grpc/service/service.go
Adphi 6e86120943
add server interface interceptors
Signed-off-by: Adphi <philippe.adrien.nousse@gmail.com>
2022-07-15 15:48:09 +02:00

388 lines
8.7 KiB
Go

package service
import (
"context"
"crypto/tls"
"fmt"
"net"
"net/http"
"os"
"os/signal"
"reflect"
"strings"
"sync"
"syscall"
"time"
"github.com/fullstorydev/grpchan/inprocgrpc"
"github.com/google/uuid"
grpcmiddleware "github.com/grpc-ecosystem/go-grpc-middleware"
"github.com/jinzhu/gorm"
"github.com/justinas/alice"
"github.com/rs/cors"
"github.com/soheilhy/cmux"
"go.uber.org/multierr"
"google.golang.org/grpc"
"google.golang.org/grpc/health"
"google.golang.org/grpc/health/grpc_health_v1"
greflect "google.golang.org/grpc/reflection"
"go.linka.cloud/grpc/logger"
"go.linka.cloud/grpc/registry"
"go.linka.cloud/grpc/registry/noop"
)
type Service interface {
greflect.GRPCServer
Options() Options
DB() *gorm.DB
Start() error
Stop() error
Close() error
}
func New(opts ...Option) (Service, error) {
return newService(opts...)
}
type service struct {
opts *options
cancel context.CancelFunc
server *grpc.Server
mu sync.Mutex
running bool
// inproc Channel is used to serve grpc gateway
inproc *inprocgrpc.Channel
services map[string]*serviceInfo
id string
regSvc *registry.Service
closed chan struct{}
}
func newService(opts ...Option) (*service, error) {
s := &service{
opts: NewOptions(),
id: uuid.New().String(),
inproc: &inprocgrpc.Channel{},
services: make(map[string]*serviceInfo),
}
s.mu.Lock()
defer s.mu.Unlock()
for _, f := range opts {
f(s.opts)
}
md := md(s.opts)
if md != nil {
s.opts.unaryServerInterceptors = append([]grpc.UnaryServerInterceptor{md.UnaryServerInterceptor()}, s.opts.unaryServerInterceptors...)
s.opts.unaryClientInterceptors = append([]grpc.UnaryClientInterceptor{md.UnaryClientInterceptor()}, s.opts.unaryClientInterceptors...)
s.opts.streamServerInterceptors = append([]grpc.StreamServerInterceptor{md.StreamServerInterceptor()}, s.opts.streamServerInterceptors...)
s.opts.streamClientInterceptors = append([]grpc.StreamClientInterceptor{md.StreamClientInterceptor()}, s.opts.streamClientInterceptors...)
}
if s.opts.mux == nil {
s.opts.mux = http.NewServeMux()
}
if s.opts.error != nil {
return nil, s.opts.error
}
s.opts.ctx, s.cancel = context.WithCancel(s.opts.ctx)
go func() {
for {
select {
case <-s.opts.ctx.Done():
s.Stop()
}
}
}()
if s.opts.registry == nil {
s.opts.registry = noop.New()
}
if err := s.opts.parseTLSConfig(); err != nil {
return nil, err
}
ui := grpcmiddleware.ChainUnaryServer(s.opts.unaryServerInterceptors...)
s.inproc = s.inproc.WithServerUnaryInterceptor(ui)
si := grpcmiddleware.ChainStreamServer(s.opts.streamServerInterceptors...)
s.inproc = s.inproc.WithServerStreamInterceptor(si)
gopts := []grpc.ServerOption{
grpc.StreamInterceptor(si),
grpc.UnaryInterceptor(ui),
}
s.server = grpc.NewServer(append(gopts, s.opts.serverOpts...)...)
if s.opts.reflection {
greflect.Register(s.server)
}
if s.opts.health {
s.registerService(&grpc_health_v1.Health_ServiceDesc, health.NewServer())
}
if err := s.gateway(s.opts.gatewayOpts...); err != nil {
return nil, err
}
if err := s.reactApp(); err != nil {
return nil, err
}
// we do not configure grpc web here as the grpc handlers are not yet registered
return s, nil
}
func (s *service) Options() Options {
return s.opts
}
func (s *service) DB() *gorm.DB {
return s.opts.db
}
func (s *service) run() error {
s.mu.Lock()
s.closed = make(chan struct{})
// configure grpc web now that we are ready to go
if err := s.grpcWeb(s.opts.grpcWebOpts...); err != nil {
return err
}
lis, err := net.Listen("tcp", s.opts.address)
if err != nil {
return err
}
if s.opts.tlsConfig != nil {
lis = tls.NewListener(lis, s.opts.tlsConfig)
}
s.opts.address = lis.Addr().String()
mux := cmux.New(lis)
mux.SetReadTimeout(5 * time.Second)
gLis := mux.MatchWithWriters(cmux.HTTP2MatchHeaderFieldSendSettings("content-type", "application/grpc"))
hList := mux.Match(cmux.Any())
for i := range s.opts.beforeStart {
if err := s.opts.beforeStart[i](); err != nil {
s.mu.Unlock()
return err
}
}
if err := s.register(); err != nil {
return err
}
s.running = true
errs := make(chan error, 3)
if reflect.DeepEqual(s.opts.cors, cors.Options{}) {
s.opts.cors = cors.Options{
AllowedHeaders: []string{"*"},
AllowedMethods: []string{
http.MethodGet,
http.MethodPost,
http.MethodPut,
http.MethodPatch,
http.MethodDelete,
http.MethodOptions,
http.MethodHead,
},
AllowedOrigins: []string{"*"},
AllowCredentials: true,
}
}
hServer := &http.Server{
Handler: alice.New(s.opts.middlewares...).Then(cors.New(s.opts.cors).Handler(s.opts.mux)),
}
if s.opts.Gateway() || s.opts.grpcWeb || s.opts.hasReactUI {
go func() {
errs <- hServer.Serve(hList)
hServer.Shutdown(s.opts.ctx)
}()
}
go func() {
errs <- s.server.Serve(gLis)
}()
go func() {
if err := mux.Serve(); err != nil {
// TODO(adphi): find more elegant solution
if ignoreMuxError(err) {
errs <- nil
return
}
errs <- err
return
}
errs <- nil
}()
for i := range s.opts.afterStart {
if err := s.opts.afterStart[i](); err != nil {
s.mu.Unlock()
s.Stop()
return err
}
}
s.mu.Unlock()
sigs := s.notify()
select {
case sig := <-sigs:
fmt.Println()
logger.C(s.opts.ctx).Warnf("received %v", sig)
return s.Close()
case err := <-errs:
if err != nil && !ignoreMuxError(err) {
logger.C(s.opts.ctx).Error(err)
return err
}
return nil
}
}
func (s *service) Start() error {
return s.run()
}
func (s *service) Stop() error {
log := logger.C(s.opts.ctx)
s.mu.Lock()
defer s.mu.Unlock()
if !s.running {
return nil
}
for i := range s.opts.beforeStop {
if err := s.opts.beforeStop[i](); err != nil {
return err
}
}
if err := s.opts.registry.Deregister(s.regSvc); err != nil {
log.Errorf("failed to deregister service: %v", err)
}
defer close(s.closed)
sigs := s.notify()
done := make(chan struct{})
go func() {
defer close(done)
// TODO(adphi): find a better solution
defer func() {
// catch: Drain() is not implemented
recover()
}()
log.Warn("shutting down gracefully")
s.server.GracefulStop()
}()
select {
case sig := <-sigs:
fmt.Println()
log.Warnf("received %v", sig)
log.Warn("forcing shutdown")
s.server.Stop()
case <-done:
}
s.running = false
s.cancel()
for i := range s.opts.afterStop {
if err := s.opts.afterStop[i](); err != nil {
return err
}
}
log.Info("server stopped")
return nil
}
func (s *service) RegisterService(desc *grpc.ServiceDesc, impl interface{}) {
s.mu.Lock()
defer s.mu.Unlock()
s.registerService(desc, impl)
}
// 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 interface{}
methods map[string]*grpc.MethodDesc
streams map[string]*grpc.StreamDesc
mdata interface{}
}
func (s *service) registerService(sd *grpc.ServiceDesc, ss interface{}) {
s.server.RegisterService(sd, ss)
s.inproc.RegisterService(sd, ss)
if _, ok := s.services[sd.ServiceName]; ok {
logger.C(s.opts.ctx).Fatalf("grpc: Service.RegisterService found duplicate service registration for %q", sd.ServiceName)
}
info := &serviceInfo{
serviceImpl: ss,
methods: make(map[string]*grpc.MethodDesc),
streams: make(map[string]*grpc.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
}
func (s *service) GetServiceInfo() map[string]grpc.ServiceInfo {
ret := make(map[string]grpc.ServiceInfo)
for n, srv := range s.services {
methods := make([]grpc.MethodInfo, 0, len(srv.methods)+len(srv.streams))
for m := range srv.methods {
methods = append(methods, grpc.MethodInfo{
Name: m,
IsClientStream: false,
IsServerStream: false,
})
}
for m, d := range srv.streams {
methods = append(methods, grpc.MethodInfo{
Name: m,
IsClientStream: d.ClientStreams,
IsServerStream: d.ServerStreams,
})
}
ret[n] = grpc.ServiceInfo{
Methods: methods,
Metadata: srv.mdata,
}
}
return ret
}
func (s *service) Close() error {
err := multierr.Combine(s.Stop())
if s.opts.db != nil {
err = multierr.Append(s.opts.db.Close(), err)
}
<-s.closed
return err
}
func (s *service) notify() <-chan os.Signal {
sigs := make(chan os.Signal, 2)
signal.Notify(sigs, syscall.SIGINT, syscall.SIGQUIT)
return sigs
}
func ignoreMuxError(err error) bool {
if err == nil {
return true
}
return strings.Contains(err.Error(), "use of closed network connection") ||
strings.Contains(err.Error(), "mux: server closed")
}