etcd/server/etcdserver/api/v3rpc/interceptor.go
Piotr Tabor 9e1abbab6e Fix goimports in all existing files. Execution of ./scripts/fix.sh
Signed-off-by: Piotr Tabor <ptab@google.com>
2022-12-29 09:41:31 +01:00

353 lines
10 KiB
Go

// Copyright 2016 The etcd 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 v3rpc
import (
"context"
"sync"
"time"
"unicode/utf8"
"go.etcd.io/etcd/api/v3/v3rpc/rpctypes"
"go.etcd.io/etcd/client/pkg/v3/types"
"go.etcd.io/etcd/server/v3/etcdserver"
"go.etcd.io/etcd/server/v3/etcdserver/api"
"go.etcd.io/raft/v3"
"go.uber.org/zap"
"google.golang.org/grpc"
"google.golang.org/grpc/metadata"
"google.golang.org/grpc/peer"
pb "go.etcd.io/etcd/api/v3/etcdserverpb"
)
const (
maxNoLeaderCnt = 3
snapshotMethod = "/etcdserverpb.Maintenance/Snapshot"
)
type streamsMap struct {
mu sync.Mutex
streams map[grpc.ServerStream]struct{}
}
func newUnaryInterceptor(s *etcdserver.EtcdServer) grpc.UnaryServerInterceptor {
return func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
if !api.IsCapabilityEnabled(api.V3rpcCapability) {
return nil, rpctypes.ErrGRPCNotCapable
}
if s.IsMemberExist(s.MemberId()) && s.IsLearner() && !isRPCSupportedForLearner(req) {
return nil, rpctypes.ErrGRPCNotSupportedForLearner
}
md, ok := metadata.FromIncomingContext(ctx)
if ok {
ver, vs := "unknown", md.Get(rpctypes.MetadataClientAPIVersionKey)
if len(vs) > 0 {
ver = vs[0]
}
if !utf8.ValidString(ver) {
return nil, rpctypes.ErrGRPCInvalidClientAPIVersion
}
clientRequests.WithLabelValues("unary", ver).Inc()
if ks := md[rpctypes.MetadataRequireLeaderKey]; len(ks) > 0 && ks[0] == rpctypes.MetadataHasLeader {
if s.Leader() == types.ID(raft.None) {
return nil, rpctypes.ErrGRPCNoLeader
}
}
}
return handler(ctx, req)
}
}
func newLogUnaryInterceptor(s *etcdserver.EtcdServer) grpc.UnaryServerInterceptor {
return func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
startTime := time.Now()
resp, err := handler(ctx, req)
lg := s.Logger()
if lg != nil { // acquire stats if debug level is enabled or RequestInfo is expensive
defer logUnaryRequestStats(ctx, lg, s.Cfg.WarningUnaryRequestDuration, info, startTime, req, resp)
}
return resp, err
}
}
func logUnaryRequestStats(ctx context.Context, lg *zap.Logger, warnLatency time.Duration, info *grpc.UnaryServerInfo, startTime time.Time, req interface{}, resp interface{}) {
duration := time.Since(startTime)
var enabledDebugLevel, expensiveRequest bool
if lg.Core().Enabled(zap.DebugLevel) {
enabledDebugLevel = true
}
if duration > warnLatency {
expensiveRequest = true
}
if !enabledDebugLevel && !expensiveRequest {
return
}
remote := "No remote client info."
peerInfo, ok := peer.FromContext(ctx)
if ok {
remote = peerInfo.Addr.String()
}
responseType := info.FullMethod
var reqCount, respCount int64
var reqSize, respSize int
var reqContent string
switch _resp := resp.(type) {
case *pb.RangeResponse:
_req, ok := req.(*pb.RangeRequest)
if ok {
reqCount = 0
reqSize = _req.Size()
reqContent = _req.String()
}
if _resp != nil {
respCount = _resp.GetCount()
respSize = _resp.Size()
}
case *pb.PutResponse:
_req, ok := req.(*pb.PutRequest)
if ok {
reqCount = 1
reqSize = _req.Size()
reqContent = pb.NewLoggablePutRequest(_req).String()
// redact value field from request content, see PR #9821
}
if _resp != nil {
respCount = 0
respSize = _resp.Size()
}
case *pb.DeleteRangeResponse:
_req, ok := req.(*pb.DeleteRangeRequest)
if ok {
reqCount = 0
reqSize = _req.Size()
reqContent = _req.String()
}
if _resp != nil {
respCount = _resp.GetDeleted()
respSize = _resp.Size()
}
case *pb.TxnResponse:
_req, ok := req.(*pb.TxnRequest)
if ok && _resp != nil {
if _resp.GetSucceeded() { // determine the 'actual' count and size of request based on success or failure
reqCount = int64(len(_req.GetSuccess()))
reqSize = 0
for _, r := range _req.GetSuccess() {
reqSize += r.Size()
}
} else {
reqCount = int64(len(_req.GetFailure()))
reqSize = 0
for _, r := range _req.GetFailure() {
reqSize += r.Size()
}
}
reqContent = pb.NewLoggableTxnRequest(_req).String()
// redact value field from request content, see PR #9821
}
if _resp != nil {
respCount = 0
respSize = _resp.Size()
}
default:
reqCount = -1
reqSize = -1
respCount = -1
respSize = -1
}
if enabledDebugLevel {
logGenericRequestStats(lg, startTime, duration, remote, responseType, reqCount, reqSize, respCount, respSize, reqContent)
} else if expensiveRequest {
logExpensiveRequestStats(lg, startTime, duration, remote, responseType, reqCount, reqSize, respCount, respSize, reqContent)
}
}
func logGenericRequestStats(lg *zap.Logger, startTime time.Time, duration time.Duration, remote string, responseType string,
reqCount int64, reqSize int, respCount int64, respSize int, reqContent string) {
lg.Debug("request stats",
zap.Time("start time", startTime),
zap.Duration("time spent", duration),
zap.String("remote", remote),
zap.String("response type", responseType),
zap.Int64("request count", reqCount),
zap.Int("request size", reqSize),
zap.Int64("response count", respCount),
zap.Int("response size", respSize),
zap.String("request content", reqContent),
)
}
func logExpensiveRequestStats(lg *zap.Logger, startTime time.Time, duration time.Duration, remote string, responseType string,
reqCount int64, reqSize int, respCount int64, respSize int, reqContent string) {
lg.Warn("request stats",
zap.Time("start time", startTime),
zap.Duration("time spent", duration),
zap.String("remote", remote),
zap.String("response type", responseType),
zap.Int64("request count", reqCount),
zap.Int("request size", reqSize),
zap.Int64("response count", respCount),
zap.Int("response size", respSize),
zap.String("request content", reqContent),
)
}
func newStreamInterceptor(s *etcdserver.EtcdServer) grpc.StreamServerInterceptor {
smap := monitorLeader(s)
return func(srv interface{}, ss grpc.ServerStream, info *grpc.StreamServerInfo, handler grpc.StreamHandler) error {
if !api.IsCapabilityEnabled(api.V3rpcCapability) {
return rpctypes.ErrGRPCNotCapable
}
if s.IsMemberExist(s.MemberId()) && s.IsLearner() && info.FullMethod != snapshotMethod { // learner does not support stream RPC except Snapshot
return rpctypes.ErrGRPCNotSupportedForLearner
}
md, ok := metadata.FromIncomingContext(ss.Context())
if ok {
ver, vs := "unknown", md.Get(rpctypes.MetadataClientAPIVersionKey)
if len(vs) > 0 {
ver = vs[0]
}
if !utf8.ValidString(ver) {
return rpctypes.ErrGRPCInvalidClientAPIVersion
}
clientRequests.WithLabelValues("stream", ver).Inc()
if ks := md[rpctypes.MetadataRequireLeaderKey]; len(ks) > 0 && ks[0] == rpctypes.MetadataHasLeader {
if s.Leader() == types.ID(raft.None) {
return rpctypes.ErrGRPCNoLeader
}
ctx := newCancellableContext(ss.Context())
ss = serverStreamWithCtx{ctx: ctx, ServerStream: ss}
smap.mu.Lock()
smap.streams[ss] = struct{}{}
smap.mu.Unlock()
defer func() {
smap.mu.Lock()
delete(smap.streams, ss)
smap.mu.Unlock()
// TODO: investigate whether the reason for cancellation here is useful to know
ctx.Cancel(nil)
}()
}
}
return handler(srv, ss)
}
}
// cancellableContext wraps a context with new cancellable context that allows a
// specific cancellation error to be preserved and later retrieved using the
// Context.Err() function. This is so downstream context users can disambiguate
// the reason for the cancellation which could be from the client (for example)
// or from this interceptor code.
type cancellableContext struct {
context.Context
lock sync.RWMutex
cancel context.CancelFunc
cancelReason error
}
func newCancellableContext(parent context.Context) *cancellableContext {
ctx, cancel := context.WithCancel(parent)
return &cancellableContext{
Context: ctx,
cancel: cancel,
}
}
// Cancel stores the cancellation reason and then delegates to context.WithCancel
// against the parent context.
func (c *cancellableContext) Cancel(reason error) {
c.lock.Lock()
c.cancelReason = reason
c.lock.Unlock()
c.cancel()
}
// Err will return the preserved cancel reason error if present, and will
// otherwise return the underlying error from the parent context.
func (c *cancellableContext) Err() error {
c.lock.RLock()
defer c.lock.RUnlock()
if c.cancelReason != nil {
return c.cancelReason
}
return c.Context.Err()
}
type serverStreamWithCtx struct {
grpc.ServerStream
// ctx is used so that we can preserve a reason for cancellation.
ctx *cancellableContext
}
func (ssc serverStreamWithCtx) Context() context.Context { return ssc.ctx }
func monitorLeader(s *etcdserver.EtcdServer) *streamsMap {
smap := &streamsMap{
streams: make(map[grpc.ServerStream]struct{}),
}
s.GoAttach(func() {
election := time.Duration(s.Cfg.TickMs) * time.Duration(s.Cfg.ElectionTicks) * time.Millisecond
noLeaderCnt := 0
for {
select {
case <-s.StoppingNotify():
return
case <-time.After(election):
if s.Leader() == types.ID(raft.None) {
noLeaderCnt++
} else {
noLeaderCnt = 0
}
// We are more conservative on canceling existing streams. Reconnecting streams
// cost much more than just rejecting new requests. So we wait until the member
// cannot find a leader for maxNoLeaderCnt election timeouts to cancel existing streams.
if noLeaderCnt >= maxNoLeaderCnt {
smap.mu.Lock()
for ss := range smap.streams {
if ssWithCtx, ok := ss.(serverStreamWithCtx); ok {
ssWithCtx.ctx.Cancel(rpctypes.ErrGRPCNoLeader)
<-ss.Context().Done()
}
}
smap.streams = make(map[grpc.ServerStream]struct{})
smap.mu.Unlock()
}
}
}
})
return smap
}