1

我在 Dropwizard 中实现了一个文件上传 REST 端点。我对此很陌生，只是想学习。

@Path("/files")
@Produces(MediaType.APPLICATION_JSON)
public class FileUploadResource {

    private final MyAppWebConfiguration configuration;
    private static final Logger logger = LoggerFactory.getLogger(FileUploadResource.class);

    public FileUploadResource(MyAppWebConfiguration configuration) {
        this.configuration = configuration;
    }

    @POST
    @Consumes(MediaType.MULTIPART_FORM_DATA)
    public Response uploadFile(
            @FormDataParam("file") InputStream uploadedInputStream,
            @FormDataParam("file") FormDataContentDisposition fileDetail) throws IOException {

        logger.info("Request to upload the file ", fileDetail.getFileName());
        final String uploadedFileLocation = configuration.getCsvUploadPath();
        final String fileName = fileDetail.getFileName();
        writeToFile(uploadedInputStream, uploadedFileLocation, fileName);
        return Response.ok("File " + fileName + " is uploaded to the location " + uploadedFileLocation).build();
    }

    // save uploaded file to new location
    protected void writeToFile(InputStream uploadedInputStream, String uploadedFileLocation, String fileName) throws IOException {
        logger.info("Writing {} to {}", fileName, uploadedFileLocation);
        final java.nio.file.Path outputPath = FileSystems.getDefault().getPath(uploadedFileLocation, fileName);
        Files.copy(uploadedInputStream, outputPath, StandardCopyOption.REPLACE_EXISTING);
        logger.info("Uploaded {} to the location {}", fileName, uploadedFileLocation);
    }

该代码工作正常，并且能够上传文件。我正在尝试使用以下基于https://gist.github.com/psamsotha/218c6bbeb6164bac7cbc的代码对其进行测试：

public class FileUploadResourceTest extends JerseyTest {

    private final static MyAppWebConfiguration mockConfiguration = mock(MyAppWebConfiguration.class);

    @Override
    public ResourceConfig configure() {
        return new ResourceConfig(FileUploadResource.class)
                .register(MultiPartFeature.class)
                .register(new LoggingFilter(Logger.getAnonymousLogger(), true));
    }

    @Override
    public void configureClient(ClientConfig config) {
        config.register(MultiPartFeature.class);
    }

    @Test
    public void test() {
        FileDataBodyPart filePart = new FileDataBodyPart("file", new File("/Users/rocky/Downloads/test.csv"));
        filePart.setContentDisposition(FormDataContentDisposition.name("file").fileName("/Users/rocky/Downloads/test.csv").build());

        MultiPart multiPart = new FormDataMultiPart()
                .bodyPart(filePart);
        Response response = target("/files").request()
                .post(Entity.entity(multiPart, MediaType.MULTIPART_FORM_DATA_TYPE));
        assertThat(response.getStatus()).isEqualTo(Response.Status.OK.getStatusCode());
        response.close();
    }

此测试失败并出现以下错误：

WARNING: The following warnings have been detected: WARNING: HK2 service reification failed for [com.my.app.resources.FileUploadResource] with an exception:
MultiException stack 1 of 2
java.lang.NoSuchMethodException: Could not find a suitable constructor in com.my.app.resources.FileUploadResource class.
    at org.glassfish.jersey.internal.inject.JerseyClassAnalyzer.getConstructor(JerseyClassAnalyzer.java:192)
    at org.jvnet.hk2.internal.Utilities.getConstructor(Utilities.java:178)
    at org.jvnet.hk2.internal.ClazzCreator.initialize(ClazzCreator.java:128)
    at org.jvnet.hk2.internal.ClazzCreator.initialize(ClazzCreator.java:179)

我没有无参数构造函数，FileUploadResource但new ResourceConfig(FileUploadResource.class)需要一个无参数构造函数。如何在此处传递有关单参数构造函数的信息？

这里的任何帮助将不胜感激。此外，请随时提出有关代码和测试的任何其他最佳实践，以便我改进它们。

提前谢谢了。

4

1 回答 1

2

当您将资源注册为类时

new ResourceConfig(FileUploadResource.class)

您是在告诉泽西岛创建它。但它不知道如何创建它，因为只有一个接受配置对象的构造函数，Jersey 对此一无所知。相反，您应该只注册为一个对象。就像您在 Dropwizard ( env.jersey().register(...)) 上注册一样。

new ResourceConfig().regster(new FileUploadResource(mockConfiguration))
    ...

顺便说一句，使用 Dropwizard，我们不需要显式使用JerseyTest. Dropwizard 带有一个 JUnit 规则，它明确运行自己的规则，JerseyTest我们可以使用规则对其进行配置。请参阅这个问题，我在其中发布了一个完整的示例。

于 2016-04-07T23:24:43.207 回答