adding BackendTimeout for Gateway API router

Signed-off-by: Danny Kulchinsky <dkulchinsky@fastly.com>

artifacts/flagger/crd.yaml

@@ -230,6 +230,9 @@ spec:
                     timeout:
                       description: HTTP or gRPC request timeout
                       type: string
+                    backendTimeout:
+                      description: Backend request timeout (Gateway API only)
+                      type: string
                     meshName:
                       description: AppMesh mesh name
                       type: string

charts/flagger/crds/crd.yaml

@@ -230,6 +230,9 @@ spec:
                     timeout:
                       description: HTTP or gRPC request timeout
                       type: string
+                    backendTimeout:
+                      description: Backend request timeout (Gateway API only)
+                      type: string
                     meshName:
                       description: AppMesh mesh name
                       type: string

docs/gitbook/tutorials/gatewayapi-progressive-delivery.md

@@ -720,6 +720,38 @@ The above procedures can be extended with [custom metrics](../usage/metrics.md)
 Besides the `hosts` and `gatewayRefs` fields, you can customize the generated HTTPRoute with various options
 exposed under the `spec.service` field of the Canary.
 
+### Timeouts
+
+You can configure request timeouts on the generated HTTPRoute using the `spec.service.timeout` and
+`spec.service.backendTimeout` fields of the Canary. Both values are
+[Gateway API Duration](https://gateway-api.sigs.k8s.io/geps/gep-2257/) strings (e.g. `5s`, `500ms`).
+
+- `timeout` maps to `HTTPRouteTimeouts.Request` and bounds the total request duration from when the gateway
+  receives the request to when the response is sent back to the client.
+- `backendTimeout` maps to `HTTPRouteTimeouts.BackendRequest` and bounds the duration of an individual
+  request from the gateway to a backend. When set together with `timeout`, `backendTimeout` must be
+  less than or equal to `timeout`.
+
+> **Note:** Timeouts require a Gateway API implementation that supports
+> [`HTTPRouteTimeouts`](https://gateway-api.sigs.k8s.io/api-types/httproute/#timeouts).
+> `backendTimeout` additionally requires support for the `BackendRequest` timeout field.
+
+Example configuration:
+
+```yaml
+apiVersion: flagger.app/v1beta1
+kind: Canary
+metadata:
+  name: podinfo
+  namespace: test
+spec:
+  service:
+    # Total request timeout (gateway to client)
+    timeout: 5s
+    # Per-attempt backend request timeout (gateway to backend)
+    backendTimeout: 2s
+```
+
 ### Header Manipulation
 
 You can configure request and response header manipulation using the `spec.service.headers` field of the Canary.

docs/gitbook/usage/how-it-works.md

@@ -230,6 +230,9 @@ spec:
       attempts: 3
       perTryTimeout: 1s
     timeout: 5s
+    # backendTimeout is only supported by the Gateway API provider and
+    # maps to HTTPRouteTimeouts.BackendRequest.
+    backendTimeout: 2s
 ```
 
 When using **Istio** as the mesh provider, you can also specify HTTP header operations,

kustomize/base/flagger/crd.yaml

@@ -230,6 +230,9 @@ spec:
                     timeout:
                       description: HTTP or gRPC request timeout
                       type: string
+                    backendTimeout:
+                      description: Backend request timeout (Gateway API only)
+                      type: string
                     meshName:
                       description: AppMesh mesh name
                       type: string

pkg/apis/flagger/v1beta1/canary.go

@@ -168,6 +168,11 @@ type CanaryService struct {
 	// +optional
 	Timeout string `json:"timeout,omitempty"`
 
+	// BackendTimeout specifies a timeout for an individual request from the gateway
+	// to a backend. Only supported by the Gateway API provider.
+	// +optional
+	BackendTimeout string `json:"backendTimeout,omitempty"`
+
 	// Gateways attached to the generated Istio virtual service
 	// Defaults to the internal mesh gateway
 	// +optional

pkg/router/gateway_api.go

@@ -108,11 +108,8 @@ func (gwr *GatewayAPIRouter) Reconcile(canary *flaggerv1.Canary) error {
 			},
 		},
 	}
-	if canary.Spec.Service.Timeout != "" {
-		timeout := v1.Duration(canary.Spec.Service.Timeout)
-		httpRouteSpec.Rules[0].Timeouts = &v1.HTTPRouteTimeouts{
-			Request: &timeout,
-		}
+	if canary.Spec.Service.Timeout != "" || canary.Spec.Service.BackendTimeout != "" {
+		httpRouteSpec.Rules[0].Timeouts = makeHTTPRouteTimeouts(canary)
 	}
 
 	// A/B testing
@@ -129,11 +126,8 @@ func (gwr *GatewayAPIRouter) Reconcile(canary *flaggerv1.Canary) error {
 				},
 			},
 		})
-		if canary.Spec.Service.Timeout != "" {
-			timeout := v1.Duration(canary.Spec.Service.Timeout)
-			httpRouteSpec.Rules[1].Timeouts = &v1.HTTPRouteTimeouts{
-				Request: &timeout,
-			}
+		if canary.Spec.Service.Timeout != "" || canary.Spec.Service.BackendTimeout != "" {
+			httpRouteSpec.Rules[1].Timeouts = makeHTTPRouteTimeouts(canary)
 		}
 	}
 
@@ -382,11 +376,8 @@ func (gwr *GatewayAPIRouter) SetRoutes(
 			},
 		},
 	}
-	if canary.Spec.Service.Timeout != "" {
-		timeout := v1.Duration(canary.Spec.Service.Timeout)
-		weightedRouteRule.Timeouts = &v1.HTTPRouteTimeouts{
-			Request: &timeout,
-		}
+	if canary.Spec.Service.Timeout != "" || canary.Spec.Service.BackendTimeout != "" {
+		weightedRouteRule.Timeouts = makeHTTPRouteTimeouts(canary)
 	}
 
 	// If B/G mirroring is enabled, then add a route filter which mirrors the traffic
@@ -439,11 +430,8 @@ func (gwr *GatewayAPIRouter) SetRoutes(
 			},
 		})
 
-		if canary.Spec.Service.Timeout != "" {
-			timeout := v1.Duration(canary.Spec.Service.Timeout)
-			hrClone.Spec.Rules[1].Timeouts = &v1.HTTPRouteTimeouts{
-				Request: &timeout,
-			}
+		if canary.Spec.Service.Timeout != "" || canary.Spec.Service.BackendTimeout != "" {
+			hrClone.Spec.Rules[1].Timeouts = makeHTTPRouteTimeouts(canary)
 		}
 	}
 
@@ -711,6 +699,19 @@ func (gwr *GatewayAPIRouter) mapRouteMatches(requestMatches []istiov1beta1.HTTPM
 	return matches, nil
 }
 
+func makeHTTPRouteTimeouts(canary *flaggerv1.Canary) *v1.HTTPRouteTimeouts {
+	timeouts := &v1.HTTPRouteTimeouts{}
+	if canary.Spec.Service.Timeout != "" {
+		timeout := v1.Duration(canary.Spec.Service.Timeout)
+		timeouts.Request = &timeout
+	}
+	if canary.Spec.Service.BackendTimeout != "" {
+		backendTimeout := v1.Duration(canary.Spec.Service.BackendTimeout)
+		timeouts.BackendRequest = &backendTimeout
+	}
+	return timeouts
+}
+
 func (gwr *GatewayAPIRouter) makeBackendRef(svcName string, weight, port int32) v1.BackendRef {
 	return v1.BackendRef{
 		BackendObjectReference: v1.BackendObjectReference{

pkg/router/gateway_api_test.go

@@ -61,6 +61,7 @@ func TestGatewayAPIRouter_Reconcile(t *testing.T) {
 
 	timeout := routeRules[0].Timeouts
 	assert.Equal(t, string(*timeout.Request), canary.Spec.Service.Timeout)
+	assert.Equal(t, string(*timeout.BackendRequest), canary.Spec.Service.BackendTimeout)
 
 	// assert that http route annotations injected by the networking controller is preserved.
 	httpRoute.Annotations["foo"] = "bar"

pkg/router/router_test.go

@@ -593,7 +593,8 @@ func newTestGatewayAPICanary() *flaggerv1.Canary {
 						Name: "podinfo",
 					},
 				},
-				Timeout: "10s",
+				Timeout:        "10s",
+				BackendTimeout: "5s",
 			},
 			Analysis: &flaggerv1.CanaryAnalysis{
 				Threshold:  10,