Index arbitrary labels (#317)

* Add more fields to index when sql-caching is on.

* Restore the gvkKey helper, add event fields.

The UI team wasn't sure whether the event fields should go in the empty-string group or in 'events.k8s.io',
so let's go with both until/unless specified otherwise.

* More fixes to the fields to index:

- Remove the erroneously added management.cattle.io.nodes fields
- Use the builtin Event class, not events.k8s.io (by looking at the dashboard client code)

* Start on the virtual-field work.

* Map `Event.type` to `Event._type` for indexing.

* Add a unit test for field replacement for Event.type

* Add label processing.

* Don't test for transformation of event objects in the common module.

* Parse metadata.label queries differently.

* Improve a variable name that turned out to not be temporary.

* No need to specifically cache certain labels, as all are now cached.

* Add a test to verify simple label (m.labels.foo=blah) queries work.

* 'addLabelFields' never returns an error.

* Delete superseded function.

* Was calling 'addLabelFields' one time too many.

* Start using k8s ParseToRequirements

* Pull in the k8s parser.

* Successfully test for quotation marks.

* Add quoted strings to the lexer.

* Move to a forked k8s label lexer to include non-label tests.

* Improve and test the way quoted strings in the query are detected.

* Reinstate the original Apache license in the derived code.

Following clause 4.3 of the Apache license:
"You must cause any modified files to carry prominent notices stating that You changed the files..."

* Ignore case for operators.

* Test IN multiple-target-values

* Test the not-in operator.

* Ignore case for operators.

SQL is case-insensitive on field names and values, so this just adds consistency.

* Added tests for parsing EXISTS and NOT-EXISTS queries.

* Parse less-than and greater-than ops

* Lasso's `CacheFor` now takes a `watchable` argument.

* Support 'gt' and 'lt' as synonyms for '<' and '>'.

I see both types of operators being bandied about -- it's easy to support the aliases.

* typo fix

* Have the filter parser allow exist tests only on labels.

Also reduce the case where there's no namespace function.

* Specify hard-wired fields to index alphabetically.

* Remove unused variable.

* Parser: 'metadata.labels[FIELD]' is valid

* Pull in new gvk fields from main (and keep in alpha order).

* Fixed a couple of drops done during the last rebase.

* Add a reminder to keep the entries in alpha order.

* Test TransformLabels

* Remove TransformLabels

* Remove unused/unneeded code.

* Describe diffs between our label-selector parser and upstream's.

* Use the merged lasso 46333 work.

* Drop unused field.

* Tighten up the code.

* Specify which commit the label selector parser is based on.

* Allow both single-quoted and double-quoted value matching, doc difference.

* More review-driven changes:

- Stricter processing of m.l.name keys:
  Require ending close-bracket for a start-bracket

- Comment fix

- Moving sql processing from lasso to steve: some changes missed in rebase

* Drop support for double-quotes for string values.

For now on only single-quotes (or none where possible) are allowed.

* Renaming and dropping an init block.

* Quoted strings are dropped from the filter queries

In particular, label values have a specific syntax: they must
start and end with a letter, and their innards may contain
only alnums '.', '-' and '_'.  So there's no need for quoting.

And that means now that `=` and `==` do exact matches,
and the `~` operator does a partial match.

`!=` and `!~` negate -- note that `!~` is a stricter operation than `!=`,
in that given a set of possible string values, `!=` will accept more
of them than `!~`. Maybe I shouldn't have gone here, but these operators
reminded me of learning about `nicht durfen` and `nicht sollen` in German,
or something like that.

* Move a constant definition to the module level.

* Remove commented-out code.

* Remove unused func and adjacent redundant comment.

pkg/stores/sqlproxy/proxy_store.go

@@ -57,8 +57,9 @@ const (
 )
 
 var (
-	paramScheme               = runtime.NewScheme()
-	paramCodec                = runtime.NewParameterCodec(paramScheme)
+	paramScheme = runtime.NewScheme()
+	paramCodec  = runtime.NewParameterCodec(paramScheme)
+	// Please keep the gvkKey entries in alphabetical order, on a field-by-field basis
 	typeSpecificIndexedFields = map[string][][]string{
 		gvkKey("", "v1", "ConfigMap"): {
 			{"metadata", "labels[harvesterhci.io/cloud-init-template]"}},
@@ -307,11 +308,13 @@ func (s *Store) initializeNamespaceCache() error {
 	// get any type-specific fields that steve is interested in
 	fields = append(fields, getFieldForGVK(gvk)...)
 
-	// get the type-specifc transform func
+	// get the type-specific transform func
 	transformFunc := s.transformBuilder.GetTransformFunc(gvk)
 
 	// get the ns informer
-	nsInformer, err := s.cacheFactory.CacheFor(fields, transformFunc, &tablelistconvert.Client{ResourceInterface: client}, attributes.GVK(&nsSchema), false, true)
+	tableClient := &tablelistconvert.Client{ResourceInterface: client}
+	attrs := attributes.GVK(&nsSchema)
+	nsInformer, err := s.cacheFactory.CacheFor(fields, transformFunc, tableClient, attrs, false, true)
 	if err != nil {
 		return err
 	}
@@ -750,8 +753,10 @@ func (s *Store) ListByPartitions(apiOp *types.APIRequest, schema *types.APISchem
 	fields := getFieldsFromSchema(schema)
 	fields = append(fields, getFieldForGVK(gvk)...)
 	transformFunc := s.transformBuilder.GetTransformFunc(gvk)
-
-	inf, err := s.cacheFactory.CacheFor(fields, transformFunc, &tablelistconvert.Client{ResourceInterface: client}, attributes.GVK(schema), attributes.Namespaced(schema), controllerschema.IsListWatchable(schema))
+	tableClient := &tablelistconvert.Client{ResourceInterface: client}
+	attrs := attributes.GVK(schema)
+	ns := attributes.Namespaced(schema)
+	inf, err := s.cacheFactory.CacheFor(fields, transformFunc, tableClient, attrs, ns, controllerschema.IsListWatchable(schema))
 	if err != nil {
 		return nil, 0, "", err
 	}