bw test: Can we make a test that shows all “unused” metadata keys?

[vain]

I just added some metadata to a node:

'backuptool': {
    'retention': '5d',
},

It should have been this instead:

'backups': {
    'retention': '5d',
},

So, my initial change didn’t have any effect, it was just dead metadata.

Can we add something to bw test that shows all keys which are never read by anything? This would probably need a list of keys (probably in the format some/key/path to allow for deeper stuff) which should not be reported.

[trehn]

Yes, shouldn't be too hard.

[trehn]

This would have to be a test covering every node at once. Checking just a single node for unused metadata would produce many false positives (extra metadata added by a group or bundle; or metadata that is only read by another node).

[trehn]

I think the way to do this would be to build two set of metadata key paths while building the entire repo (including files). One set for every metadata key path on all nodes and another set for every path read while building the repo. When done, diff the sets. Extra credit for storing or finding the nodes with the unused paths so users won't have to do it manually.