cloudflared-mirror/vendor/google.golang.org/grpc/server.go

2184 lines
68 KiB
Go

/*
*
* Copyright 2014 gRPC 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 grpc
import (
"context"
"errors"
"fmt"
"io"
"math"
"net"
"net/http"
"reflect"
"runtime"
"strings"
"sync"
"sync/atomic"
"time"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/credentials"
"google.golang.org/grpc/encoding"
"google.golang.org/grpc/encoding/proto"
"google.golang.org/grpc/grpclog"
"google.golang.org/grpc/internal"
"google.golang.org/grpc/internal/binarylog"
"google.golang.org/grpc/internal/channelz"
"google.golang.org/grpc/internal/grpcsync"
"google.golang.org/grpc/internal/grpcutil"
"google.golang.org/grpc/internal/transport"
"google.golang.org/grpc/keepalive"
"google.golang.org/grpc/metadata"
"google.golang.org/grpc/peer"
"google.golang.org/grpc/stats"
"google.golang.org/grpc/status"
"google.golang.org/grpc/tap"
)
const (
defaultServerMaxReceiveMessageSize = 1024 * 1024 * 4
defaultServerMaxSendMessageSize = math.MaxInt32
// Server transports are tracked in a map which is keyed on listener
// address. For regular gRPC traffic, connections are accepted in Serve()
// through a call to Accept(), and we use the actual listener address as key
// when we add it to the map. But for connections received through
// ServeHTTP(), we do not have a listener and hence use this dummy value.
listenerAddressForServeHTTP = "listenerAddressForServeHTTP"
)
func init() {
internal.GetServerCredentials = func(srv *Server) credentials.TransportCredentials {
return srv.opts.creds
}
internal.IsRegisteredMethod = func(srv *Server, method string) bool {
return srv.isRegisteredMethod(method)
}
internal.ServerFromContext = serverFromContext
internal.AddGlobalServerOptions = func(opt ...ServerOption) {
globalServerOptions = append(globalServerOptions, opt...)
}
internal.ClearGlobalServerOptions = func() {
globalServerOptions = nil
}
internal.BinaryLogger = binaryLogger
internal.JoinServerOptions = newJoinServerOption
internal.RecvBufferPool = recvBufferPool
}
var statusOK = status.New(codes.OK, "")
var logger = grpclog.Component("core")
type methodHandler func(srv any, ctx context.Context, dec func(any) error, interceptor UnaryServerInterceptor) (any, error)
// MethodDesc represents an RPC service's method specification.
type MethodDesc struct {
MethodName string
Handler methodHandler
}
// ServiceDesc represents an RPC service's specification.
type ServiceDesc struct {
ServiceName string
// The pointer to the service interface. Used to check whether the user
// provided implementation satisfies the interface requirements.
HandlerType any
Methods []MethodDesc
Streams []StreamDesc
Metadata any
}
// serviceInfo wraps information about a service. It is very similar to
// ServiceDesc and is constructed from it for internal purposes.
type serviceInfo struct {
// Contains the implementation for the methods in this service.
serviceImpl any
methods map[string]*MethodDesc
streams map[string]*StreamDesc
mdata any
}
// Server is a gRPC server to serve RPC requests.
type Server struct {
opts serverOptions
mu sync.Mutex // guards following
lis map[net.Listener]bool
// conns contains all active server transports. It is a map keyed on a
// listener address with the value being the set of active transports
// belonging to that listener.
conns map[string]map[transport.ServerTransport]bool
serve bool
drain bool
cv *sync.Cond // signaled when connections close for GracefulStop
services map[string]*serviceInfo // service name -> service info
events traceEventLog
quit *grpcsync.Event
done *grpcsync.Event
channelzRemoveOnce sync.Once
serveWG sync.WaitGroup // counts active Serve goroutines for Stop/GracefulStop
handlersWG sync.WaitGroup // counts active method handler goroutines
channelz *channelz.Server
serverWorkerChannel chan func()
serverWorkerChannelClose func()
}
type serverOptions struct {
creds credentials.TransportCredentials
codec baseCodec
cp Compressor
dc Decompressor
unaryInt UnaryServerInterceptor
streamInt StreamServerInterceptor
chainUnaryInts []UnaryServerInterceptor
chainStreamInts []StreamServerInterceptor
binaryLogger binarylog.Logger
inTapHandle tap.ServerInHandle
statsHandlers []stats.Handler
maxConcurrentStreams uint32
maxReceiveMessageSize int
maxSendMessageSize int
unknownStreamDesc *StreamDesc
keepaliveParams keepalive.ServerParameters
keepalivePolicy keepalive.EnforcementPolicy
initialWindowSize int32
initialConnWindowSize int32
writeBufferSize int
readBufferSize int
sharedWriteBuffer bool
connectionTimeout time.Duration
maxHeaderListSize *uint32
headerTableSize *uint32
numServerWorkers uint32
recvBufferPool SharedBufferPool
waitForHandlers bool
}
var defaultServerOptions = serverOptions{
maxConcurrentStreams: math.MaxUint32,
maxReceiveMessageSize: defaultServerMaxReceiveMessageSize,
maxSendMessageSize: defaultServerMaxSendMessageSize,
connectionTimeout: 120 * time.Second,
writeBufferSize: defaultWriteBufSize,
readBufferSize: defaultReadBufSize,
recvBufferPool: nopBufferPool{},
}
var globalServerOptions []ServerOption
// A ServerOption sets options such as credentials, codec and keepalive parameters, etc.
type ServerOption interface {
apply(*serverOptions)
}
// EmptyServerOption does not alter the server configuration. It can be embedded
// in another structure to build custom server options.
//
// # Experimental
//
// Notice: This type is EXPERIMENTAL and may be changed or removed in a
// later release.
type EmptyServerOption struct{}
func (EmptyServerOption) apply(*serverOptions) {}
// funcServerOption wraps a function that modifies serverOptions into an
// implementation of the ServerOption interface.
type funcServerOption struct {
f func(*serverOptions)
}
func (fdo *funcServerOption) apply(do *serverOptions) {
fdo.f(do)
}
func newFuncServerOption(f func(*serverOptions)) *funcServerOption {
return &funcServerOption{
f: f,
}
}
// joinServerOption provides a way to combine arbitrary number of server
// options into one.
type joinServerOption struct {
opts []ServerOption
}
func (mdo *joinServerOption) apply(do *serverOptions) {
for _, opt := range mdo.opts {
opt.apply(do)
}
}
func newJoinServerOption(opts ...ServerOption) ServerOption {
return &joinServerOption{opts: opts}
}
// SharedWriteBuffer allows reusing per-connection transport write buffer.
// If this option is set to true every connection will release the buffer after
// flushing the data on the wire.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func SharedWriteBuffer(val bool) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.sharedWriteBuffer = val
})
}
// WriteBufferSize determines how much data can be batched before doing a write
// on the wire. The default value for this buffer is 32KB. Zero or negative
// values will disable the write buffer such that each write will be on underlying
// connection. Note: A Send call may not directly translate to a write.
func WriteBufferSize(s int) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.writeBufferSize = s
})
}
// ReadBufferSize lets you set the size of read buffer, this determines how much
// data can be read at most for one read syscall. The default value for this
// buffer is 32KB. Zero or negative values will disable read buffer for a
// connection so data framer can access the underlying conn directly.
func ReadBufferSize(s int) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.readBufferSize = s
})
}
// InitialWindowSize returns a ServerOption that sets window size for stream.
// The lower bound for window size is 64K and any value smaller than that will be ignored.
func InitialWindowSize(s int32) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.initialWindowSize = s
})
}
// InitialConnWindowSize returns a ServerOption that sets window size for a connection.
// The lower bound for window size is 64K and any value smaller than that will be ignored.
func InitialConnWindowSize(s int32) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.initialConnWindowSize = s
})
}
// KeepaliveParams returns a ServerOption that sets keepalive and max-age parameters for the server.
func KeepaliveParams(kp keepalive.ServerParameters) ServerOption {
if kp.Time > 0 && kp.Time < internal.KeepaliveMinServerPingTime {
logger.Warning("Adjusting keepalive ping interval to minimum period of 1s")
kp.Time = internal.KeepaliveMinServerPingTime
}
return newFuncServerOption(func(o *serverOptions) {
o.keepaliveParams = kp
})
}
// KeepaliveEnforcementPolicy returns a ServerOption that sets keepalive enforcement policy for the server.
func KeepaliveEnforcementPolicy(kep keepalive.EnforcementPolicy) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.keepalivePolicy = kep
})
}
// CustomCodec returns a ServerOption that sets a codec for message marshaling and unmarshaling.
//
// This will override any lookups by content-subtype for Codecs registered with RegisterCodec.
//
// Deprecated: register codecs using encoding.RegisterCodec. The server will
// automatically use registered codecs based on the incoming requests' headers.
// See also
// https://github.com/grpc/grpc-go/blob/master/Documentation/encoding.md#using-a-codec.
// Will be supported throughout 1.x.
func CustomCodec(codec Codec) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.codec = codec
})
}
// ForceServerCodec returns a ServerOption that sets a codec for message
// marshaling and unmarshaling.
//
// This will override any lookups by content-subtype for Codecs registered
// with RegisterCodec.
//
// See Content-Type on
// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for
// more details. Also see the documentation on RegisterCodec and
// CallContentSubtype for more details on the interaction between encoding.Codec
// and content-subtype.
//
// This function is provided for advanced users; prefer to register codecs
// using encoding.RegisterCodec.
// The server will automatically use registered codecs based on the incoming
// requests' headers. See also
// https://github.com/grpc/grpc-go/blob/master/Documentation/encoding.md#using-a-codec.
// Will be supported throughout 1.x.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func ForceServerCodec(codec encoding.Codec) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.codec = codec
})
}
// RPCCompressor returns a ServerOption that sets a compressor for outbound
// messages. For backward compatibility, all outbound messages will be sent
// using this compressor, regardless of incoming message compression. By
// default, server messages will be sent using the same compressor with which
// request messages were sent.
//
// Deprecated: use encoding.RegisterCompressor instead. Will be supported
// throughout 1.x.
func RPCCompressor(cp Compressor) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.cp = cp
})
}
// RPCDecompressor returns a ServerOption that sets a decompressor for inbound
// messages. It has higher priority than decompressors registered via
// encoding.RegisterCompressor.
//
// Deprecated: use encoding.RegisterCompressor instead. Will be supported
// throughout 1.x.
func RPCDecompressor(dc Decompressor) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.dc = dc
})
}
// MaxMsgSize returns a ServerOption to set the max message size in bytes the server can receive.
// If this is not set, gRPC uses the default limit.
//
// Deprecated: use MaxRecvMsgSize instead. Will be supported throughout 1.x.
func MaxMsgSize(m int) ServerOption {
return MaxRecvMsgSize(m)
}
// MaxRecvMsgSize returns a ServerOption to set the max message size in bytes the server can receive.
// If this is not set, gRPC uses the default 4MB.
func MaxRecvMsgSize(m int) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.maxReceiveMessageSize = m
})
}
// MaxSendMsgSize returns a ServerOption to set the max message size in bytes the server can send.
// If this is not set, gRPC uses the default `math.MaxInt32`.
func MaxSendMsgSize(m int) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.maxSendMessageSize = m
})
}
// MaxConcurrentStreams returns a ServerOption that will apply a limit on the number
// of concurrent streams to each ServerTransport.
func MaxConcurrentStreams(n uint32) ServerOption {
if n == 0 {
n = math.MaxUint32
}
return newFuncServerOption(func(o *serverOptions) {
o.maxConcurrentStreams = n
})
}
// Creds returns a ServerOption that sets credentials for server connections.
func Creds(c credentials.TransportCredentials) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.creds = c
})
}
// UnaryInterceptor returns a ServerOption that sets the UnaryServerInterceptor for the
// server. Only one unary interceptor can be installed. The construction of multiple
// interceptors (e.g., chaining) can be implemented at the caller.
func UnaryInterceptor(i UnaryServerInterceptor) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
if o.unaryInt != nil {
panic("The unary server interceptor was already set and may not be reset.")
}
o.unaryInt = i
})
}
// ChainUnaryInterceptor returns a ServerOption that specifies the chained interceptor
// for unary RPCs. The first interceptor will be the outer most,
// while the last interceptor will be the inner most wrapper around the real call.
// All unary interceptors added by this method will be chained.
func ChainUnaryInterceptor(interceptors ...UnaryServerInterceptor) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.chainUnaryInts = append(o.chainUnaryInts, interceptors...)
})
}
// StreamInterceptor returns a ServerOption that sets the StreamServerInterceptor for the
// server. Only one stream interceptor can be installed.
func StreamInterceptor(i StreamServerInterceptor) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
if o.streamInt != nil {
panic("The stream server interceptor was already set and may not be reset.")
}
o.streamInt = i
})
}
// ChainStreamInterceptor returns a ServerOption that specifies the chained interceptor
// for streaming RPCs. The first interceptor will be the outer most,
// while the last interceptor will be the inner most wrapper around the real call.
// All stream interceptors added by this method will be chained.
func ChainStreamInterceptor(interceptors ...StreamServerInterceptor) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.chainStreamInts = append(o.chainStreamInts, interceptors...)
})
}
// InTapHandle returns a ServerOption that sets the tap handle for all the server
// transport to be created. Only one can be installed.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func InTapHandle(h tap.ServerInHandle) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
if o.inTapHandle != nil {
panic("The tap handle was already set and may not be reset.")
}
o.inTapHandle = h
})
}
// StatsHandler returns a ServerOption that sets the stats handler for the server.
func StatsHandler(h stats.Handler) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
if h == nil {
logger.Error("ignoring nil parameter in grpc.StatsHandler ServerOption")
// Do not allow a nil stats handler, which would otherwise cause
// panics.
return
}
o.statsHandlers = append(o.statsHandlers, h)
})
}
// binaryLogger returns a ServerOption that can set the binary logger for the
// server.
func binaryLogger(bl binarylog.Logger) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.binaryLogger = bl
})
}
// UnknownServiceHandler returns a ServerOption that allows for adding a custom
// unknown service handler. The provided method is a bidi-streaming RPC service
// handler that will be invoked instead of returning the "unimplemented" gRPC
// error whenever a request is received for an unregistered service or method.
// The handling function and stream interceptor (if set) have full access to
// the ServerStream, including its Context.
func UnknownServiceHandler(streamHandler StreamHandler) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.unknownStreamDesc = &StreamDesc{
StreamName: "unknown_service_handler",
Handler: streamHandler,
// We need to assume that the users of the streamHandler will want to use both.
ClientStreams: true,
ServerStreams: true,
}
})
}
// ConnectionTimeout returns a ServerOption that sets the timeout for
// connection establishment (up to and including HTTP/2 handshaking) for all
// new connections. If this is not set, the default is 120 seconds. A zero or
// negative value will result in an immediate timeout.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func ConnectionTimeout(d time.Duration) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.connectionTimeout = d
})
}
// MaxHeaderListSize returns a ServerOption that sets the max (uncompressed) size
// of header list that the server is prepared to accept.
func MaxHeaderListSize(s uint32) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.maxHeaderListSize = &s
})
}
// HeaderTableSize returns a ServerOption that sets the size of dynamic
// header table for stream.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func HeaderTableSize(s uint32) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.headerTableSize = &s
})
}
// NumStreamWorkers returns a ServerOption that sets the number of worker
// goroutines that should be used to process incoming streams. Setting this to
// zero (default) will disable workers and spawn a new goroutine for each
// stream.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func NumStreamWorkers(numServerWorkers uint32) ServerOption {
// TODO: If/when this API gets stabilized (i.e. stream workers become the
// only way streams are processed), change the behavior of the zero value to
// a sane default. Preliminary experiments suggest that a value equal to the
// number of CPUs available is most performant; requires thorough testing.
return newFuncServerOption(func(o *serverOptions) {
o.numServerWorkers = numServerWorkers
})
}
// WaitForHandlers cause Stop to wait until all outstanding method handlers have
// exited before returning. If false, Stop will return as soon as all
// connections have closed, but method handlers may still be running. By
// default, Stop does not wait for method handlers to return.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func WaitForHandlers(w bool) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.waitForHandlers = w
})
}
// RecvBufferPool returns a ServerOption that configures the server
// to use the provided shared buffer pool for parsing incoming messages. Depending
// on the application's workload, this could result in reduced memory allocation.
//
// If you are unsure about how to implement a memory pool but want to utilize one,
// begin with grpc.NewSharedBufferPool.
//
// Note: The shared buffer pool feature will not be active if any of the following
// options are used: StatsHandler, EnableTracing, or binary logging. In such
// cases, the shared buffer pool will be ignored.
//
// Deprecated: use experimental.WithRecvBufferPool instead. Will be deleted in
// v1.60.0 or later.
func RecvBufferPool(bufferPool SharedBufferPool) ServerOption {
return recvBufferPool(bufferPool)
}
func recvBufferPool(bufferPool SharedBufferPool) ServerOption {
return newFuncServerOption(func(o *serverOptions) {
o.recvBufferPool = bufferPool
})
}
// serverWorkerResetThreshold defines how often the stack must be reset. Every
// N requests, by spawning a new goroutine in its place, a worker can reset its
// stack so that large stacks don't live in memory forever. 2^16 should allow
// each goroutine stack to live for at least a few seconds in a typical
// workload (assuming a QPS of a few thousand requests/sec).
const serverWorkerResetThreshold = 1 << 16
// serverWorkers blocks on a *transport.Stream channel forever and waits for
// data to be fed by serveStreams. This allows multiple requests to be
// processed by the same goroutine, removing the need for expensive stack
// re-allocations (see the runtime.morestack problem [1]).
//
// [1] https://github.com/golang/go/issues/18138
func (s *Server) serverWorker() {
for completed := 0; completed < serverWorkerResetThreshold; completed++ {
f, ok := <-s.serverWorkerChannel
if !ok {
return
}
f()
}
go s.serverWorker()
}
// initServerWorkers creates worker goroutines and a channel to process incoming
// connections to reduce the time spent overall on runtime.morestack.
func (s *Server) initServerWorkers() {
s.serverWorkerChannel = make(chan func())
s.serverWorkerChannelClose = grpcsync.OnceFunc(func() {
close(s.serverWorkerChannel)
})
for i := uint32(0); i < s.opts.numServerWorkers; i++ {
go s.serverWorker()
}
}
// NewServer creates a gRPC server which has no service registered and has not
// started to accept requests yet.
func NewServer(opt ...ServerOption) *Server {
opts := defaultServerOptions
for _, o := range globalServerOptions {
o.apply(&opts)
}
for _, o := range opt {
o.apply(&opts)
}
s := &Server{
lis: make(map[net.Listener]bool),
opts: opts,
conns: make(map[string]map[transport.ServerTransport]bool),
services: make(map[string]*serviceInfo),
quit: grpcsync.NewEvent(),
done: grpcsync.NewEvent(),
channelz: channelz.RegisterServer(""),
}
chainUnaryServerInterceptors(s)
chainStreamServerInterceptors(s)
s.cv = sync.NewCond(&s.mu)
if EnableTracing {
_, file, line, _ := runtime.Caller(1)
s.events = newTraceEventLog("grpc.Server", fmt.Sprintf("%s:%d", file, line))
}
if s.opts.numServerWorkers > 0 {
s.initServerWorkers()
}
channelz.Info(logger, s.channelz, "Server created")
return s
}
// printf records an event in s's event log, unless s has been stopped.
// REQUIRES s.mu is held.
func (s *Server) printf(format string, a ...any) {
if s.events != nil {
s.events.Printf(format, a...)
}
}
// errorf records an error in s's event log, unless s has been stopped.
// REQUIRES s.mu is held.
func (s *Server) errorf(format string, a ...any) {
if s.events != nil {
s.events.Errorf(format, a...)
}
}
// ServiceRegistrar wraps a single method that supports service registration. It
// enables users to pass concrete types other than grpc.Server to the service
// registration methods exported by the IDL generated code.
type ServiceRegistrar interface {
// RegisterService registers a service and its implementation to the
// concrete type implementing this interface. It may not be called
// once the server has started serving.
// desc describes the service and its methods and handlers. impl is the
// service implementation which is passed to the method handlers.
RegisterService(desc *ServiceDesc, impl any)
}
// RegisterService registers a service and its implementation to the gRPC
// server. It is called from the IDL generated code. This must be called before
// invoking Serve. If ss is non-nil (for legacy code), its type is checked to
// ensure it implements sd.HandlerType.
func (s *Server) RegisterService(sd *ServiceDesc, ss any) {
if ss != nil {
ht := reflect.TypeOf(sd.HandlerType).Elem()
st := reflect.TypeOf(ss)
if !st.Implements(ht) {
logger.Fatalf("grpc: Server.RegisterService found the handler of type %v that does not satisfy %v", st, ht)
}
}
s.register(sd, ss)
}
func (s *Server) register(sd *ServiceDesc, ss any) {
s.mu.Lock()
defer s.mu.Unlock()
s.printf("RegisterService(%q)", sd.ServiceName)
if s.serve {
logger.Fatalf("grpc: Server.RegisterService after Server.Serve for %q", sd.ServiceName)
}
if _, ok := s.services[sd.ServiceName]; ok {
logger.Fatalf("grpc: Server.RegisterService found duplicate service registration for %q", sd.ServiceName)
}
info := &serviceInfo{
serviceImpl: ss,
methods: make(map[string]*MethodDesc),
streams: make(map[string]*StreamDesc),
mdata: sd.Metadata,
}
for i := range sd.Methods {
d := &sd.Methods[i]
info.methods[d.MethodName] = d
}
for i := range sd.Streams {
d := &sd.Streams[i]
info.streams[d.StreamName] = d
}
s.services[sd.ServiceName] = info
}
// MethodInfo contains the information of an RPC including its method name and type.
type MethodInfo struct {
// Name is the method name only, without the service name or package name.
Name string
// IsClientStream indicates whether the RPC is a client streaming RPC.
IsClientStream bool
// IsServerStream indicates whether the RPC is a server streaming RPC.
IsServerStream bool
}
// ServiceInfo contains unary RPC method info, streaming RPC method info and metadata for a service.
type ServiceInfo struct {
Methods []MethodInfo
// Metadata is the metadata specified in ServiceDesc when registering service.
Metadata any
}
// GetServiceInfo returns a map from service names to ServiceInfo.
// Service names include the package names, in the form of <package>.<service>.
func (s *Server) GetServiceInfo() map[string]ServiceInfo {
ret := make(map[string]ServiceInfo)
for n, srv := range s.services {
methods := make([]MethodInfo, 0, len(srv.methods)+len(srv.streams))
for m := range srv.methods {
methods = append(methods, MethodInfo{
Name: m,
IsClientStream: false,
IsServerStream: false,
})
}
for m, d := range srv.streams {
methods = append(methods, MethodInfo{
Name: m,
IsClientStream: d.ClientStreams,
IsServerStream: d.ServerStreams,
})
}
ret[n] = ServiceInfo{
Methods: methods,
Metadata: srv.mdata,
}
}
return ret
}
// ErrServerStopped indicates that the operation is now illegal because of
// the server being stopped.
var ErrServerStopped = errors.New("grpc: the server has been stopped")
type listenSocket struct {
net.Listener
channelz *channelz.Socket
}
func (l *listenSocket) Close() error {
err := l.Listener.Close()
channelz.RemoveEntry(l.channelz.ID)
channelz.Info(logger, l.channelz, "ListenSocket deleted")
return err
}
// Serve accepts incoming connections on the listener lis, creating a new
// ServerTransport and service goroutine for each. The service goroutines
// read gRPC requests and then call the registered handlers to reply to them.
// Serve returns when lis.Accept fails with fatal errors. lis will be closed when
// this method returns.
// Serve will return a non-nil error unless Stop or GracefulStop is called.
//
// Note: All supported releases of Go (as of December 2023) override the OS
// defaults for TCP keepalive time and interval to 15s. To enable TCP keepalive
// with OS defaults for keepalive time and interval, callers need to do the
// following two things:
// - pass a net.Listener created by calling the Listen method on a
// net.ListenConfig with the `KeepAlive` field set to a negative value. This
// will result in the Go standard library not overriding OS defaults for TCP
// keepalive interval and time. But this will also result in the Go standard
// library not enabling TCP keepalives by default.
// - override the Accept method on the passed in net.Listener and set the
// SO_KEEPALIVE socket option to enable TCP keepalives, with OS defaults.
func (s *Server) Serve(lis net.Listener) error {
s.mu.Lock()
s.printf("serving")
s.serve = true
if s.lis == nil {
// Serve called after Stop or GracefulStop.
s.mu.Unlock()
lis.Close()
return ErrServerStopped
}
s.serveWG.Add(1)
defer func() {
s.serveWG.Done()
if s.quit.HasFired() {
// Stop or GracefulStop called; block until done and return nil.
<-s.done.Done()
}
}()
ls := &listenSocket{
Listener: lis,
channelz: channelz.RegisterSocket(&channelz.Socket{
SocketType: channelz.SocketTypeListen,
Parent: s.channelz,
RefName: lis.Addr().String(),
LocalAddr: lis.Addr(),
SocketOptions: channelz.GetSocketOption(lis)},
),
}
s.lis[ls] = true
defer func() {
s.mu.Lock()
if s.lis != nil && s.lis[ls] {
ls.Close()
delete(s.lis, ls)
}
s.mu.Unlock()
}()
s.mu.Unlock()
channelz.Info(logger, ls.channelz, "ListenSocket created")
var tempDelay time.Duration // how long to sleep on accept failure
for {
rawConn, err := lis.Accept()
if err != nil {
if ne, ok := err.(interface {
Temporary() bool
}); ok && ne.Temporary() {
if tempDelay == 0 {
tempDelay = 5 * time.Millisecond
} else {
tempDelay *= 2
}
if max := 1 * time.Second; tempDelay > max {
tempDelay = max
}
s.mu.Lock()
s.printf("Accept error: %v; retrying in %v", err, tempDelay)
s.mu.Unlock()
timer := time.NewTimer(tempDelay)
select {
case <-timer.C:
case <-s.quit.Done():
timer.Stop()
return nil
}
continue
}
s.mu.Lock()
s.printf("done serving; Accept = %v", err)
s.mu.Unlock()
if s.quit.HasFired() {
return nil
}
return err
}
tempDelay = 0
// Start a new goroutine to deal with rawConn so we don't stall this Accept
// loop goroutine.
//
// Make sure we account for the goroutine so GracefulStop doesn't nil out
// s.conns before this conn can be added.
s.serveWG.Add(1)
go func() {
s.handleRawConn(lis.Addr().String(), rawConn)
s.serveWG.Done()
}()
}
}
// handleRawConn forks a goroutine to handle a just-accepted connection that
// has not had any I/O performed on it yet.
func (s *Server) handleRawConn(lisAddr string, rawConn net.Conn) {
if s.quit.HasFired() {
rawConn.Close()
return
}
rawConn.SetDeadline(time.Now().Add(s.opts.connectionTimeout))
// Finish handshaking (HTTP2)
st := s.newHTTP2Transport(rawConn)
rawConn.SetDeadline(time.Time{})
if st == nil {
return
}
if cc, ok := rawConn.(interface {
PassServerTransport(transport.ServerTransport)
}); ok {
cc.PassServerTransport(st)
}
if !s.addConn(lisAddr, st) {
return
}
go func() {
s.serveStreams(context.Background(), st, rawConn)
s.removeConn(lisAddr, st)
}()
}
// newHTTP2Transport sets up a http/2 transport (using the
// gRPC http2 server transport in transport/http2_server.go).
func (s *Server) newHTTP2Transport(c net.Conn) transport.ServerTransport {
config := &transport.ServerConfig{
MaxStreams: s.opts.maxConcurrentStreams,
ConnectionTimeout: s.opts.connectionTimeout,
Credentials: s.opts.creds,
InTapHandle: s.opts.inTapHandle,
StatsHandlers: s.opts.statsHandlers,
KeepaliveParams: s.opts.keepaliveParams,
KeepalivePolicy: s.opts.keepalivePolicy,
InitialWindowSize: s.opts.initialWindowSize,
InitialConnWindowSize: s.opts.initialConnWindowSize,
WriteBufferSize: s.opts.writeBufferSize,
ReadBufferSize: s.opts.readBufferSize,
SharedWriteBuffer: s.opts.sharedWriteBuffer,
ChannelzParent: s.channelz,
MaxHeaderListSize: s.opts.maxHeaderListSize,
HeaderTableSize: s.opts.headerTableSize,
}
st, err := transport.NewServerTransport(c, config)
if err != nil {
s.mu.Lock()
s.errorf("NewServerTransport(%q) failed: %v", c.RemoteAddr(), err)
s.mu.Unlock()
// ErrConnDispatched means that the connection was dispatched away from
// gRPC; those connections should be left open.
if err != credentials.ErrConnDispatched {
// Don't log on ErrConnDispatched and io.EOF to prevent log spam.
if err != io.EOF {
channelz.Info(logger, s.channelz, "grpc: Server.Serve failed to create ServerTransport: ", err)
}
c.Close()
}
return nil
}
return st
}
func (s *Server) serveStreams(ctx context.Context, st transport.ServerTransport, rawConn net.Conn) {
ctx = transport.SetConnection(ctx, rawConn)
ctx = peer.NewContext(ctx, st.Peer())
for _, sh := range s.opts.statsHandlers {
ctx = sh.TagConn(ctx, &stats.ConnTagInfo{
RemoteAddr: st.Peer().Addr,
LocalAddr: st.Peer().LocalAddr,
})
sh.HandleConn(ctx, &stats.ConnBegin{})
}
defer func() {
st.Close(errors.New("finished serving streams for the server transport"))
for _, sh := range s.opts.statsHandlers {
sh.HandleConn(ctx, &stats.ConnEnd{})
}
}()
streamQuota := newHandlerQuota(s.opts.maxConcurrentStreams)
st.HandleStreams(ctx, func(stream *transport.Stream) {
s.handlersWG.Add(1)
streamQuota.acquire()
f := func() {
defer streamQuota.release()
defer s.handlersWG.Done()
s.handleStream(st, stream)
}
if s.opts.numServerWorkers > 0 {
select {
case s.serverWorkerChannel <- f:
return
default:
// If all stream workers are busy, fallback to the default code path.
}
}
go f()
})
}
var _ http.Handler = (*Server)(nil)
// ServeHTTP implements the Go standard library's http.Handler
// interface by responding to the gRPC request r, by looking up
// the requested gRPC method in the gRPC server s.
//
// The provided HTTP request must have arrived on an HTTP/2
// connection. When using the Go standard library's server,
// practically this means that the Request must also have arrived
// over TLS.
//
// To share one port (such as 443 for https) between gRPC and an
// existing http.Handler, use a root http.Handler such as:
//
// if r.ProtoMajor == 2 && strings.HasPrefix(
// r.Header.Get("Content-Type"), "application/grpc") {
// grpcServer.ServeHTTP(w, r)
// } else {
// yourMux.ServeHTTP(w, r)
// }
//
// Note that ServeHTTP uses Go's HTTP/2 server implementation which is totally
// separate from grpc-go's HTTP/2 server. Performance and features may vary
// between the two paths. ServeHTTP does not support some gRPC features
// available through grpc-go's HTTP/2 server.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
st, err := transport.NewServerHandlerTransport(w, r, s.opts.statsHandlers)
if err != nil {
// Errors returned from transport.NewServerHandlerTransport have
// already been written to w.
return
}
if !s.addConn(listenerAddressForServeHTTP, st) {
return
}
defer s.removeConn(listenerAddressForServeHTTP, st)
s.serveStreams(r.Context(), st, nil)
}
func (s *Server) addConn(addr string, st transport.ServerTransport) bool {
s.mu.Lock()
defer s.mu.Unlock()
if s.conns == nil {
st.Close(errors.New("Server.addConn called when server has already been stopped"))
return false
}
if s.drain {
// Transport added after we drained our existing conns: drain it
// immediately.
st.Drain("")
}
if s.conns[addr] == nil {
// Create a map entry if this is the first connection on this listener.
s.conns[addr] = make(map[transport.ServerTransport]bool)
}
s.conns[addr][st] = true
return true
}
func (s *Server) removeConn(addr string, st transport.ServerTransport) {
s.mu.Lock()
defer s.mu.Unlock()
conns := s.conns[addr]
if conns != nil {
delete(conns, st)
if len(conns) == 0 {
// If the last connection for this address is being removed, also
// remove the map entry corresponding to the address. This is used
// in GracefulStop() when waiting for all connections to be closed.
delete(s.conns, addr)
}
s.cv.Broadcast()
}
}
func (s *Server) incrCallsStarted() {
s.channelz.ServerMetrics.CallsStarted.Add(1)
s.channelz.ServerMetrics.LastCallStartedTimestamp.Store(time.Now().UnixNano())
}
func (s *Server) incrCallsSucceeded() {
s.channelz.ServerMetrics.CallsSucceeded.Add(1)
}
func (s *Server) incrCallsFailed() {
s.channelz.ServerMetrics.CallsFailed.Add(1)
}
func (s *Server) sendResponse(ctx context.Context, t transport.ServerTransport, stream *transport.Stream, msg any, cp Compressor, opts *transport.Options, comp encoding.Compressor) error {
data, err := encode(s.getCodec(stream.ContentSubtype()), msg)
if err != nil {
channelz.Error(logger, s.channelz, "grpc: server failed to encode response: ", err)
return err
}
compData, err := compress(data, cp, comp)
if err != nil {
channelz.Error(logger, s.channelz, "grpc: server failed to compress response: ", err)
return err
}
hdr, payload := msgHeader(data, compData)
// TODO(dfawley): should we be checking len(data) instead?
if len(payload) > s.opts.maxSendMessageSize {
return status.Errorf(codes.ResourceExhausted, "grpc: trying to send message larger than max (%d vs. %d)", len(payload), s.opts.maxSendMessageSize)
}
err = t.Write(stream, hdr, payload, opts)
if err == nil {
for _, sh := range s.opts.statsHandlers {
sh.HandleRPC(ctx, outPayload(false, msg, data, payload, time.Now()))
}
}
return err
}
// chainUnaryServerInterceptors chains all unary server interceptors into one.
func chainUnaryServerInterceptors(s *Server) {
// Prepend opts.unaryInt to the chaining interceptors if it exists, since unaryInt will
// be executed before any other chained interceptors.
interceptors := s.opts.chainUnaryInts
if s.opts.unaryInt != nil {
interceptors = append([]UnaryServerInterceptor{s.opts.unaryInt}, s.opts.chainUnaryInts...)
}
var chainedInt UnaryServerInterceptor
if len(interceptors) == 0 {
chainedInt = nil
} else if len(interceptors) == 1 {
chainedInt = interceptors[0]
} else {
chainedInt = chainUnaryInterceptors(interceptors)
}
s.opts.unaryInt = chainedInt
}
func chainUnaryInterceptors(interceptors []UnaryServerInterceptor) UnaryServerInterceptor {
return func(ctx context.Context, req any, info *UnaryServerInfo, handler UnaryHandler) (any, error) {
return interceptors[0](ctx, req, info, getChainUnaryHandler(interceptors, 0, info, handler))
}
}
func getChainUnaryHandler(interceptors []UnaryServerInterceptor, curr int, info *UnaryServerInfo, finalHandler UnaryHandler) UnaryHandler {
if curr == len(interceptors)-1 {
return finalHandler
}
return func(ctx context.Context, req any) (any, error) {
return interceptors[curr+1](ctx, req, info, getChainUnaryHandler(interceptors, curr+1, info, finalHandler))
}
}
func (s *Server) processUnaryRPC(ctx context.Context, t transport.ServerTransport, stream *transport.Stream, info *serviceInfo, md *MethodDesc, trInfo *traceInfo) (err error) {
shs := s.opts.statsHandlers
if len(shs) != 0 || trInfo != nil || channelz.IsOn() {
if channelz.IsOn() {
s.incrCallsStarted()
}
var statsBegin *stats.Begin
for _, sh := range shs {
beginTime := time.Now()
statsBegin = &stats.Begin{
BeginTime: beginTime,
IsClientStream: false,
IsServerStream: false,
}
sh.HandleRPC(ctx, statsBegin)
}
if trInfo != nil {
trInfo.tr.LazyLog(&trInfo.firstLine, false)
}
// The deferred error handling for tracing, stats handler and channelz are
// combined into one function to reduce stack usage -- a defer takes ~56-64
// bytes on the stack, so overflowing the stack will require a stack
// re-allocation, which is expensive.
//
// To maintain behavior similar to separate deferred statements, statements
// should be executed in the reverse order. That is, tracing first, stats
// handler second, and channelz last. Note that panics *within* defers will
// lead to different behavior, but that's an acceptable compromise; that
// would be undefined behavior territory anyway.
defer func() {
if trInfo != nil {
if err != nil && err != io.EOF {
trInfo.tr.LazyLog(&fmtStringer{"%v", []any{err}}, true)
trInfo.tr.SetError()
}
trInfo.tr.Finish()
}
for _, sh := range shs {
end := &stats.End{
BeginTime: statsBegin.BeginTime,
EndTime: time.Now(),
}
if err != nil && err != io.EOF {
end.Error = toRPCErr(err)
}
sh.HandleRPC(ctx, end)
}
if channelz.IsOn() {
if err != nil && err != io.EOF {
s.incrCallsFailed()
} else {
s.incrCallsSucceeded()
}
}
}()
}
var binlogs []binarylog.MethodLogger
if ml := binarylog.GetMethodLogger(stream.Method()); ml != nil {
binlogs = append(binlogs, ml)
}
if s.opts.binaryLogger != nil {
if ml := s.opts.binaryLogger.GetMethodLogger(stream.Method()); ml != nil {
binlogs = append(binlogs, ml)
}
}
if len(binlogs) != 0 {
md, _ := metadata.FromIncomingContext(ctx)
logEntry := &binarylog.ClientHeader{
Header: md,
MethodName: stream.Method(),
PeerAddr: nil,
}
if deadline, ok := ctx.Deadline(); ok {
logEntry.Timeout = time.Until(deadline)
if logEntry.Timeout < 0 {
logEntry.Timeout = 0
}
}
if a := md[":authority"]; len(a) > 0 {
logEntry.Authority = a[0]
}
if peer, ok := peer.FromContext(ctx); ok {
logEntry.PeerAddr = peer.Addr
}
for _, binlog := range binlogs {
binlog.Log(ctx, logEntry)
}
}
// comp and cp are used for compression. decomp and dc are used for
// decompression. If comp and decomp are both set, they are the same;
// however they are kept separate to ensure that at most one of the
// compressor/decompressor variable pairs are set for use later.
var comp, decomp encoding.Compressor
var cp Compressor
var dc Decompressor
var sendCompressorName string
// If dc is set and matches the stream's compression, use it. Otherwise, try
// to find a matching registered compressor for decomp.
if rc := stream.RecvCompress(); s.opts.dc != nil && s.opts.dc.Type() == rc {
dc = s.opts.dc
} else if rc != "" && rc != encoding.Identity {
decomp = encoding.GetCompressor(rc)
if decomp == nil {
st := status.Newf(codes.Unimplemented, "grpc: Decompressor is not installed for grpc-encoding %q", rc)
t.WriteStatus(stream, st)
return st.Err()
}
}
// If cp is set, use it. Otherwise, attempt to compress the response using
// the incoming message compression method.
//
// NOTE: this needs to be ahead of all handling, https://github.com/grpc/grpc-go/issues/686.
if s.opts.cp != nil {
cp = s.opts.cp
sendCompressorName = cp.Type()
} else if rc := stream.RecvCompress(); rc != "" && rc != encoding.Identity {
// Legacy compressor not specified; attempt to respond with same encoding.
comp = encoding.GetCompressor(rc)
if comp != nil {
sendCompressorName = comp.Name()
}
}
if sendCompressorName != "" {
if err := stream.SetSendCompress(sendCompressorName); err != nil {
return status.Errorf(codes.Internal, "grpc: failed to set send compressor: %v", err)
}
}
var payInfo *payloadInfo
if len(shs) != 0 || len(binlogs) != 0 {
payInfo = &payloadInfo{}
}
d, cancel, err := recvAndDecompress(&parser{r: stream, recvBufferPool: s.opts.recvBufferPool}, stream, dc, s.opts.maxReceiveMessageSize, payInfo, decomp)
if err != nil {
if e := t.WriteStatus(stream, status.Convert(err)); e != nil {
channelz.Warningf(logger, s.channelz, "grpc: Server.processUnaryRPC failed to write status: %v", e)
}
return err
}
if channelz.IsOn() {
t.IncrMsgRecv()
}
df := func(v any) error {
defer cancel()
if err := s.getCodec(stream.ContentSubtype()).Unmarshal(d, v); err != nil {
return status.Errorf(codes.Internal, "grpc: error unmarshalling request: %v", err)
}
for _, sh := range shs {
sh.HandleRPC(ctx, &stats.InPayload{
RecvTime: time.Now(),
Payload: v,
Length: len(d),
WireLength: payInfo.compressedLength + headerLen,
CompressedLength: payInfo.compressedLength,
Data: d,
})
}
if len(binlogs) != 0 {
cm := &binarylog.ClientMessage{
Message: d,
}
for _, binlog := range binlogs {
binlog.Log(ctx, cm)
}
}
if trInfo != nil {
trInfo.tr.LazyLog(&payload{sent: false, msg: v}, true)
}
return nil
}
ctx = NewContextWithServerTransportStream(ctx, stream)
reply, appErr := md.Handler(info.serviceImpl, ctx, df, s.opts.unaryInt)
if appErr != nil {
appStatus, ok := status.FromError(appErr)
if !ok {
// Convert non-status application error to a status error with code
// Unknown, but handle context errors specifically.
appStatus = status.FromContextError(appErr)
appErr = appStatus.Err()
}
if trInfo != nil {
trInfo.tr.LazyLog(stringer(appStatus.Message()), true)
trInfo.tr.SetError()
}
if e := t.WriteStatus(stream, appStatus); e != nil {
channelz.Warningf(logger, s.channelz, "grpc: Server.processUnaryRPC failed to write status: %v", e)
}
if len(binlogs) != 0 {
if h, _ := stream.Header(); h.Len() > 0 {
// Only log serverHeader if there was header. Otherwise it can
// be trailer only.
sh := &binarylog.ServerHeader{
Header: h,
}
for _, binlog := range binlogs {
binlog.Log(ctx, sh)
}
}
st := &binarylog.ServerTrailer{
Trailer: stream.Trailer(),
Err: appErr,
}
for _, binlog := range binlogs {
binlog.Log(ctx, st)
}
}
return appErr
}
if trInfo != nil {
trInfo.tr.LazyLog(stringer("OK"), false)
}
opts := &transport.Options{Last: true}
// Server handler could have set new compressor by calling SetSendCompressor.
// In case it is set, we need to use it for compressing outbound message.
if stream.SendCompress() != sendCompressorName {
comp = encoding.GetCompressor(stream.SendCompress())
}
if err := s.sendResponse(ctx, t, stream, reply, cp, opts, comp); err != nil {
if err == io.EOF {
// The entire stream is done (for unary RPC only).
return err
}
if sts, ok := status.FromError(err); ok {
if e := t.WriteStatus(stream, sts); e != nil {
channelz.Warningf(logger, s.channelz, "grpc: Server.processUnaryRPC failed to write status: %v", e)
}
} else {
switch st := err.(type) {
case transport.ConnectionError:
// Nothing to do here.
default:
panic(fmt.Sprintf("grpc: Unexpected error (%T) from sendResponse: %v", st, st))
}
}
if len(binlogs) != 0 {
h, _ := stream.Header()
sh := &binarylog.ServerHeader{
Header: h,
}
st := &binarylog.ServerTrailer{
Trailer: stream.Trailer(),
Err: appErr,
}
for _, binlog := range binlogs {
binlog.Log(ctx, sh)
binlog.Log(ctx, st)
}
}
return err
}
if len(binlogs) != 0 {
h, _ := stream.Header()
sh := &binarylog.ServerHeader{
Header: h,
}
sm := &binarylog.ServerMessage{
Message: reply,
}
for _, binlog := range binlogs {
binlog.Log(ctx, sh)
binlog.Log(ctx, sm)
}
}
if channelz.IsOn() {
t.IncrMsgSent()
}
if trInfo != nil {
trInfo.tr.LazyLog(&payload{sent: true, msg: reply}, true)
}
// TODO: Should we be logging if writing status failed here, like above?
// Should the logging be in WriteStatus? Should we ignore the WriteStatus
// error or allow the stats handler to see it?
if len(binlogs) != 0 {
st := &binarylog.ServerTrailer{
Trailer: stream.Trailer(),
Err: appErr,
}
for _, binlog := range binlogs {
binlog.Log(ctx, st)
}
}
return t.WriteStatus(stream, statusOK)
}
// chainStreamServerInterceptors chains all stream server interceptors into one.
func chainStreamServerInterceptors(s *Server) {
// Prepend opts.streamInt to the chaining interceptors if it exists, since streamInt will
// be executed before any other chained interceptors.
interceptors := s.opts.chainStreamInts
if s.opts.streamInt != nil {
interceptors = append([]StreamServerInterceptor{s.opts.streamInt}, s.opts.chainStreamInts...)
}
var chainedInt StreamServerInterceptor
if len(interceptors) == 0 {
chainedInt = nil
} else if len(interceptors) == 1 {
chainedInt = interceptors[0]
} else {
chainedInt = chainStreamInterceptors(interceptors)
}
s.opts.streamInt = chainedInt
}
func chainStreamInterceptors(interceptors []StreamServerInterceptor) StreamServerInterceptor {
return func(srv any, ss ServerStream, info *StreamServerInfo, handler StreamHandler) error {
return interceptors[0](srv, ss, info, getChainStreamHandler(interceptors, 0, info, handler))
}
}
func getChainStreamHandler(interceptors []StreamServerInterceptor, curr int, info *StreamServerInfo, finalHandler StreamHandler) StreamHandler {
if curr == len(interceptors)-1 {
return finalHandler
}
return func(srv any, stream ServerStream) error {
return interceptors[curr+1](srv, stream, info, getChainStreamHandler(interceptors, curr+1, info, finalHandler))
}
}
func (s *Server) processStreamingRPC(ctx context.Context, t transport.ServerTransport, stream *transport.Stream, info *serviceInfo, sd *StreamDesc, trInfo *traceInfo) (err error) {
if channelz.IsOn() {
s.incrCallsStarted()
}
shs := s.opts.statsHandlers
var statsBegin *stats.Begin
if len(shs) != 0 {
beginTime := time.Now()
statsBegin = &stats.Begin{
BeginTime: beginTime,
IsClientStream: sd.ClientStreams,
IsServerStream: sd.ServerStreams,
}
for _, sh := range shs {
sh.HandleRPC(ctx, statsBegin)
}
}
ctx = NewContextWithServerTransportStream(ctx, stream)
ss := &serverStream{
ctx: ctx,
t: t,
s: stream,
p: &parser{r: stream, recvBufferPool: s.opts.recvBufferPool},
codec: s.getCodec(stream.ContentSubtype()),
maxReceiveMessageSize: s.opts.maxReceiveMessageSize,
maxSendMessageSize: s.opts.maxSendMessageSize,
trInfo: trInfo,
statsHandler: shs,
}
if len(shs) != 0 || trInfo != nil || channelz.IsOn() {
// See comment in processUnaryRPC on defers.
defer func() {
if trInfo != nil {
ss.mu.Lock()
if err != nil && err != io.EOF {
ss.trInfo.tr.LazyLog(&fmtStringer{"%v", []any{err}}, true)
ss.trInfo.tr.SetError()
}
ss.trInfo.tr.Finish()
ss.trInfo.tr = nil
ss.mu.Unlock()
}
if len(shs) != 0 {
end := &stats.End{
BeginTime: statsBegin.BeginTime,
EndTime: time.Now(),
}
if err != nil && err != io.EOF {
end.Error = toRPCErr(err)
}
for _, sh := range shs {
sh.HandleRPC(ctx, end)
}
}
if channelz.IsOn() {
if err != nil && err != io.EOF {
s.incrCallsFailed()
} else {
s.incrCallsSucceeded()
}
}
}()
}
if ml := binarylog.GetMethodLogger(stream.Method()); ml != nil {
ss.binlogs = append(ss.binlogs, ml)
}
if s.opts.binaryLogger != nil {
if ml := s.opts.binaryLogger.GetMethodLogger(stream.Method()); ml != nil {
ss.binlogs = append(ss.binlogs, ml)
}
}
if len(ss.binlogs) != 0 {
md, _ := metadata.FromIncomingContext(ctx)
logEntry := &binarylog.ClientHeader{
Header: md,
MethodName: stream.Method(),
PeerAddr: nil,
}
if deadline, ok := ctx.Deadline(); ok {
logEntry.Timeout = time.Until(deadline)
if logEntry.Timeout < 0 {
logEntry.Timeout = 0
}
}
if a := md[":authority"]; len(a) > 0 {
logEntry.Authority = a[0]
}
if peer, ok := peer.FromContext(ss.Context()); ok {
logEntry.PeerAddr = peer.Addr
}
for _, binlog := range ss.binlogs {
binlog.Log(ctx, logEntry)
}
}
// If dc is set and matches the stream's compression, use it. Otherwise, try
// to find a matching registered compressor for decomp.
if rc := stream.RecvCompress(); s.opts.dc != nil && s.opts.dc.Type() == rc {
ss.dc = s.opts.dc
} else if rc != "" && rc != encoding.Identity {
ss.decomp = encoding.GetCompressor(rc)
if ss.decomp == nil {
st := status.Newf(codes.Unimplemented, "grpc: Decompressor is not installed for grpc-encoding %q", rc)
t.WriteStatus(ss.s, st)
return st.Err()
}
}
// If cp is set, use it. Otherwise, attempt to compress the response using
// the incoming message compression method.
//
// NOTE: this needs to be ahead of all handling, https://github.com/grpc/grpc-go/issues/686.
if s.opts.cp != nil {
ss.cp = s.opts.cp
ss.sendCompressorName = s.opts.cp.Type()
} else if rc := stream.RecvCompress(); rc != "" && rc != encoding.Identity {
// Legacy compressor not specified; attempt to respond with same encoding.
ss.comp = encoding.GetCompressor(rc)
if ss.comp != nil {
ss.sendCompressorName = rc
}
}
if ss.sendCompressorName != "" {
if err := stream.SetSendCompress(ss.sendCompressorName); err != nil {
return status.Errorf(codes.Internal, "grpc: failed to set send compressor: %v", err)
}
}
ss.ctx = newContextWithRPCInfo(ss.ctx, false, ss.codec, ss.cp, ss.comp)
if trInfo != nil {
trInfo.tr.LazyLog(&trInfo.firstLine, false)
}
var appErr error
var server any
if info != nil {
server = info.serviceImpl
}
if s.opts.streamInt == nil {
appErr = sd.Handler(server, ss)
} else {
info := &StreamServerInfo{
FullMethod: stream.Method(),
IsClientStream: sd.ClientStreams,
IsServerStream: sd.ServerStreams,
}
appErr = s.opts.streamInt(server, ss, info, sd.Handler)
}
if appErr != nil {
appStatus, ok := status.FromError(appErr)
if !ok {
// Convert non-status application error to a status error with code
// Unknown, but handle context errors specifically.
appStatus = status.FromContextError(appErr)
appErr = appStatus.Err()
}
if trInfo != nil {
ss.mu.Lock()
ss.trInfo.tr.LazyLog(stringer(appStatus.Message()), true)
ss.trInfo.tr.SetError()
ss.mu.Unlock()
}
if len(ss.binlogs) != 0 {
st := &binarylog.ServerTrailer{
Trailer: ss.s.Trailer(),
Err: appErr,
}
for _, binlog := range ss.binlogs {
binlog.Log(ctx, st)
}
}
t.WriteStatus(ss.s, appStatus)
// TODO: Should we log an error from WriteStatus here and below?
return appErr
}
if trInfo != nil {
ss.mu.Lock()
ss.trInfo.tr.LazyLog(stringer("OK"), false)
ss.mu.Unlock()
}
if len(ss.binlogs) != 0 {
st := &binarylog.ServerTrailer{
Trailer: ss.s.Trailer(),
Err: appErr,
}
for _, binlog := range ss.binlogs {
binlog.Log(ctx, st)
}
}
return t.WriteStatus(ss.s, statusOK)
}
func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Stream) {
ctx := stream.Context()
ctx = contextWithServer(ctx, s)
var ti *traceInfo
if EnableTracing {
tr := newTrace("grpc.Recv."+methodFamily(stream.Method()), stream.Method())
ctx = newTraceContext(ctx, tr)
ti = &traceInfo{
tr: tr,
firstLine: firstLine{
client: false,
remoteAddr: t.Peer().Addr,
},
}
if dl, ok := ctx.Deadline(); ok {
ti.firstLine.deadline = time.Until(dl)
}
}
sm := stream.Method()
if sm != "" && sm[0] == '/' {
sm = sm[1:]
}
pos := strings.LastIndex(sm, "/")
if pos == -1 {
if ti != nil {
ti.tr.LazyLog(&fmtStringer{"Malformed method name %q", []any{sm}}, true)
ti.tr.SetError()
}
errDesc := fmt.Sprintf("malformed method name: %q", stream.Method())
if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
if ti != nil {
ti.tr.LazyLog(&fmtStringer{"%v", []any{err}}, true)
ti.tr.SetError()
}
channelz.Warningf(logger, s.channelz, "grpc: Server.handleStream failed to write status: %v", err)
}
if ti != nil {
ti.tr.Finish()
}
return
}
service := sm[:pos]
method := sm[pos+1:]
md, _ := metadata.FromIncomingContext(ctx)
for _, sh := range s.opts.statsHandlers {
ctx = sh.TagRPC(ctx, &stats.RPCTagInfo{FullMethodName: stream.Method()})
sh.HandleRPC(ctx, &stats.InHeader{
FullMethod: stream.Method(),
RemoteAddr: t.Peer().Addr,
LocalAddr: t.Peer().LocalAddr,
Compression: stream.RecvCompress(),
WireLength: stream.HeaderWireLength(),
Header: md,
})
}
// To have calls in stream callouts work. Will delete once all stats handler
// calls come from the gRPC layer.
stream.SetContext(ctx)
srv, knownService := s.services[service]
if knownService {
if md, ok := srv.methods[method]; ok {
s.processUnaryRPC(ctx, t, stream, srv, md, ti)
return
}
if sd, ok := srv.streams[method]; ok {
s.processStreamingRPC(ctx, t, stream, srv, sd, ti)
return
}
}
// Unknown service, or known server unknown method.
if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
s.processStreamingRPC(ctx, t, stream, nil, unknownDesc, ti)
return
}
var errDesc string
if !knownService {
errDesc = fmt.Sprintf("unknown service %v", service)
} else {
errDesc = fmt.Sprintf("unknown method %v for service %v", method, service)
}
if ti != nil {
ti.tr.LazyPrintf("%s", errDesc)
ti.tr.SetError()
}
if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
if ti != nil {
ti.tr.LazyLog(&fmtStringer{"%v", []any{err}}, true)
ti.tr.SetError()
}
channelz.Warningf(logger, s.channelz, "grpc: Server.handleStream failed to write status: %v", err)
}
if ti != nil {
ti.tr.Finish()
}
}
// The key to save ServerTransportStream in the context.
type streamKey struct{}
// NewContextWithServerTransportStream creates a new context from ctx and
// attaches stream to it.
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func NewContextWithServerTransportStream(ctx context.Context, stream ServerTransportStream) context.Context {
return context.WithValue(ctx, streamKey{}, stream)
}
// ServerTransportStream is a minimal interface that a transport stream must
// implement. This can be used to mock an actual transport stream for tests of
// handler code that use, for example, grpc.SetHeader (which requires some
// stream to be in context).
//
// See also NewContextWithServerTransportStream.
//
// # Experimental
//
// Notice: This type is EXPERIMENTAL and may be changed or removed in a
// later release.
type ServerTransportStream interface {
Method() string
SetHeader(md metadata.MD) error
SendHeader(md metadata.MD) error
SetTrailer(md metadata.MD) error
}
// ServerTransportStreamFromContext returns the ServerTransportStream saved in
// ctx. Returns nil if the given context has no stream associated with it
// (which implies it is not an RPC invocation context).
//
// # Experimental
//
// Notice: This API is EXPERIMENTAL and may be changed or removed in a
// later release.
func ServerTransportStreamFromContext(ctx context.Context) ServerTransportStream {
s, _ := ctx.Value(streamKey{}).(ServerTransportStream)
return s
}
// Stop stops the gRPC server. It immediately closes all open
// connections and listeners.
// It cancels all active RPCs on the server side and the corresponding
// pending RPCs on the client side will get notified by connection
// errors.
func (s *Server) Stop() {
s.stop(false)
}
// GracefulStop stops the gRPC server gracefully. It stops the server from
// accepting new connections and RPCs and blocks until all the pending RPCs are
// finished.
func (s *Server) GracefulStop() {
s.stop(true)
}
func (s *Server) stop(graceful bool) {
s.quit.Fire()
defer s.done.Fire()
s.channelzRemoveOnce.Do(func() { channelz.RemoveEntry(s.channelz.ID) })
s.mu.Lock()
s.closeListenersLocked()
// Wait for serving threads to be ready to exit. Only then can we be sure no
// new conns will be created.
s.mu.Unlock()
s.serveWG.Wait()
s.mu.Lock()
defer s.mu.Unlock()
if graceful {
s.drainAllServerTransportsLocked()
} else {
s.closeServerTransportsLocked()
}
for len(s.conns) != 0 {
s.cv.Wait()
}
s.conns = nil
if s.opts.numServerWorkers > 0 {
// Closing the channel (only once, via grpcsync.OnceFunc) after all the
// connections have been closed above ensures that there are no
// goroutines executing the callback passed to st.HandleStreams (where
// the channel is written to).
s.serverWorkerChannelClose()
}
if graceful || s.opts.waitForHandlers {
s.handlersWG.Wait()
}
if s.events != nil {
s.events.Finish()
s.events = nil
}
}
// s.mu must be held by the caller.
func (s *Server) closeServerTransportsLocked() {
for _, conns := range s.conns {
for st := range conns {
st.Close(errors.New("Server.Stop called"))
}
}
}
// s.mu must be held by the caller.
func (s *Server) drainAllServerTransportsLocked() {
if !s.drain {
for _, conns := range s.conns {
for st := range conns {
st.Drain("graceful_stop")
}
}
s.drain = true
}
}
// s.mu must be held by the caller.
func (s *Server) closeListenersLocked() {
for lis := range s.lis {
lis.Close()
}
s.lis = nil
}
// contentSubtype must be lowercase
// cannot return nil
func (s *Server) getCodec(contentSubtype string) baseCodec {
if s.opts.codec != nil {
return s.opts.codec
}
if contentSubtype == "" {
return encoding.GetCodec(proto.Name)
}
codec := encoding.GetCodec(contentSubtype)
if codec == nil {
logger.Warningf("Unsupported codec %q. Defaulting to %q for now. This will start to fail in future releases.", contentSubtype, proto.Name)
return encoding.GetCodec(proto.Name)
}
return codec
}
type serverKey struct{}
// serverFromContext gets the Server from the context.
func serverFromContext(ctx context.Context) *Server {
s, _ := ctx.Value(serverKey{}).(*Server)
return s
}
// contextWithServer sets the Server in the context.
func contextWithServer(ctx context.Context, server *Server) context.Context {
return context.WithValue(ctx, serverKey{}, server)
}
// isRegisteredMethod returns whether the passed in method is registered as a
// method on the server. /service/method and service/method will match if the
// service and method are registered on the server.
func (s *Server) isRegisteredMethod(serviceMethod string) bool {
if serviceMethod != "" && serviceMethod[0] == '/' {
serviceMethod = serviceMethod[1:]
}
pos := strings.LastIndex(serviceMethod, "/")
if pos == -1 { // Invalid method name syntax.
return false
}
service := serviceMethod[:pos]
method := serviceMethod[pos+1:]
srv, knownService := s.services[service]
if knownService {
if _, ok := srv.methods[method]; ok {
return true
}
if _, ok := srv.streams[method]; ok {
return true
}
}
return false
}
// SetHeader sets the header metadata to be sent from the server to the client.
// The context provided must be the context passed to the server's handler.
//
// Streaming RPCs should prefer the SetHeader method of the ServerStream.
//
// When called multiple times, all the provided metadata will be merged. All
// the metadata will be sent out when one of the following happens:
//
// - grpc.SendHeader is called, or for streaming handlers, stream.SendHeader.
// - The first response message is sent. For unary handlers, this occurs when
// the handler returns; for streaming handlers, this can happen when stream's
// SendMsg method is called.
// - An RPC status is sent out (error or success). This occurs when the handler
// returns.
//
// SetHeader will fail if called after any of the events above.
//
// The error returned is compatible with the status package. However, the
// status code will often not match the RPC status as seen by the client
// application, and therefore, should not be relied upon for this purpose.
func SetHeader(ctx context.Context, md metadata.MD) error {
if md.Len() == 0 {
return nil
}
stream := ServerTransportStreamFromContext(ctx)
if stream == nil {
return status.Errorf(codes.Internal, "grpc: failed to fetch the stream from the context %v", ctx)
}
return stream.SetHeader(md)
}
// SendHeader sends header metadata. It may be called at most once, and may not
// be called after any event that causes headers to be sent (see SetHeader for
// a complete list). The provided md and headers set by SetHeader() will be
// sent.
//
// The error returned is compatible with the status package. However, the
// status code will often not match the RPC status as seen by the client
// application, and therefore, should not be relied upon for this purpose.
func SendHeader(ctx context.Context, md metadata.MD) error {
stream := ServerTransportStreamFromContext(ctx)
if stream == nil {
return status.Errorf(codes.Internal, "grpc: failed to fetch the stream from the context %v", ctx)
}
if err := stream.SendHeader(md); err != nil {
return toRPCErr(err)
}
return nil
}
// SetSendCompressor sets a compressor for outbound messages from the server.
// It must not be called after any event that causes headers to be sent
// (see ServerStream.SetHeader for the complete list). Provided compressor is
// used when below conditions are met:
//
// - compressor is registered via encoding.RegisterCompressor
// - compressor name must exist in the client advertised compressor names
// sent in grpc-accept-encoding header. Use ClientSupportedCompressors to
// get client supported compressor names.
//
// The context provided must be the context passed to the server's handler.
// It must be noted that compressor name encoding.Identity disables the
// outbound compression.
// By default, server messages will be sent using the same compressor with
// which request messages were sent.
//
// It is not safe to call SetSendCompressor concurrently with SendHeader and
// SendMsg.
//
// # Experimental
//
// Notice: This function is EXPERIMENTAL and may be changed or removed in a
// later release.
func SetSendCompressor(ctx context.Context, name string) error {
stream, ok := ServerTransportStreamFromContext(ctx).(*transport.Stream)
if !ok || stream == nil {
return fmt.Errorf("failed to fetch the stream from the given context")
}
if err := validateSendCompressor(name, stream.ClientAdvertisedCompressors()); err != nil {
return fmt.Errorf("unable to set send compressor: %w", err)
}
return stream.SetSendCompress(name)
}
// ClientSupportedCompressors returns compressor names advertised by the client
// via grpc-accept-encoding header.
//
// The context provided must be the context passed to the server's handler.
//
// # Experimental
//
// Notice: This function is EXPERIMENTAL and may be changed or removed in a
// later release.
func ClientSupportedCompressors(ctx context.Context) ([]string, error) {
stream, ok := ServerTransportStreamFromContext(ctx).(*transport.Stream)
if !ok || stream == nil {
return nil, fmt.Errorf("failed to fetch the stream from the given context %v", ctx)
}
return stream.ClientAdvertisedCompressors(), nil
}
// SetTrailer sets the trailer metadata that will be sent when an RPC returns.
// When called more than once, all the provided metadata will be merged.
//
// The error returned is compatible with the status package. However, the
// status code will often not match the RPC status as seen by the client
// application, and therefore, should not be relied upon for this purpose.
func SetTrailer(ctx context.Context, md metadata.MD) error {
if md.Len() == 0 {
return nil
}
stream := ServerTransportStreamFromContext(ctx)
if stream == nil {
return status.Errorf(codes.Internal, "grpc: failed to fetch the stream from the context %v", ctx)
}
return stream.SetTrailer(md)
}
// Method returns the method string for the server context. The returned
// string is in the format of "/service/method".
func Method(ctx context.Context) (string, bool) {
s := ServerTransportStreamFromContext(ctx)
if s == nil {
return "", false
}
return s.Method(), true
}
// validateSendCompressor returns an error when given compressor name cannot be
// handled by the server or the client based on the advertised compressors.
func validateSendCompressor(name string, clientCompressors []string) error {
if name == encoding.Identity {
return nil
}
if !grpcutil.IsCompressorNameRegistered(name) {
return fmt.Errorf("compressor not registered %q", name)
}
for _, c := range clientCompressors {
if c == name {
return nil // found match
}
}
return fmt.Errorf("client does not support compressor %q", name)
}
// atomicSemaphore implements a blocking, counting semaphore. acquire should be
// called synchronously; release may be called asynchronously.
type atomicSemaphore struct {
n atomic.Int64
wait chan struct{}
}
func (q *atomicSemaphore) acquire() {
if q.n.Add(-1) < 0 {
// We ran out of quota. Block until a release happens.
<-q.wait
}
}
func (q *atomicSemaphore) release() {
// N.B. the "<= 0" check below should allow for this to work with multiple
// concurrent calls to acquire, but also note that with synchronous calls to
// acquire, as our system does, n will never be less than -1. There are
// fairness issues (queuing) to consider if this was to be generalized.
if q.n.Add(1) <= 0 {
// An acquire was waiting on us. Unblock it.
q.wait <- struct{}{}
}
}
func newHandlerQuota(n uint32) *atomicSemaphore {
a := &atomicSemaphore{wait: make(chan struct{}, 1)}
a.n.Store(int64(n))
return a
}