how to use spring webflux for file streaming

Question

I want to stream a file in a reactive way using spring webflux.
How my endpoint should look like more specific what is the type of the object ?

@GetMapping("/file")
Flux<???> file() {
    //Read file content into this ??? thing . 
}

score 5 · Accepted Answer · answered Aug 25 '17 at 08:21

5

You can return a Resource instance like this:

@GetMapping("/file")
Mono<Resource> file() {
    //Create a ClassPathResource, for example
}

Note that this supports Byte Range HTTP requests automatically.

answered Aug 25 '17 at 08:21

Brian Clozel

Would you mind commenting a little more on the automatic Byte Range request? If read the answer of bgraves in https://stackoverflow.com/questions/20634603/how-do-i-return-a-video-with-spring-mvc-so-that-it-can-be-navigated-using-the-ht what seems to state the opposite? – PeMa Jul 29 '18 at 18:51
1

bgraves mentioned https://jira.spring.io/browse/SPR-13834 which is now resolved. That question was about Spring MVC but the same applies now to Spring WebFlux (which came later) – Brian Clozel Jul 29 '18 at 18:57
Great, thank you a lot. That's good news. Now I just need to find out, how I make Videogular understand GridFsResource. Somehow this doesn't seem to work, while FileSystemResource worked. – PeMa Jul 29 '18 at 19:27
1

Does that resource implementation gives its content length information? If not, the resource range algorithm might opt out in that case. Try asking a new question for that showing a sample application. – Brian Clozel Jul 29 '18 at 19:32
Yes, it does have `contentLength()` method. However, I'll probably ask another question soon. Thanks for your hint anyway. – PeMa Jul 29 '18 at 19:34
Ok, works already. I missed `produces = "video/mp4"` option in the get mapping. Perfect. – PeMa Jul 29 '18 at 19:42

1 Answers1