feat(CustomResourceState): Support quantities

Author: mrueg

docs/customresourcestate-metrics.md

@@ -254,6 +254,7 @@ Supported types are:
 * for string the following logic applies
   * `"true"` and `"yes"` are mapped to `1.0` and `"false"` and `"no"` are mapped to `0.0` (all case insensitive)
   * RFC3339 times are parsed to float timestamp  
+  * Quantities like "250m" or "512Gi" are parsed to float using https://github.com/kubernetes/apimachinery/blob/master/pkg/api/resource/quantity.go
   * finally the string is parsed to float using https://pkg.go.dev/strconv#ParseFloat which should support all common number formats. If that fails an error is yielded
 
 ##### Example for status conditions on Kubernetes Controllers

pkg/customresourcestate/registry_factory.go

@@ -25,6 +25,7 @@ import (
 	"strings"
 	"time"
 
+	"k8s.io/apimachinery/pkg/api/resource"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/klog/v2"
 
@@ -690,16 +691,22 @@ func toFloat64(value interface{}, nilIsZero bool) (float64, error) {
 		}
 		return 0, nil
 	case string:
+		// The string contains a boolean as a string
 		normalized := strings.ToLower(value.(string))
 		if normalized == "true" || normalized == "yes" {
 			return 1, nil
 		}
 		if normalized == "false" || normalized == "no" {
 			return 0, nil
 		}
+		// The string contains a RFC3339 timestamp
 		if t, e := time.Parse(time.RFC3339, value.(string)); e == nil {
 			return float64(t.Unix()), nil
 		}
+		// The string contains a quantity with a suffix like "25m" (milli) or "5Gi" (binarySI)
+		if t, e := resource.ParseQuantity(value.(string)); e == nil {
+			return t.AsApproximateFloat64(), nil
+		}
 		return strconv.ParseFloat(value.(string), 64)
 	case byte:
 		v = float64(vv)

pkg/customresourcestate/registry_factory_test.go

@@ -64,7 +64,9 @@ func init() {
 					"ready":  4,
 				},
 			},
-			"uptime": 43.21,
+			"uptime":            43.21,
+			"quantity_milli":    "250m",
+			"quantity_binarySI": "5Gi",
 			"condition_values": Array{
 				Obj{
 					"name":  "a",
@@ -225,6 +227,20 @@ func Test_values(t *testing.T) {
 		}, wantResult: []eachValue{
 			newEachValue(t, 1656374400),
 		}},
+		{name: "quantity_milli", each: &compiledGauge{
+			compiledCommon: compiledCommon{
+				path: mustCompilePath(t, "status", "quantity_milli"),
+			},
+		}, wantResult: []eachValue{
+			newEachValue(t, 0.25),
+		}},
+		{name: "quantity_binarySI", each: &compiledGauge{
+			compiledCommon: compiledCommon{
+				path: mustCompilePath(t, "status", "quantity_binarySI"),
+			},
+		}, wantResult: []eachValue{
+			newEachValue(t, 5.36870912e+09),
+		}},
 		{name: "boolean_string", each: &compiledGauge{
 			compiledCommon: compiledCommon{
 				path: mustCompilePath(t, "spec", "paused"),