使用 Spark Java 通过 http 流式传输视频文件

Question

我正在尝试流式传输视频文件，我正在尝试实现类似于 Jersey 的东西，如下所示：

      ResponseBuilder builder = Response.ok(out.toByteArray());
      builder.header("Content-Disposition", "attachment; filename=" + fields.get("filename"));
      response = builder.build();
    } else {
      response = Response.status(404).
          entity(" Unable to get file with ID: " + id).
          type("text/plain").
          build();
    }

    return response;
  }

这是我用于文件上传和下载/流式传输的内容（下载半成品，文件大小因损坏而正确）：

我真的需要大家帮忙，谢谢

更新

改变了：

ByteArrayOutputStream out =  new ByteArrayOutputStream();

到：

ServletOutputStream out = res.raw().getOutputStream();

更新 2 好的，我终于让它工作了，视频在浏览器中播放，但现在得到了一个 Jetty io.EofException，我关闭了流，但仍然必须是简单的。

下面是前后对比：

从浏览器下载文件是可行的，但我怎样才能直接在浏览器中流式传输呢？

之前（没用）

    //download a video/ trying to stream it right in the browser if possible
    get("/post/:id", (req, res ) -> {

            res.raw().setContentType("application/octet-stream");

            String id = req.params(":id");

            ObjectId objectId = new ObjectId(id);
            BasicDBObject query = new BasicDBObject();

            query.put("_id", objectId);
            //DBObject video = collection.findOne(query);

            GridFS gridfile = new GridFS(db, "videos");
            GridFSDBFile gridFSDBFile = gridfile.findOne(query);
            res.raw().setHeader("Content-Disposition", "attachment; filename=" + gridFSDBFile.getFilename());

            InputStream inputStream = gridFSDBFile.getInputStream();

             ServletOutputStream out = res.raw().getOutputStream();
            // ByteArrayOutputStream out =  new ByteArrayOutputStream();
            int data = inputStream.read();
            while (data >= 0) {
                out.write((char) data);
                data = inputStream.read();
            }
            out.flush();
            out.close();
            return out;
        });

AFTER（这很好用，但会出现文件结束异常）：

   get("/post/:id", (req, res ) -> {
            //what's the difference between these 2?
            res.raw().setContentType("video/mp4");
            res.type("video/mp4");

            String id = req.params(":id");

            ObjectId objectId = new ObjectId(id);
            BasicDBObject query = new BasicDBObject();

            query.put("_id", objectId);
            GridFS gridfile = new GridFS(db, "videos");
            GridFSDBFile gridFSDBFile = gridfile.findOne(query);

            res.raw().setContentLengthLong(gridFSDBFile.getLength());
            InputStream inputStream = gridFSDBFile.getInputStream();

            ServletOutputStream out = res.raw().getOutputStream();

            int data = inputStream.read();
            while (data >= 0) {
                gridFSDBFile.writeTo(out);
                data = inputStream.read();
            }

           // out.flush();
           out.close();

           return 200;

        });

上传：

 post("/postvideo/:username", (req, res) -> {
            MultipartConfigElement multipartConfigElement =
                    new MultipartConfigElement("/tmp");
            req.raw().
                    setAttribute("org.eclipse.jetty.multipartConfig",
                            multipartConfigElement);
            String username = req.params(":username");
            double[] location =
                    new double[2];
            double lattitude =
                    Double.parseDouble(req.queryParams("lat"));
            double longitude =
                    Double.parseDouble(req.queryParams("lon"));
            location[0] = lattitude;
            location[1] = longitude;

            InputStream inputStream = req.raw().getPart("file").getInputStream();;

            Part uploadedFile = req.raw().getPart("file");
            // File file = new File(uploadedFile.getName());
            GridFS gridFS = new GridFS(db, "videos");

            GridFSInputFile gfsFile = gridFS.createFile(inputStream);

            gfsFile.put("location", location);
            gfsFile.put("username", username);
            gfsFile.put("contentType", req.raw().getContentType());
            gfsFile.put("filename", uploadedFile.getSubmittedFileName());
            collection.insert(gfsFile);

            gfsFile.save();
            return 201;
        });

Answer 1

这是有效的方法。我将上传一个解决方案，让您也可以跳到视频的各个部分，小菜一碟；）

  get("/post/:id", (req, res ) -> {
        //what's the difference between these 2?
        res.raw().setContentType("video/mp4");
        res.type("video/mp4");

        String id = req.params(":id");

        ObjectId objectId = new ObjectId(id);
        BasicDBObject query = new BasicDBObject();

        query.put("_id", objectId);
        GridFS gridfile = new GridFS(db, "videos");
        GridFSDBFile gridFSDBFile = gridfile.findOne(query);

        res.raw().setContentLengthLong(gridFSDBFile.getLength());
        InputStream inputStream = gridFSDBFile.getInputStream();

        ServletOutputStream out = res.raw().getOutputStream();

        int data = inputStream.read();
        while (data >= 0) {
            gridFSDBFile.writeTo(out);
            data = inputStream.read();
        }

       // out.flush();
       out.close();

       return 200;

    });