Enable app specific preview URL

[starypatyk]

This PR is related to the nextcloud/photos#1602 in the Photos app, and yet another alternative proposal to #1431.

I agree with @pulsejet comment here: #1431 (comment). Some help from Viewer is needed to support use cases like public albums in Photos.

I am very much open to alternative solutions - e.g. like this: #1431 (comment)

I think it would be really good to pick one - even if not perfect in the long run. The issue with public albums stays open for some time already.

I am missing such function that used to be in the Gallery app (now discontinued) a few years ago. 😞

[simonspa]

Seconded, in Photos right now trying to open a photo added by another user in a common album results in:
(Firefox console, local dev setup)

GEThttp://localhost:8210/index.php/core/preview?fileId=10&x=2048&y=1152&a=true
[HTTP/1.1 404 Not Found 121ms]

Loading of file preview 10-photo-1498855592392-af2bf1e0a4c7.jpeg failed, falling back to original file [Images.vue:242](webpack:///viewer/src/components/Images.vue)

Error loading /photos/bob/sharedalbums/shared_with_bob (admin)/10-photo-1498855592392-af2bf1e0a4c7.jpeg 
error { target: img.viewer__file.viewer__file--active, isTrusted: true, srcElement: img.viewer__file.viewer__file--active, currentTarget: img.viewer__file.viewer__file--active, eventPhase: 2, bubbles: false, cancelable: false, returnValue: true, defaultPrevented: false, composed: false, … }

So the core/preview route is attempted.

[skjnldsv]

Please rebase and compile assets :)

[skjnldsv]

/backport to stable25

[szaimen]

conflicts...

[starypatyk]

Please rebase and compile assets :)

Rebased and compiled assets 😉

[backportbot-nextcloud]

The backport to stable25 failed. Please do this backport manually.

[skjnldsv]

@starypatyk care to backport this to the stable25 branch? :)

[szaimen]

backport to stable25 here: #1536