feat(translator): Implement consistent hash table size in BackendTraf…

…ficPolicy (#3440) * Implement consistent hash table size api Signed-off-by: Dingkang Li <dingkang1743@gmail.com> * Use function in go/math to judge prime number Signed-off-by: Dingkang Li <dingkang1743@gmail.com> * Fix error handling Signed-off-by: Dingkang Li <dingkang1743@gmail.com> --------- Signed-off-by: Dingkang Li <dingkang1743@gmail.com>
envoyproxy · May 24, 2024 · 6782d15 · 6782d15
1 parent 8b71c60
commit 6782d15
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Showing 14 changed files with 437 additions and 18 deletions.
diff --git a/api/v1alpha1/loadbalancer_types.go b/api/v1alpha1/loadbalancer_types.go
@@ -73,7 +73,6 @@ type ConsistentHash struct {
 	// +kubebuilder:validation:Maximum=5000011
 	// +kubebuilder:default=65537
 	// +optional
-	// +notImplementedHide
 	TableSize *uint64 `json:"tableSize,omitempty"`
 }
 

diff --git a/internal/gatewayapi/backendtrafficpolicy.go b/internal/gatewayapi/backendtrafficpolicy.go
@@ -9,6 +9,7 @@ import (
 	"errors"
 	"fmt"
 	"math"
+	"math/big"
 	"net"
 	"sort"
 	"strings"
@@ -28,6 +29,10 @@ import (
 	"github.com/envoyproxy/gateway/internal/utils/regex"
 )
 
+const (
+	MaxConsistentHashTableSize = 5000011 // https://www.envoyproxy.io/docs/envoy/latest/api-v3/config/cluster/v3/cluster.proto#config-cluster-v3-cluster-maglevlbconfig
+)
+
 func (t *Translator) ProcessBackendTrafficPolicies(backendTrafficPolicies []*egv1a1.BackendTrafficPolicy,
 	gateways []*GatewayContext,
 	routes []RouteContext,
@@ -307,7 +312,10 @@ func (t *Translator) translateBackendTrafficPolicyForRoute(policy *egv1a1.Backen
 		}
 	}
 	if policy.Spec.LoadBalancer != nil {
-		lb = t.buildLoadBalancer(policy)
+		if lb, err = t.buildLoadBalancer(policy); err != nil {
+			err = perr.WithMessage(err, "LoadBalancer")
+			errs = errors.Join(errs, err)
+		}
 	}
 	if policy.Spec.ProxyProtocol != nil {
 		pp = t.buildProxyProtocol(policy)
@@ -431,7 +439,10 @@ func (t *Translator) translateBackendTrafficPolicyForGateway(policy *egv1a1.Back
 		}
 	}
 	if policy.Spec.LoadBalancer != nil {
-		lb = t.buildLoadBalancer(policy)
+		if lb, err = t.buildLoadBalancer(policy); err != nil {
+			err = perr.WithMessage(err, "LoadBalancer")
+			errs = errors.Join(errs, err)
+		}
 	}
 	if policy.Spec.ProxyProtocol != nil {
 		pp = t.buildProxyProtocol(policy)
@@ -764,12 +775,17 @@ func buildRateLimitRule(rule egv1a1.RateLimitRule) (*ir.RateLimitRule, error) {
 	return irRule, nil
 }
 
-func (t *Translator) buildLoadBalancer(policy *egv1a1.BackendTrafficPolicy) *ir.LoadBalancer {
+func (t *Translator) buildLoadBalancer(policy *egv1a1.BackendTrafficPolicy) (*ir.LoadBalancer, error) {
 	var lb *ir.LoadBalancer
 	switch policy.Spec.LoadBalancer.Type {
 	case egv1a1.ConsistentHashLoadBalancerType:
+		consistentHash, err := t.buildConsistentHashLoadBalancer(policy)
+		if err != nil {
+			return nil, perr.WithMessage(err, "ConsistentHash")
+		}
+
 		lb = &ir.LoadBalancer{
-			ConsistentHash: t.buildConsistentHashLoadBalancer(policy),
+			ConsistentHash: consistentHash,
 		}
 	case egv1a1.LeastRequestLoadBalancerType:
 		lb = &ir.LoadBalancer{}
@@ -803,24 +819,32 @@ func (t *Translator) buildLoadBalancer(policy *egv1a1.BackendTrafficPolicy) *ir.
 		}
 	}
 
-	return lb
+	return lb, nil
 }
 
-func (t *Translator) buildConsistentHashLoadBalancer(policy *egv1a1.BackendTrafficPolicy) *ir.ConsistentHash {
+func (t *Translator) buildConsistentHashLoadBalancer(policy *egv1a1.BackendTrafficPolicy) (*ir.ConsistentHash, error) {
+	consistentHash := &ir.ConsistentHash{}
+
+	if policy.Spec.LoadBalancer.ConsistentHash.TableSize != nil {
+		tableSize := policy.Spec.LoadBalancer.ConsistentHash.TableSize
+
+		if *tableSize > MaxConsistentHashTableSize || !big.NewInt(int64(*tableSize)).ProbablyPrime(0) {
+			return nil, fmt.Errorf("invalid TableSize value %d", *tableSize)
+		}
+
+		consistentHash.TableSize = tableSize
+	}
+
 	switch policy.Spec.LoadBalancer.ConsistentHash.Type {
 	case egv1a1.SourceIPConsistentHashType:
-		return &ir.ConsistentHash{
-			SourceIP: ptr.To(true),
-		}
+		consistentHash.SourceIP = ptr.To(true)
 	case egv1a1.HeaderConsistentHashType:
-		return &ir.ConsistentHash{
-			Header: &ir.Header{
-				Name: policy.Spec.LoadBalancer.ConsistentHash.Header.Name,
-			},
+		consistentHash.Header = &ir.Header{
+			Name: policy.Spec.LoadBalancer.ConsistentHash.Header.Name,
 		}
-	default:
-		return &ir.ConsistentHash{}
 	}
+
+	return consistentHash, nil
 }
 
 func (t *Translator) buildProxyProtocol(policy *egv1a1.BackendTrafficPolicy) *ir.ProxyProtocol {

diff --git a/...estdata/backendtrafficpolicy-with-loadbalancer-invalid-consistent-hash-table-size.in.yaml b/...estdata/backendtrafficpolicy-with-loadbalancer-invalid-consistent-hash-table-size.in.yaml
@@ -0,0 +1,83 @@
+gateways:
+- apiVersion: gateway.networking.k8s.io/v1
+  kind: Gateway
+  metadata:
+    namespace: envoy-gateway
+    name: gateway-1
+  spec:
+    gatewayClassName: envoy-gateway-class
+    listeners:
+    - name: http
+      protocol: HTTP
+      port: 80
+      allowedRoutes:
+        namespaces:
+          from: All
+httpRoutes:
+- apiVersion: gateway.networking.k8s.io/v1
+  kind: HTTPRoute
+  metadata:
+    namespace: default
+    name: httproute-1
+  spec:
+    hostnames:
+    - gateway.envoyproxy.io
+    parentRefs:
+    - namespace: envoy-gateway
+      name: gateway-1
+      sectionName: http
+    rules:
+    - matches:
+      - path:
+          value: "/"
+      backendRefs:
+      - name: service-1
+        port: 8080
+- apiVersion: gateway.networking.k8s.io/v1
+  kind: HTTPRoute
+  metadata:
+    namespace: default
+    name: httproute-2
+  spec:
+    hostnames:
+    - gateway.envoyproxy.io
+    parentRefs:
+    - namespace: envoy-gateway
+      name: gateway-1
+      sectionName: http
+    rules:
+    - matches:
+      - path:
+          value: "/test2"
+      backendRefs:
+      - name: service-2
+        port: 8080
+backendTrafficPolicies:
+- apiVersion: gateway.envoyproxy.io/v1alpha1
+  kind: BackendTrafficPolicy
+  metadata:
+    namespace: default
+    name: policy-for-route
+  spec:
+    targetRef:
+      group: gateway.networking.k8s.io
+      kind: HTTPRoute
+      name: httproute-1
+    loadBalancer:
+      type: ConsistentHash
+      consistentHash:
+        tableSize: 1024
+- apiVersion: gateway.envoyproxy.io/v1alpha1
+  kind: BackendTrafficPolicy
+  metadata:
+    namespace: default
+    name: policy-for-route2
+  spec:
+    targetRef:
+      group: gateway.networking.k8s.io
+      kind: HTTPRoute
+      name: httproute-2
+    loadBalancer:
+      type: ConsistentHash
+      consistentHash:
+        tableSize: 5000012