java - Jersey 多部分表单数据默认值？

Question

我有一个接受 Multipart Form Data 类型的方法。此方法的参数之一是 file表单数据参数，显示为

@FormDataParam("file") InputStream inputStream,
@FormDataParam("file") FormDataContentDisposition contentDispositionHeader

我希望有时能够在不提供表单数据参数 file 的情况下访问此端点，但是现在当我将其忽略时，该方法会立即返回 400 错误请求。有没有办法可以设置它以便我可以忽略它？或者有什么方法可以为此设置默认值(即为空？)。任何帮助，将不胜感激。我的方法声明如下:

@POST
@Path("/publish")
@Consumes(MediaType.MULTIPART_FORM_DATA)
public Response publish(@Auth Key key,
                        @QueryParam("email") String email,
                        @HeaderParam("password") String password,
                        @QueryParam("type") PublishType type,
                        @QueryParam("message") String message,
                        @FormDataParam("file") InputStream inputStream,
                        @FormDataParam("file") FormDataContentDisposition
                              contentDispositionHeader,
                        @FormDataParam("title") @DefaultValue("") String videoTitle) {
    // code here
}

最后，我想创建一个端点，用户可以在其中将文本发布到数据库，并可选择包含图像或某种类型的媒体。让我知道是否有另一种方法可以实现这一目标。

谢谢!

Answer 1

它不漂亮，但我唯一能想到的(如果你不想发布任何正文)就是使用 Jersey 的 ContainerRequest你可以注入(inject)到方法中。然后如果有任何 body ，得到多部分为FormDataMultiPart只需手动遍历零件。

@POST
@Produces(MediaType.TEXT_PLAIN)
@Consumes(MediaType.MULTIPART_FORM_DATA)
public String post(@Context ContainerRequest request) {
    final String contentLength = request.getHeaderString(HttpHeaders.CONTENT_LENGTH);
    if (contentLength != null && Integer.parseInt(contentLength) != 0) {
        FormDataMultiPart multiPart = request.readEntity(FormDataMultiPart.class);
        FormDataBodyPart part = multiPart.getField("test");
        String result = part.getValueAs(String.class);
        return result;
    }
    return "no body";
}

下面是一个完整的测试

import org.glassfish.jersey.client.ClientConfig;
import org.glassfish.jersey.filter.LoggingFilter;
import org.glassfish.jersey.media.multipart.*;
import org.glassfish.jersey.server.ContainerRequest;
import org.glassfish.jersey.server.ResourceConfig;
import org.glassfish.jersey.test.JerseyTest;
import org.junit.Test;

import javax.ws.rs.*;
import javax.ws.rs.client.Entity;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.HttpHeaders;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.ext.ExceptionMapper;
import java.util.logging.Logger;

import static org.junit.Assert.assertEquals;

/**
 * Example with default value for multipart field.
 *
 * Dependencies for JUnit test.
 *
 *   <dependency>
 *     <groupId>org.glassfish.jersey.test-framework.providers</groupId>
 *     <artifactId>jersey-test-framework-provider-grizzly2</artifactId>
 *     <scope>test</scope>
 *     <version>${jersey2.version}</version>
 *   </dependency>
 *   <dependency>
 *     <groupId>org.glassfish.jersey.media</groupId>
 *     <artifactId>jersey-media-multipart</artifactId>
 *     <version>${jersey2.version}</version>
 *  </dependency>
 */
public class MultiPartMissingTest extends JerseyTest {

    @Path("test")
    public static class TestResource {

        @POST
        @Produces(MediaType.TEXT_PLAIN)
        @Consumes(MediaType.MULTIPART_FORM_DATA)
        public String post(@Context ContainerRequest request) {
            final String contentLength = request.getHeaderString(HttpHeaders.CONTENT_LENGTH);
            if (contentLength != null && Integer.parseInt(contentLength) != 0) {
                FormDataMultiPart multiPart = request.readEntity(FormDataMultiPart.class);
                FormDataBodyPart part = multiPart.getField("test");
                String result = part.getValueAs(String.class);
                return result;
            }
            return "no body";
        }
    }


    @Override
    public ResourceConfig configure() {
        return new ResourceConfig()
                .register(TestResource.class)
                .register(MultiPartFeature.class)
                .register(new LoggingFilter(Logger.getAnonymousLogger(), true))
                .register(new ExceptionMapper<Throwable>() {
                    @Override
                    public Response toResponse(Throwable t) {
                        t.printStackTrace();
                        return Response.serverError().entity(t.getMessage()).build();
                    }
                });
    }

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

    @Test
    public void testWithBody() {
        final MultiPart multiPart = new FormDataMultiPart()
                .field("test", "testing");

        final Response response = target("test")
                .request()
                .post(Entity.entity(multiPart, multiPart.getMediaType()));

        assertEquals(200, response.getStatus());
        assertEquals("testing", response.readEntity(String.class));
    }

    @Test
    public void withoutBody() {
        final Response response = target("test")
                .request()
                .post(null);

        assertEquals(200, response.getStatus());
        assertEquals("no body", response.readEntity(String.class));
    }
}