Add missing information to the S3 Object Storage page

[JammingBen]

WHAT Needs to be Documented?

The S3 Object Storage page included a lot of information in the past about how to set it up, what to pay attention to etc. (see https://cc.bingj.com/cache.aspx?q=owncloud+ceph+s3+encryption&d=4522776899816615&mkt=de-DE&setlang=de-DE&w=lbfPOfz2KnsIuM2HFNtPsLLsVA-UGidI). This information seems to be gone nowadays?
This came up because apparently, encryption is not compatible with the S3 Object Storage. That's definitely information that our users need!

WHERE Does This Need To Be Documented (Link)?

https://doc.owncloud.com/server/10.8/admin_manual/configuration/server/occ_commands/app_commands/s3objectstore_commands.html

(Optional) What Type Of Content Change Is This?

• New Content Addition
• Old Content Deprecation
• Existing Content Simplification
• Bug Fix to Existing Content

(Optional) Which Manual Does This Relate To?

• Admin Manual
• Developer Manual
• User Manual
• Android
• iOS
• Branded Clients
• Desktop Client
• Other

[JammingBen]

@mmattel Do you know anything why this info has been removed or where it has been moved to?

[mmattel]

@JammingBen honestly no clue, but I will take a look. A deletion/removal/unlink is not intended...

[mmattel]

@JammingBen is it this what you are looking for?

https://doc.owncloud.com/server/10.8/admin_manual/configuration/files/external_storage/amazons3.html (next / 10.8 / 10.7)

Note, any reference to OpenStack Swift has been removed on 18 Nov 2019 by #2087 (Remove final references to Swift from the documentation)

[JammingBen]

https://github.com/owncloud/docs/pull/2087/files#diff-affd8294f289123cd369842cf906ba8e27624be73d5e8fd16045aa59474ce389 is what I was looking for. Unfortunately I don't know what parts of this information are still relevant, at least the encryption chapter is:

3. The current implementation is incompatible with any app that uses direct file I/O (input/output) as it circumvents the ownCloud virtual filesystem. An excellent example is the Encryption app, which fetches critical files in addition to any requested file, which results in significant overhead.

[AlexAndBear]

@mmattel https://doc.owncloud.com/server/10.8/admin_manual/configuration/files/external_storage/amazons3.html is for external storage configuration.

We are looking for the configuration as primary storage so this needs to be restored:
https://github.com/owncloud/docs/pull/2087/files#diff-affd8294f289123cd369842cf906ba8e27624be73d5e8fd16045aa59474ce389

Otherwise, there is no documentation how to enable s3 as primary storage, and the app is quite useless :(

OFC we can remove the swift paragraphs

[mmattel]

ok, got that one.
I will prepare a PR containing the Object Store configuration. Will invite for a review when ready.

[mmattel]

While further digging, the marketplace (https://marketplace.owncloud.com/apps/files_primary_s3) links to https://doc.owncloud.com/server/latest/admin_manual/enterprise/external_storage/s3_swift_as_primary_object_store_configuration.html which results in a 404 as the page has been removed, see #2087 (Remove final references to Swift from the documentation)