Allow Disabling Auto Preview Generation While Keeping preview:generate-all Functionality

[diawedding]

Hi everyone,

I have a specific use case that might be relevant to other performance-conscious users as well.

I would like to disable automatic preview generation during file uploads, because it creates significant CPU load—especially when many high-resolution images are uploaded during the day. However, I still want to generate all previews manually at night using the occ preview:generate-all command via cron when the server is idle.

Unfortunately, this isn’t currently possible with the following setup:

php

KopyalaDüzenle

'enable_previews' => true,
'enabledPreviewProviders' => [],

With this configuration:

• No previews are generated during uploads (which is good)
• But preview:generate-all also doesn’t work at all (which defeats the purpose)

In contrast, if I provide preview providers like so:

php

KopyalaDüzenle

'enabledPreviewProviders' => [
  'OC\\Preview\\JPEG',
  'OC\\Preview\\PNG',
  'OC\\Preview\\GIF',
],

Then both upload-time previews and preview:generate-all start working—but again, preview generation happens during uploads, which I don’t want.

Proposed Improvement

Could we have a new config flag such as:

php

KopyalaDüzenle

'generate_previews_on_upload' => false,

This way we could:

• Keep enable_previews = true so the UI displays them
• Disable auto-generation during upload
• Still allow scheduled bulk generation at night via cron (preview:generate-all)

This would be extremely helpful for users with limited CPU or shared hosting environments, especially photographers or media-heavy users.

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Any suggestions or workarounds you’d recommend besides temporarily modifying config.php via scripting?
Thanks in advance!