Add ingress (#18)

ingress/kube/annotations/retry.go

@@ -0,0 +1,134 @@
+// Copyright (c) 2022 Alibaba Group Holding Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package annotations
+
+import (
+	"strings"
+
+	"github.com/gogo/protobuf/types"
+
+	networking "istio.io/api/networking/v1alpha3"
+	"istio.io/istio/pilot/pkg/util/sets"
+)
+
+const (
+	retryCount      = "proxy-next-upstream-tries"
+	perRetryTimeout = "proxy-next-upstream-timeout"
+	retryOn         = "proxy-next-upstream"
+
+	defaultRetryCount = 3
+	defaultRetryOn    = "5xx"
+	retryStatusCode   = "retriable-status-codes"
+)
+
+var (
+	_ Parser       = retry{}
+	_ RouteHandler = retry{}
+)
+
+type RetryConfig struct {
+	retryCount      int32
+	perRetryTimeout *types.Duration
+	retryOn         string
+}
+
+type retry struct{}
+
+func (r retry) Parse(annotations Annotations, config *Ingress, _ *GlobalContext) error {
+	if !needRetryConfig(annotations) {
+		return nil
+	}
+
+	retryConfig := &RetryConfig{
+		retryCount:      defaultRetryCount,
+		perRetryTimeout: &types.Duration{},
+		retryOn:         defaultRetryOn,
+	}
+	defer func() {
+		config.Retry = retryConfig
+	}()
+
+	if count, err := annotations.ParseIntASAP(retryCount); err == nil {
+		retryConfig.retryCount = int32(count)
+	}
+
+	if timeout, err := annotations.ParseIntASAP(perRetryTimeout); err == nil {
+		retryConfig.perRetryTimeout = &types.Duration{
+			Seconds: int64(timeout),
+		}
+	}
+
+	if retryOn, err := annotations.ParseStringASAP(retryOn); err == nil {
+		conditions := toSet(splitBySeparator(retryOn, ","))
+		if len(conditions) > 0 {
+			if conditions.Contains("off") {
+				retryConfig.retryCount = 0
+			} else {
+				var stringBuilder strings.Builder
+				// Convert error, timeout, invalid_header to 5xx
+				if conditions.Contains("error") ||
+					conditions.Contains("timeout") ||
+					conditions.Contains("invalid_header") {
+					stringBuilder.WriteString(defaultRetryOn + ",")
+				}
+				// Just use the raw.
+				if conditions.Contains("non_idempotent") {
+					stringBuilder.WriteString("non_idempotent,")
+				}
+				// Append the status codes.
+				statusCodes := convertStatusCodes(conditions)
+				if len(statusCodes) > 0 {
+					stringBuilder.WriteString(retryStatusCode + ",")
+					for _, code := range statusCodes {
+						stringBuilder.WriteString(code + ",")
+					}
+				}
+
+				retryConfig.retryOn = strings.TrimSuffix(stringBuilder.String(), ",")
+			}
+		}
+	}
+
+	return nil
+}
+
+func (r retry) ApplyRoute(route *networking.HTTPRoute, config *Ingress) {
+	retryConfig := config.Retry
+	if retryConfig == nil {
+		return
+	}
+
+	route.Retries = &networking.HTTPRetry{
+		Attempts:      retryConfig.retryCount,
+		PerTryTimeout: retryConfig.perRetryTimeout,
+		RetryOn:       retryConfig.retryOn,
+	}
+}
+
+func needRetryConfig(annotations Annotations) bool {
+	return annotations.HasASAP(retryCount) ||
+		annotations.HasASAP(perRetryTimeout) ||
+		annotations.HasASAP(retryOn)
+}
+
+func convertStatusCodes(set sets.Set) []string {
+	var result []string
+	for condition := range set {
+		if strings.HasPrefix(condition, "http_") {
+			result = append(result, strings.TrimPrefix(condition, "http_"))
+		}
+	}
+	return result
+}