[stable29] Migration Attributes

[backportbot]

Backport of #46476+#47069

This is a light backport of the Migration Attributes + Metadata Manager adding the features to:

• download metadata from download server,
• convert them to Attributes and uses the description() method to obtain human readable content,
• add the migrations:preview occ command to display future migrations

The backport removes the part of creating metadata based on local content, as it is useless for NC29, and not compat for php 8.0

[ChristophWurst]

This PR adds a new API. Are you sure this will be backported?

[AndyScherzinger]

Discussion/Decision has been to have it backported to v29, so people can "experience" the new feature when updating to v30 - given that we judge this change to be low/no risk. Thus adding @sorbaugh to clarify/ensure this.

[skjnldsv]

Discussion/Decision has been to have it backported to v29, so people can "experience" the new feature when updating to v30 - given that we judge this change to be low/no risk

As always, features = minor.
Backporting features is an antipattern, which would be safe to avoid.

[nickvergessen]

Maybe we can wait until it was tested a couple of times during the 30 beta/rc updates?

[AndyScherzinger]

Maybe we can wait until it was tested a couple of times during the 30 beta/rc updates?

During the betas sure, maybe RC1 / RC2 max, else there isn't enough time to actually get feedback for it.

[nickvergessen]

well the updates within the 30 beta X to beta X+1 also use this right? not only the updates from 29 to 30

[AndyScherzinger]

well the updates within the 30 beta X to beta X+1 also use this right? not only the updates from 29 to 30

Yes. My point is rather when we consider it "the last point in time we are (relatively) fine with merging it", hence I do not want to wait until the very last minute before that v29 package is build and released but also respect v29 release timelines.

[github-advanced-security]

Psalm found more than 20 potential problems in the proposed changes. Check the Files changed tab for more details.

[ArtificialOwl]

• only the part to parse metadata files is kept available from the API and occ command
• to stay compatible with php 8.0, enums IndexType and ColumnType are removed, and will just be ignored when deserializing Migrations Attributes from metadata files

[ArtificialOwl]

result when used with current nc30beta3 metadata

[AndyScherzinger]

@ArtificialOwl beyond testing if the occ command works, did (and if not can) you test that the 29+PR upgraded to 30-master (with above annotated migrations) still runs through smoothly? That would be a pre-requisite in terms of test-set that should be checked before merging this PR.

[juliusknorr]

Looks good with one question.

Also please update the issue description to reflect the current state of the partial backport. Currently it looks like there is still work to do but the diff seems fine

[ArtificialOwl]

I have updated the description of the PR

[ArtificialOwl]

@ArtificialOwl beyond testing if the occ command works, did (and if not can) you test that the 29+PR upgraded to 30-master (with above annotated migrations) still runs through smoothly? That would be a pre-requisite in terms of test-set that should be checked before merging this PR.

i will test 29.0.4+PR with an upgrade to 30.0.0beta5 after its release at the end of this week. (But I see no reason for a fail)

[AndyScherzinger]

Thanks a lot @ArtificialOwl 👍👍👍

[AndyScherzinger]

Testing has been reported as being successful upgrading 29+this-pr to v30-pre-releases