如何从Spring Boot端点为JavaScript客户端流式传输媒体内容

Question

I have a spring boot rest service with endpoints defined like this:

@RequestMapping(value = "...", method = RequestMethod.GET, produces = MediaType.IMAGE_JPEG_VALUE) //and octet for videos
@ResponseBody
public ResponseEntity<byte[]> get(...) {
   //get image as byte array and return
}

And the client side in javascript (angular) :

var headers = {headers : {..., "Accept":"image/jpeg"}}
var response = $http.get(...);
obj.imageSrc = 'data:image/jpg;base64,' + response;
obj.Image = new Image();
obj.Image.src = obj.imageSrc;

What I require

I thought this endpoint would behave like a regular image file on a file server so that the client can just do a get on it (for reasons outside the scope of this question, it can't actually be a raw image to access with a URL). Apparently this isn't the case - the byte array has to be converted to base64 (is there a way around this, since the array becomes much bigger), which has the effect of rotating the image. I wrongly thought getting an image from an API like this in javascript would be easy :(

Secondly, doing it this way means that javascript has to download the entire array. Is there a way I can define the endpoint to allow for a stream so that javascript can get it in chunks (I imagine both Spring and JS have utility functions that would handle this?)

The basic underlying question

How do I implement this properly in Spring so as to be as Javascript friendly as possible? Bearing in mind I want to serve both images (~5MB) and videos (~100MB)

Thanks in advance.

EDIT Perhaps I should be using FileResourceStream as the return type? No idea if this is the "right" way.

Answer 1

1) Don't use a data url. Use the direct url of your controller-method.

2) Write directly to the http-response's output:

@RequestMapping(value = "/dyna.jpg", method = RequestMethod.GET, produces = MediaType.IMAGE_JPEG_VALUE)
public void getImage(HttpServletResponse response) {
    //write byte-array or -stream to the response using
    // response.getOutputStream() 
}

PS In case you really need the data url there is no otherway around as you do it, since they require the base64 encoding