api: add the buffer limit knob to the cluster

api/v1alpha1/backendtrafficpolicy_types.go

@@ -6,6 +6,7 @@
 package v1alpha1
 
 import (
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	gwapiv1a2 "sigs.k8s.io/gateway-api/apis/v1alpha2"
 )
@@ -103,6 +104,11 @@ type BackendTrafficPolicySpec struct {
 	// +optional
 	// +notImplementedHide
 	Compression []*Compression `json:"compression,omitempty"`
+
+	// Connection includes backend connection settings.
+	//
+	// +optional
+	Connection *BackendTrafficPolicyConnection `json:"connection,omitempty"`
 }
 
 // +kubebuilder:object:root=true
@@ -114,6 +120,18 @@ type BackendTrafficPolicyList struct {
 	Items           []BackendTrafficPolicy `json:"items"`
 }
 
+// BackendTrafficPolicyConnection allows users to configure connection-level settings of backend
+type BackendTrafficPolicyConnection struct {
+	// BufferLimit Soft limit on size of the cluster’s connections read and write buffers.
+	// If unspecified, an implementation defined default is applied (32768 bytes).
+	// For example, 20Mi, 1Gi, 256Ki etc.
+	// Note: that when the suffix is not provided, the value is interpreted as bytes.
+	//
+	// +kubebuilder:validation:XValidation:rule="type(self) == string ? self.matches(r\"^[1-9]+[0-9]*([EPTGMK]i|[EPTGMk])?$\") : type(self) == int",message="BufferLimit must be of the format \"^[1-9]+[0-9]*([EPTGMK]i|[EPTGMk])?$\""
+	// +optional
+	BufferLimit *resource.Quantity `json:"bufferLimit,omitempty"`
+}
+
 func init() {
 	SchemeBuilder.Register(&BackendTrafficPolicy{}, &BackendTrafficPolicyList{})
 }

charts/gateway-helm/crds/generated/gateway.envoyproxy.io_backendtrafficpolicies.yaml

@@ -119,6 +119,25 @@ spec:
                   - type
                   type: object
                 type: array
+              connection:
+                description: Connection includes backend connection settings.
+                properties:
+                  bufferLimit:
+                    anyOf:
+                    - type: integer
+                    - type: string
+                    description: |-
+                      BufferLimit Soft limit on size of the cluster’s connections read and write buffers.
+                      If unspecified, an implementation defined default is applied (32768 bytes).
+                      For example, 20Mi, 1Gi, 256Ki etc.
+                      Note: that when the suffix is not provided, the value is interpreted as bytes.
+                    pattern: ^(\+|-)?(([0-9]+(\.[0-9]*)?)|(\.[0-9]+))(([KMGTPE]i)|[numkMGTPE]|([eE](\+|-)?(([0-9]+(\.[0-9]*)?)|(\.[0-9]+))))?$
+                    x-kubernetes-int-or-string: true
+                    x-kubernetes-validations:
+                    - message: BufferLimit must be of the format "^[1-9]+[0-9]*([EPTGMK]i|[EPTGMk])?$"
+                      rule: 'type(self) == string ? self.matches(r"^[1-9]+[0-9]*([EPTGMK]i|[EPTGMk])?$")
+                        : type(self) == int'
+                type: object
               faultInjection:
                 description: |-
                   FaultInjection defines the fault injection policy to be applied. This configuration can be used to

site/content/en/latest/api/extension_types.md

@@ -261,6 +261,20 @@ _Appears in:_
 | `spec` | _[BackendTrafficPolicySpec](#backendtrafficpolicyspec)_ |  true  | spec defines the desired state of BackendTrafficPolicy. |
 
 
+#### BackendTrafficPolicyConnection
+
+
+
+BackendTrafficPolicyConnection allows users to configure connection-level settings of backend
+
+_Appears in:_
+- [BackendTrafficPolicySpec](#backendtrafficpolicyspec)
+
+| Field | Type | Required | Description |
+| ---   | ---  | ---      | ---         |
+| `bufferLimit` | _[Quantity](#quantity)_ |  false  | BufferLimit Soft limit on size of the cluster’s connections read and write buffers.<br />If unspecified, an implementation defined default is applied (32768 bytes).<br />For example, 20Mi, 1Gi, 256Ki etc.<br />Note: that when the suffix is not provided, the value is interpreted as bytes. |
+
+
 #### BackendTrafficPolicyList
 
 
@@ -299,6 +313,7 @@ _Appears in:_
 | `retry` | _[Retry](#retry)_ |  false  | Retry provides more advanced usage, allowing users to customize the number of retries, retry fallback strategy, and retry triggering conditions.<br />If not set, retry will be disabled. |
 | `useClientProtocol` | _boolean_ |  false  | UseClientProtocol configures Envoy to prefer sending requests to backends using<br />the same HTTP protocol that the incoming request used. Defaults to false, which means<br />that Envoy will use the protocol indicated by the attached BackendRef. |
 | `timeout` | _[Timeout](#timeout)_ |  false  | Timeout settings for the backend connections. |
+| `connection` | _[BackendTrafficPolicyConnection](#backendtrafficpolicyconnection)_ |  false  | Connection includes backend connection settings. |
 
 
 #### BasicAuth

test/cel-validation/backendtrafficpolicy_test.go

@@ -15,6 +15,7 @@ import (
 	"testing"
 	"time"
 
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/utils/ptr"
 	gwapiv1 "sigs.k8s.io/gateway-api/apis/v1"
@@ -920,6 +921,43 @@ func TestBackendTrafficPolicyTarget(t *testing.T) {
 				`[spec.rateLimit.global.rules: Too many: 65: must have at most 64 items, <nil>: Invalid value: "null": some validation rules were not checked because the object was invalid; correct the existing errors to complete validation]`,
 			},
 		},
+		{
+			desc: "valid connectionBufferLimitBytes format",
+			mutate: func(btp *egv1a1.BackendTrafficPolicy) {
+				btp.Spec = egv1a1.BackendTrafficPolicySpec{
+					TargetRef: gwapiv1a2.LocalPolicyTargetReferenceWithSectionName{
+						LocalPolicyTargetReference: gwapiv1a2.LocalPolicyTargetReference{
+							Group: gwapiv1a2.Group("gateway.networking.k8s.io"),
+							Kind:  gwapiv1a2.Kind("Gateway"),
+							Name:  gwapiv1a2.ObjectName("eg"),
+						},
+					},
+					Connection: &egv1a1.BackendTrafficPolicyConnection{
+						BufferLimit: ptr.To(resource.MustParse("1Mi")),
+					},
+				}
+			},
+		},
+		{
+			desc: "invalid connectionBufferLimitBytes format",
+			mutate: func(btp *egv1a1.BackendTrafficPolicy) {
+				btp.Spec = egv1a1.BackendTrafficPolicySpec{
+					TargetRef: gwapiv1a2.LocalPolicyTargetReferenceWithSectionName{
+						LocalPolicyTargetReference: gwapiv1a2.LocalPolicyTargetReference{
+							Group: gwapiv1a2.Group("gateway.networking.k8s.io"),
+							Kind:  gwapiv1a2.Kind("Gateway"),
+							Name:  gwapiv1a2.ObjectName("eg"),
+						},
+					},
+					Connection: &egv1a1.BackendTrafficPolicyConnection{
+						BufferLimit: ptr.To(resource.MustParse("1m")),
+					},
+				}
+			},
+			wantErrors: []string{
+				"spec.connection.bufferLimit: Invalid value: \"\": BufferLimit must be of the format \"^[1-9]+[0-9]*([EPTGMK]i|[EPTGMk])?$\"",
+			},
+		},
 	}
 
 	for _, tc := range cases {