add canary-weight-total annotation (#6338)

internal/ingress/annotations/canary/main.go

@@ -32,6 +32,7 @@ type canary struct {
 type Config struct {
 	Enabled       bool
 	Weight        int
+	WeightTotal   int
 	Header        string
 	HeaderValue   string
 	HeaderPattern string
@@ -59,6 +60,11 @@ func (c canary) Parse(ing *networking.Ingress) (interface{}, error) {
 		config.Weight = 0
 	}
 
+	config.WeightTotal, err = parser.GetIntAnnotation("canary-weight-total", ing)
+	if err != nil {
+		config.WeightTotal = 100
+	}
+
 	config.Header, err = parser.GetStringAnnotation("canary-by-header", ing)
 	if err != nil {
 		config.Header = ""

internal/ingress/controller/controller.go

@@ -896,6 +896,7 @@ func (n *NGINXController) createUpstreams(data []*ingress.Ingress, du *ingress.B
 				upstreams[defBackend].NoServer = true
 				upstreams[defBackend].TrafficShapingPolicy = ingress.TrafficShapingPolicy{
 					Weight:        anns.Canary.Weight,
+					WeightTotal:   anns.Canary.WeightTotal,
 					Header:        anns.Canary.Header,
 					HeaderValue:   anns.Canary.HeaderValue,
 					HeaderPattern: anns.Canary.HeaderPattern,

internal/ingress/types.go

@@ -111,10 +111,15 @@ type Backend struct {
 // alternative backend
 // +k8s:deepcopy-gen=true
 type TrafficShapingPolicy struct {
-	// Weight (0-100) of traffic to redirect to the backend.
-	// e.g. Weight 20 means 20% of traffic will be redirected to the backend and 80% will remain
-	// with the other backend. 0 weight will not send any traffic to this backend
+	// Weight (0-<WeightTotal>) of traffic to redirect to the backend.
+	// e.g. <WeightTotal> defaults to 100, weight 20 means 20% of traffic will be
+	// redirected to the backend and 80% will remain with the other backend. If
+	// <WeightTotal> is set to 1000, weight 2 means 0.2% of traffic will be
+	// redirected to the backend and 99.8% will remain with the other backend.
+	// 0 weight will not send any traffic to this backend
 	Weight int `json:"weight"`
+	// The total weight of traffic (>= 100). If unspecified, it defaults to 100.
+	WeightTotal int `json:"weightTotal"`
 	// Header on which to redirect requests to this backend
 	Header string `json:"header"`
 	// HeaderValue on which to redirect requests to this backend