.media.multipart;
 
 import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.ByteChannel;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.StandardOpenOption;
 import java.util.Map;
-import java.util.stream.Stream;
 
 import javax.json.Json;
 import javax.json.JsonArrayBuilder;
@@ -31,7 +31,6 @@
 import io.helidon.common.http.DataChunk;
 import io.helidon.common.http.Http;
 import io.helidon.common.http.MediaType;
-import io.helidon.common.reactive.Multi;
 import io.helidon.media.multipart.ContentDisposition;
 import io.helidon.media.multipart.ReadableBodyPart;
 import io.helidon.media.multipart.ReadableMultiPart;
@@ -41,24 +40,19 @@
 import io.helidon.webserver.ServerResponse;
 import io.helidon.webserver.Service;
 
-import static io.helidon.common.http.Http.Status.BAD_REQUEST_400;
-import static io.helidon.common.http.Http.Status.NOT_FOUND_404;
-
 /**
  * File service.
  */
 public final class FileService implements Service {
 
-    private final JsonBuilderFactory jsonFactory;
-    private final Path storage;
+    private static final JsonBuilderFactory JSON_FACTORY = Json.createBuilderFactory(Map.of());
+    private final FileStorage storage;
 
     /**
      * Create a new file upload service instance.
      */
     FileService() {
-        jsonFactory = Json.createBuilderFactory(Map.of());
-        storage = createStorage();
-        System.out.println("Storage: " + storage);
+        storage = new FileStorage();
     }
 
     @Override
@@ -69,25 +63,13 @@ public void update(Routing.Rules rules) {
     }
 
     private void list(ServerRequest req, ServerResponse res) {
-        JsonArrayBuilder arrayBuilder = jsonFactory.createArrayBuilder();
-        listFiles(storage).forEach(arrayBuilder::add);
-        res.send(jsonFactory.createObjectBuilder().add("files", arrayBuilder).build());
+        JsonArrayBuilder arrayBuilder = JSON_FACTORY.createArrayBuilder();
+        storage.listFiles().forEach(arrayBuilder::add);
+        res.send(JSON_FACTORY.createObjectBuilder().add("files", arrayBuilder).build());
     }
 
     private void download(ServerRequest req, ServerResponse res) {
-        Path filePath = storage.resolve(req.path().param("fname"));
-        if (!filePath.getParent().equals(storage)) {
-            res.status(BAD_REQUEST_400).send("Invalid file name");
-            return;
-        }
-        if (!Files.exists(filePath)) {
-            res.status(NOT_FOUND_404).send();
-            return;
-        }
-        if (!Files.isRegularFile(filePath)) {
-            res.status(BAD_REQUEST_400).send("Not a file");
-            return;
-        }
+        Path filePath = storage.lookup(req.path().param("fname"));
         ResponseHeaders headers = res.headers();
         headers.contentType(MediaType.APPLICATION_OCTET_STREAM);
         headers.put(Http.Header.CONTENT_DISPOSITION, ContentDisposition.builder()
@@ -108,7 +90,7 @@ private void upload(ServerRequest req, ServerResponse res) {
     private void bufferedUpload(ServerRequest req, ServerResponse res) {
         req.content().as(ReadableMultiPart.class).thenAccept(multiPart -> {
             for (ReadableBodyPart part : multiPart.fields("file[]")) {
-                writeBytes(storage, part.filename(), part.as(byte[].class));
+                writeBytes(storage.create(part.filename()), part.as(byte[].class));
             }
             res.status(Http.Status.MOVED_PERMANENTLY_301);
             res.headers().put(Http.Header.LOCATION, "/ui");
@@ -125,41 +107,22 @@ private void streamUpload(ServerRequest req, ServerResponse res) {
                     res.send();
                 }).forEach((part) -> {
                     if ("file[]".equals(part.name())) {
-                        final ByteChannel channel = newByteChannel(storage, part.filename());
-                        Multi.create(part.content())
+                        final ByteChannel channel = newByteChannel(storage.create(part.filename()));
+                        part.content()
                                 .forEach(chunk -> writeChunk(channel, chunk))
                                 .thenAccept(it -> closeChannel(channel));
                     }
                 });
     }
 
-    private static Path createStorage() {
-        try {
-            return Files.createTempDirectory("fileupload");
-        } catch (IOException ex) {
-            throw new RuntimeException(ex);
-        }
-    }
-
-    private static Stream<String> listFiles(Path storage) {
-        try {
-            return Files.walk(storage)
-                    .filter(Files::isRegularFile)
-                    .map(storage::relativize)
-                    .map(Path::toString);
-        } catch (IOException ex) {
-            throw new RuntimeException(ex);
-        }
-    }
-
-    private static void writeBytes(Path storage, String fname, byte[] bytes) {
+    private static void writeBytes(Path file, byte[] bytes) {
         try {
-            Files.write(storage.resolve(fname), bytes,
+            Files.write(file, bytes,
                     StandardOpenOption.CREATE,
                     StandardOpenOption.WRITE,
                     StandardOpenOption.TRUNCATE_EXISTING);
         } catch (IOException ex) {
-            throw new RuntimeException(ex);
+            throw new UncheckedIOException(ex);
         }
     }
 
@@ -169,7 +132,7 @@ private static void writeChunk(ByteChannel channel, DataChunk chunk) {
                 channel.write(byteBuffer);
             }
         } catch (IOException ex) {
-            throw new RuntimeException(ex);
+            throw new UncheckedIOException(ex);
         } finally {
             chunk.release();
         }
@@ -179,18 +142,18 @@ private void closeChannel(ByteChannel channel) {
         try {
             channel.close();
         } catch (IOException ex) {
-            throw new RuntimeException(ex);
+            throw new UncheckedIOException(ex);
         }
     }
 
-    private static ByteChannel newByteChannel(Path storage, String fname) {
+    private static ByteChannel newByteChannel(Path file) {
         try {
-            return Files.newByteChannel(storage.resolve(fname),
+            return Files.newByteChannel(file,
                     StandardOpenOption.CREATE,
                     StandardOpenOption.WRITE,
                     StandardOpenOption.TRUNCATE_EXISTING);
         } catch (IOException ex) {
-            throw new RuntimeException(ex);
+            throw new UncheckedIOException(ex);
         }
     }
 }

examples/media/multipart/src/main/java/io/helidon/examples/media/multipart/FileStorage.java

@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2021 Oracle and/or its affiliates. All rights reserved.
+ *
+ * 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.examples.media.multipart;
+
+import java.io.IOException;
+import java.io.UncheckedIOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.stream.Stream;
+
+import io.helidon.webserver.BadRequestException;
+import io.helidon.webserver.NotFoundException;
+
+/**
+ * Simple bean to managed a directory based storage.
+ */
+public class FileStorage {
+
+    private final Path storageDir;
+
+    /**
+     * Create a new instance.
+     */
+    public FileStorage() {
+        try {
+            storageDir = Files.createTempDirectory("fileupload");
+        } catch (IOException ex) {
+            throw new UncheckedIOException(ex);
+        }
+    }
+
+    /**
+     * Get the storage directory.
+     *
+     * @return directory
+     */
+    public Path storageDir() {
+        return storageDir;
+    }
+
+    /**
+     * Get the names of the files in the storage directory.
+     *
+     * @return Stream of file names
+     */
+    public Stream<String> listFiles() {
+        try {
+            return Files.walk(storageDir)
+                        .filter(Files::isRegularFile)
+                        .map(storageDir::relativize)
+                        .map(java.nio.file.Path::toString);
+        } catch (IOException ex) {
+            throw new UncheckedIOException(ex);
+        }
+    }
+
+    /**
+     * Create a new file in the storage.
+     *
+     * @param fname file name
+     * @return file
+     * @throws BadRequestException if the resolved file is not contained in the storage directory
+     */
+    public Path create(String fname) {
+        Path file = storageDir.resolve(fname);
+        if (!file.getParent().equals(storageDir)) {
+            throw new BadRequestException("Invalid file name");
+        }
+        return file;
+    }
+
+    /**
+     * Lookup an existing file in the storage.
+     *
+     * @param fname file name
+     * @return file
+     * @throws NotFoundException   If the resolved file does not exist
+     * @throws BadRequestException if the resolved file is not contained in the storage directory
+     */
+    public Path lookup(String fname) {
+        Path file = storageDir.resolve(fname);
+        if (!file.getParent().equals(storageDir)) {
+            throw new BadRequestException("Invalid file name");
+        }
+        if (!Files.exists(file)) {
+            throw new NotFoundException("file not found");
+        }
+        if (!Files.isRegularFile(file)) {
+            throw new BadRequestException("Not a file");
+        }
+        return file;
+    }
+}

examples/media/multipart/src/main/java/io/helidon/examples/media/multipart/Main.java

@@ -50,12 +50,18 @@ static Routing createRouting() {
     }
 
     /**
-     * Executes the example.
-     *
+     * Application main entry point.
      * @param args command line arguments.
      */
-    public static void main(String[] args) {
+    public static void main(final String[] args) {
+        startServer();
+    }
 
+    /**
+     * Start the server.
+     * @return the created {@link WebServer} instance
+     */
+    static WebServer startServer() {
         WebServer server = WebServer.builder(createRouting())
                 .port(8080)
                 .addMediaSupport(MultiPartSupport.create())
@@ -71,5 +77,8 @@ public static void main(String[] args) {
         server.whenShutdown()
                 .thenRun(() -> System.out.println("WEB server is DOWN. Good bye!"));
 
+        return server;
     }
+
+
 }