[v2.9] Virtual Resource filters (#288)

Adds logic which adds virtual fields resources. This allows these fields
to be sorted/filtered on when the SQL cache is enabled. Id and
metadata.state.name were added as the first two fields.

Co-authored-by: Michael Bolot <michael.bolot@suse.com>

pkg/resources/virtual/common/common.go

@@ -0,0 +1,116 @@
+// Package common provides cache.TransformFunc's which are common to all types
+package common
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/rancher/steve/pkg/summarycache"
+	"github.com/rancher/wrangler/v3/pkg/data"
+	wranglerSummary "github.com/rancher/wrangler/v3/pkg/summary"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/client-go/tools/cache"
+)
+
+// SummaryCache provides an interface to get a summary/relationships for an object. Implemented by the summaryCache
+// struct from pkg/summarycache
+type SummaryCache interface {
+	SummaryAndRelationship(runtime.Object) (*wranglerSummary.SummarizedObject, []summarycache.Relationship)
+}
+
+// DefaultFields produces a VirtualTransformFunc through GetTransform() that applies to all k8s types
+type DefaultFields struct {
+	Cache SummaryCache
+}
+
+// GetTransform produces the default transformation func
+func (d *DefaultFields) GetTransform() cache.TransformFunc {
+	return d.transform
+}
+
+// transform implements virtual.VirtualTransformFunc, and adds reserved fields/summary
+func (d *DefaultFields) transform(obj any) (any, error) {
+	raw, isSignal, err := getUnstructured(obj)
+	if isSignal {
+		return obj, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	raw = addIDField(raw)
+	raw, err = addSummaryFields(raw, d.Cache)
+	if err != nil {
+		return nil, fmt.Errorf("unable to add summary fields: %w", err)
+	}
+	return raw, nil
+}
+
+// addSummaryFields adds the virtual fields for object state.
+func addSummaryFields(raw *unstructured.Unstructured, cache SummaryCache) (*unstructured.Unstructured, error) {
+	s, relationships := cache.SummaryAndRelationship(raw)
+	if s != nil {
+		data.PutValue(raw.Object, map[string]interface{}{
+			"name":          s.State,
+			"error":         s.Error,
+			"transitioning": s.Transitioning,
+			"message":       strings.Join(s.Message, ":"),
+		}, "metadata", "state")
+
+	}
+	var rels []any
+	for _, relationship := range relationships {
+		rel, err := toMap(relationship)
+		if err != nil {
+			return nil, fmt.Errorf("unable to convert relationship to map: %w", err)
+		}
+		rels = append(rels, rel)
+	}
+	data.PutValue(raw.Object, rels, "metadata", "relationships")
+
+	normalizeConditions(raw)
+	return raw, nil
+}
+
+// addIDField adds the ID field based on namespace/name, and moves the current id field to _id if present
+func addIDField(raw *unstructured.Unstructured) *unstructured.Unstructured {
+	objectID := raw.GetName()
+	namespace := raw.GetNamespace()
+	if namespace != "" {
+		objectID = fmt.Sprintf("%s/%s", namespace, objectID)
+	}
+	currentIDValue, ok := raw.Object["id"]
+	if ok {
+		raw.Object["_id"] = currentIDValue
+	}
+	raw.Object["id"] = objectID
+	return raw
+}
+
+func normalizeConditions(raw *unstructured.Unstructured) {
+	var (
+		obj           data.Object
+		newConditions []any
+	)
+
+	obj = raw.Object
+	for _, condition := range obj.Slice("status", "conditions") {
+		var summary wranglerSummary.Summary
+		for _, summarizer := range wranglerSummary.ConditionSummarizers {
+			summary = summarizer(obj, []wranglerSummary.Condition{{Object: condition}}, summary)
+		}
+		condition.Set("error", summary.Error)
+		condition.Set("transitioning", summary.Transitioning)
+
+		if condition.String("lastUpdateTime") == "" {
+			condition.Set("lastUpdateTime", condition.String("lastTransitionTime"))
+		}
+		// needs to be reconverted back to a map[string]any or we can have encoding problems with unregistered types
+		var mapCondition map[string]any = condition
+		newConditions = append(newConditions, mapCondition)
+	}
+
+	if len(newConditions) > 0 {
+		obj.SetNested(newConditions, "status", "conditions")
+	}
+}