Ruler: Rule group not found API message

[gotjosh]

We copied over the ruler code as part of #5089, and it seems that at the same time we stopped depending on the object storage implementation of Cortex. Turns out, there are (slight) differences between the clients which meant that response returned by the API when we try to get a rule group that is not found had changed.

This ensures that is consistent with the error assertion that we have in the code for the ruler.

loki/pkg/ruler/rulestore/objectclient/rule_store.go

Lines 56 to 63 in 7fafe94

	if err != nil {
	if err.Error() == chunk.ErrStorageObjectNotFound.Error() {
	level.Debug(o.logger).Log("msg", "rule group does not exist", "name", objectKey)
	return nil, errors.Wrapf(rulestore.ErrGroupNotFound, "get rule group user=%q, namespace=%q, name=%q", rg.GetUser(), rg.GetNamespace(), rg.GetName())
	}
	return nil, errors.Wrapf(err, "failed to get rule group %s", objectKey)
	}

Checklist

• Documentation added
• Tests updated
• Add an entry in the CHANGELOG.md about the changes.

[CLAassistant]

All committers have signed the CLA.

[dannykopping]

LGTM

[kavirajk]

LGTM

[dannykopping]

LGTM