How to download a file from a content store

[estebes]

When i try to download a file from the server onto the disk i get an error saying server problem and in the server log i get "java.lang.UnsupportedOperationException: null
"

[paulcwarren]

@estebes is there anymore stack trace than that? What Spring Content Module(s) are you using? Spring Content for JPA? And are you also using Spring Content REST?

A small project that reproduces this issue would be very helpful as well.

You could also cross reference your project against the relevant example in github.com/paulcwarren/spring-content-examples

[estebes]

Full log - https://pastebin.com/1rtRt1QR

Dependencies
// Spring Content >> /* https://mvnrepository.com/artifact/com.github.paulcwarren/spring-content-fs-boot-starter */ compile group: 'com.github.paulcwarren', name: 'spring-content-fs-boot-starter', version: '0.0.7-SNAPSHOT' /* https://mvnrepository.com/artifact/com.github.paulcwarren/spring-content-rest-boot-starter */ compile group: 'com.github.paulcwarren', name: 'spring-content-rest-boot-starter', version: '0.0.7-SNAPSHOT' // << Spring Content

Html code
<a href="file.pdf" download>download here</a>
This also happens when i open the content in a new tab and click save as.

I'll try to create a small project reproducing the issue.

[paulcwarren]

A project may not be necessary @estebes.

I have a theory. When you click that 'download' I think your browser might not be sending an Accept header in the request. In ContentEntityRestController (

spring-content/spring-content-rest/src/main/java/internal/org/springframework/content/rest/controllers/ContentEntityRestController.java

Line 122 in 949a73d

mimeTypes.add(MediaType.ALL);

) we call a spring class to parse the mime-types received in the request's accept header. If there aren't any it returns an immmutable list that we then try and add to. This throws the UnsupportedOperationException.

So I wonder what browser you are using and whether you could check the request it is sending.

Look forward to hearing from you.

[paulcwarren]

Yeah, I think that is what is going on. I just managed to reproduce that error in a unit tests anyways. Your context will be helpful but i am going to go ahead and fix this as it is a bug anyways.

[estebes]

So i just tried to use firefox instead of chrome and it actually works on firefox althoughit ignores the .pdf extension and downloads a .txt but yes what you described seems to be what is happening.

[paulcwarren]

I added a candidate fix for this issue in this commit:-

294fa48

Can you switchover to 0.0.8-SNAPSHOT and give it a whirl. If it fixes the issue then I'll cut a release.

[estebes]

Perfect fix. Works on both chrome and firefox. I think i can now close this issue. Thank you very much for the help.

[paulcwarren]

+1