feat(circuit-breaker): add the circuit breaker feature

Author: julius-malcovsky

admin/api/v1/zone_types.go

@@ -44,6 +44,8 @@ type GatewayAdminConfig struct {
 type GatewayConfig struct {
 	Admin GatewayAdminConfig `json:"admin"`
 	Url   string             `json:"url"`
+	// CircuitBreaker flag that controls if circuit breaker should be enabled on this zone. the config of the CB itself comes from hardcoded values, not configurable
+	CircuitBreaker bool `json:"circuitBreaker"`
 }
 
 type ApiConfig struct {

admin/config/crd/bases/admin.cp.ei.telekom.de_zones.yaml

@@ -55,10 +55,16 @@ spec:
                     required:
                     - clientSecret
                     type: object
+                  circuitBreaker:
+                    description: CircuitBreaker flag that controls if circuit breaker
+                      should be enabled on this zone. the config of the CB itself
+                      comes from hardcoded values, not configurable
+                    type: boolean
                   url:
                     type: string
                 required:
                 - admin
+                - circuitBreaker
                 - url
                 type: object
               identityProvider:

admin/internal/handler/zone/handler.go

@@ -322,6 +322,7 @@ func createGateway(ctx context.Context, handlingContext HandlingContext) (*gatew
 				EnableTLS: handlingContext.Zone.Spec.Redis.EnableTLS,
 			},
 		}
+
 		return nil
 	}
 	_, err := scopedClient.CreateOrUpdate(ctx, gateway, mutator)

api/api/v1/apiexposure_types.go

@@ -98,6 +98,10 @@ func (a *ApiExposure) HasOverriddenSubscriberRateLimit() bool {
 	return len(a.Spec.Traffic.RateLimit.SubscriberRateLimit.Overrides) > 0
 }
 
+func (a *ApiExposure) HasCircuitBreaker() bool {
+	return a.Spec.Traffic.CircuitBreaker != nil
+}
+
 func (a *ApiExposure) GetOverriddenSubscriberRateLimit(subscriber string) (Limits, bool) {
 	if !a.HasOverriddenSubscriberRateLimit() {
 		return Limits{}, false

api/api/v1/traffic_types.go

@@ -17,6 +17,15 @@ type Traffic struct {
 	// RateLimit defines request rate limiting for this API
 	// +kubebuilder:validation:Optional
 	RateLimit *RateLimit `json:"rateLimit,omitempty"`
+	// CircuitBreaker defines the Kong circuit breaker configuration
+	// +kubebuilder:validation:Optional
+	CircuitBreaker *CircuitBreaker `json:"circuitBreaker,omitempty"`
+}
+
+type CircuitBreaker struct {
+	// CircuitBreaker flags if the Kong circuit breaker feature should be used
+	// kubebuilder:default=false
+	Enabled bool `json:"enabled,omitempty"`
 }
 
 type SubscriberTraffic struct {

api/api/v1/zz_generated.deepcopy.go

@@ -190,6 +190,15 @@ spec:
                 type: object
               traffic:
                 properties:
+                  circuitBreaker:
+                    description: CircuitBreaker defines the Kong circuit breaker configuration
+                    properties:
+                      enabled:
+                        description: |-
+                          CircuitBreaker flags if the Kong circuit breaker feature should be used
+                          kubebuilder:default=false
+                        type: boolean
+                    type: object
                   failover:
                     description: Failover defines the failover configuration for the
                       API exposure.

api/config/crd/bases/api.cp.ei.telekom.de_apiexposures.yaml

@@ -375,6 +375,11 @@ func CreateRealRoute(ctx context.Context, downstreamZoneRef types.ObjectRef, api
 			route.Spec.Traffic.RateLimit = mapProviderRateLimitToGatewayRateLimit(apiExposure.Spec.Traffic.RateLimit.Provider)
 		}
 
+		// switch from pointer to non-pointer (
+		if apiExposure.HasCircuitBreaker() {
+			route.Spec.Traffic.CircuitBreaker = mapCircuitBreaker(apiExposure.Spec.Traffic.CircuitBreaker)
+		}
+
 		return nil
 	}
 
@@ -529,6 +534,16 @@ func mapProviderRateLimitToGatewayRateLimit(apiRateLimitConfig *apiapi.RateLimit
 	}
 }
 
+func mapCircuitBreaker(cb *apiapi.CircuitBreaker) *gatewayapi.CircuitBreaker {
+	circuitBreaker := &gatewayapi.CircuitBreaker{}
+	if cb == nil {
+		circuitBreaker.Enabled = false
+	} else {
+		circuitBreaker.Enabled = cb.Enabled
+	}
+	return circuitBreaker
+}
+
 func mapLimitsToGatewayLimits(apiLimits apiapi.Limits) gatewayapi.Limits {
 	return gatewayapi.Limits{
 		Second: apiLimits.Second,

api/internal/handler/util/route_util.go

@@ -12,8 +12,9 @@ const (
 	FeatureTypeAccessControl        FeatureType = "AccessControl"
 	FeatureTypeRateLimit            FeatureType = "RateLimit"
 	FeatureTypeHeaderTransformation FeatureType = "HeaderTransformation"
-	FeatureTypeBasicAuth     FeatureType = "BasicAuth"
-	FeatureTypeIpRestriction FeatureType = "IpRestriction"
+	FeatureTypeBasicAuth            FeatureType = "BasicAuth"
+	FeatureTypeIpRestriction        FeatureType = "IpRestriction"
+	FeatureTypeCircuitBreaker       FeatureType = "CircuitBreaker"
 )
 
 // Dependent Features

gateway/api/v1/features.go

@@ -171,6 +171,22 @@ func (g *Route) SetServiceId(id string) {
 	g.SetProperty("serviceId", id)
 }
 
+func (g *Route) SetUpstreamId(id string) {
+	g.SetProperty("upstreamId", id)
+}
+
+func (g *Route) SetTargetsId(id string) {
+	g.SetProperty("targetsId", id)
+}
+
+func (g *Route) GetUpstreamId() string {
+	return g.GetProperty("upstreamId")
+}
+
+func (g *Route) GetTargetsId() string {
+	return g.GetProperty("targetsId")
+}
+
 func (g *Route) SetProperty(key, val string) {
 	if g.Status.Properties == nil {
 		g.Status.Properties = make(map[string]string)