| // Copyright Istio Authors |
| // |
| // 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 retry |
| |
| import ( |
| "net/http" |
| "strconv" |
| "strings" |
| ) |
| |
| import ( |
| route "github.com/envoyproxy/go-control-plane/envoy/config/route/v3" |
| previouspriorities "github.com/envoyproxy/go-control-plane/envoy/extensions/retry/priority/previous_priorities/v3" |
| wrappers "google.golang.org/protobuf/types/known/wrapperspb" |
| networking "istio.io/api/networking/v1alpha3" |
| ) |
| |
| import ( |
| "github.com/apache/dubbo-go-pixiu/pilot/pkg/networking/util" |
| xdsfilters "github.com/apache/dubbo-go-pixiu/pilot/pkg/xds/filters" |
| ) |
| |
| var defaultRetryPriorityTypedConfig = util.MessageToAny(buildPreviousPrioritiesConfig()) |
| |
| // DefaultPolicy gets a copy of the default retry policy. |
| func DefaultPolicy() *route.RetryPolicy { |
| policy := route.RetryPolicy{ |
| NumRetries: &wrappers.UInt32Value{Value: 2}, |
| RetryOn: "connect-failure,refused-stream,unavailable,cancelled,retriable-status-codes", |
| RetriableStatusCodes: []uint32{http.StatusServiceUnavailable}, |
| RetryHostPredicate: []*route.RetryPolicy_RetryHostPredicate{ |
| // to configure retries to prefer hosts that haven’t been attempted already, |
| // the builtin `envoy.retry_host_predicates.previous_hosts` predicate can be used. |
| xdsfilters.RetryPreviousHosts, |
| }, |
| // TODO: allow this to be configured via API. |
| HostSelectionRetryMaxAttempts: 5, |
| } |
| return &policy |
| } |
| |
| // ConvertPolicy converts the given Istio retry policy to an Envoy policy. |
| // |
| // If in is nil, DefaultPolicy is returned. |
| // |
| // If in.Attempts == 0, returns nil. |
| // |
| // Otherwise, the returned policy is DefaultPolicy with the following overrides: |
| // |
| // - NumRetries: set from in.Attempts |
| // |
| // - RetryOn, RetriableStatusCodes: set from in.RetryOn (if specified). RetriableStatusCodes |
| // is appended when encountering parts that are valid HTTP status codes. |
| // |
| // - PerTryTimeout: set from in.PerTryTimeout (if specified) |
| func ConvertPolicy(in *networking.HTTPRetry) *route.RetryPolicy { |
| if in == nil { |
| // No policy was set, use a default. |
| return DefaultPolicy() |
| } |
| |
| if in.Attempts <= 0 { |
| // Configuration is explicitly disabling the retry policy. |
| return nil |
| } |
| |
| // A policy was specified. Start with the default and override with user-provided fields where appropriate. |
| out := DefaultPolicy() |
| out.NumRetries = &wrappers.UInt32Value{Value: uint32(in.Attempts)} |
| |
| if in.RetryOn != "" { |
| // Allow the incoming configuration to specify both Envoy RetryOn and RetriableStatusCodes. Any integers are |
| // assumed to be status codes. |
| out.RetryOn, out.RetriableStatusCodes = parseRetryOn(in.RetryOn) |
| // If user has just specified HTTP status codes in retryOn but have not specified "retriable-status-codes", let us add it. |
| if len(out.RetriableStatusCodes) > 0 && !strings.Contains(out.RetryOn, "retriable-status-codes") { |
| out.RetryOn += ",retriable-status-codes" |
| } |
| } |
| |
| if in.PerTryTimeout != nil { |
| out.PerTryTimeout = in.PerTryTimeout |
| } |
| |
| if in.RetryRemoteLocalities != nil && in.RetryRemoteLocalities.GetValue() { |
| out.RetryPriority = &route.RetryPolicy_RetryPriority{ |
| Name: "envoy.retry_priorities.previous_priorities", |
| ConfigType: &route.RetryPolicy_RetryPriority_TypedConfig{ |
| TypedConfig: defaultRetryPriorityTypedConfig, |
| }, |
| } |
| } |
| |
| return out |
| } |
| |
| func parseRetryOn(retryOn string) (string, []uint32) { |
| codes := make([]uint32, 0) |
| tojoin := make([]string, 0) |
| |
| parts := strings.Split(retryOn, ",") |
| for _, part := range parts { |
| part = strings.TrimSpace(part) |
| if part == "" { |
| continue |
| } |
| |
| // Try converting it to an integer to see if it's a valid HTTP status code. |
| i, err := strconv.Atoi(part) |
| |
| if err == nil && http.StatusText(i) != "" { |
| codes = append(codes, uint32(i)) |
| } else { |
| tojoin = append(tojoin, part) |
| } |
| } |
| |
| return strings.Join(tojoin, ","), codes |
| } |
| |
| // buildPreviousPrioritiesConfig builds a PreviousPrioritiesConfig with a default |
| // value for UpdateFrequency which indicated how often to update the priority. |
| func buildPreviousPrioritiesConfig() *previouspriorities.PreviousPrioritiesConfig { |
| return &previouspriorities.PreviousPrioritiesConfig{ |
| UpdateFrequency: int32(2), |
| } |
| } |