micro/server/grpc/grpc.go
2019-07-08 08:01:42 +01:00

794 lines
17 KiB
Go

// Package grpc provides a grpc server
package grpc
import (
"context"
"crypto/tls"
"fmt"
"net"
"reflect"
"sort"
"strconv"
"strings"
"sync"
"time"
"github.com/micro/go-micro/broker"
"github.com/micro/go-micro/codec"
"github.com/micro/go-micro/errors"
meta "github.com/micro/go-micro/metadata"
"github.com/micro/go-micro/registry"
"github.com/micro/go-micro/server"
"github.com/micro/go-micro/util/addr"
mgrpc "github.com/micro/go-micro/util/grpc"
"github.com/micro/go-micro/util/log"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/credentials"
"google.golang.org/grpc/encoding"
"google.golang.org/grpc/metadata"
"google.golang.org/grpc/peer"
"google.golang.org/grpc/status"
)
var (
// DefaultMaxMsgSize define maximum message size that server can send
// or receive. Default value is 4MB.
DefaultMaxMsgSize = 1024 * 1024 * 4
)
const (
defaultContentType = "application/grpc"
)
type grpcServer struct {
rpc *rServer
srv *grpc.Server
exit chan chan error
wg *sync.WaitGroup
sync.RWMutex
opts server.Options
handlers map[string]server.Handler
subscribers map[*subscriber][]broker.Subscriber
// used for first registration
registered bool
}
func init() {
encoding.RegisterCodec(wrapCodec{jsonCodec{}})
encoding.RegisterCodec(wrapCodec{protoCodec{}})
encoding.RegisterCodec(wrapCodec{bytesCodec{}})
}
func newGRPCServer(opts ...server.Option) server.Server {
options := newOptions(opts...)
// create a grpc server
srv := &grpcServer{
opts: options,
rpc: &rServer{
serviceMap: make(map[string]*service),
},
handlers: make(map[string]server.Handler),
subscribers: make(map[*subscriber][]broker.Subscriber),
exit: make(chan chan error),
wg: wait(options.Context),
}
// configure the grpc server
srv.configure()
return srv
}
type grpcRouter struct {
h func(context.Context, server.Request, interface{}) error
}
func (r grpcRouter) ServeRequest(ctx context.Context, req server.Request, rsp server.Response) error {
return r.h(ctx, req, rsp)
}
func (g *grpcServer) configure(opts ...server.Option) {
// Don't reprocess where there's no config
if len(opts) == 0 && g.srv != nil {
return
}
for _, o := range opts {
o(&g.opts)
}
maxMsgSize := g.getMaxMsgSize()
gopts := []grpc.ServerOption{
grpc.MaxRecvMsgSize(maxMsgSize),
grpc.MaxSendMsgSize(maxMsgSize),
grpc.UnknownServiceHandler(g.handler),
}
if creds := g.getCredentials(); creds != nil {
gopts = append(gopts, grpc.Creds(creds))
}
if opts := g.getGrpcOptions(); opts != nil {
gopts = append(gopts, opts...)
}
g.srv = grpc.NewServer(gopts...)
}
func (g *grpcServer) getMaxMsgSize() int {
if g.opts.Context == nil {
return DefaultMaxMsgSize
}
s, ok := g.opts.Context.Value(maxMsgSizeKey{}).(int)
if !ok {
return DefaultMaxMsgSize
}
return s
}
func (g *grpcServer) getCredentials() credentials.TransportCredentials {
if g.opts.Context != nil {
if v := g.opts.Context.Value(tlsAuth{}); v != nil {
tls := v.(*tls.Config)
return credentials.NewTLS(tls)
}
}
return nil
}
func (g *grpcServer) getGrpcOptions() []grpc.ServerOption {
if g.opts.Context == nil {
return nil
}
v := g.opts.Context.Value(grpcOptions{})
if v == nil {
return nil
}
opts, ok := v.([]grpc.ServerOption)
if !ok {
return nil
}
return opts
}
func (g *grpcServer) handler(srv interface{}, stream grpc.ServerStream) error {
if g.wg != nil {
g.wg.Add(1)
defer g.wg.Done()
}
fullMethod, ok := grpc.MethodFromServerStream(stream)
if !ok {
return grpc.Errorf(codes.Internal, "method does not exist in context")
}
serviceName, methodName, err := mgrpc.ServiceMethod(fullMethod)
if err != nil {
return status.New(codes.InvalidArgument, err.Error()).Err()
}
// get grpc metadata
gmd, ok := metadata.FromIncomingContext(stream.Context())
if !ok {
gmd = metadata.MD{}
}
// copy the metadata to go-micro.metadata
md := meta.Metadata{}
for k, v := range gmd {
md[k] = strings.Join(v, ", ")
}
// timeout for server deadline
to := md["timeout"]
// get content type
ct := defaultContentType
if ctype, ok := md["x-content-type"]; ok {
ct = ctype
}
delete(md, "x-content-type")
delete(md, "timeout")
// create new context
ctx := meta.NewContext(stream.Context(), md)
// get peer from context
if p, ok := peer.FromContext(stream.Context()); ok {
md["Remote"] = p.Addr.String()
ctx = peer.NewContext(ctx, p)
}
// set the timeout if we have it
if len(to) > 0 {
if n, err := strconv.ParseUint(to, 10, 64); err == nil {
ctx, _ = context.WithTimeout(ctx, time.Duration(n))
}
}
// process via router
if g.opts.Router != nil {
cc, err := g.newGRPCCodec(ct)
if err != nil {
return errors.InternalServerError("go.micro.server", err.Error())
}
codec := &grpcCodec{
method: fmt.Sprintf("%s.%s", serviceName, methodName),
endpoint: fmt.Sprintf("%s.%s", serviceName, methodName),
target: g.opts.Name,
s: stream,
c: cc,
}
// create a client.Request
request := &rpcRequest{
service: mgrpc.ServiceFromMethod(fullMethod),
contentType: ct,
method: fmt.Sprintf("%s.%s", serviceName, methodName),
codec: codec,
}
response := &rpcResponse{
header: make(map[string]string),
codec: codec,
}
// create a wrapped function
handler := func(ctx context.Context, req server.Request, rsp interface{}) error {
return g.opts.Router.ServeRequest(ctx, req, rsp.(server.Response))
}
// execute the wrapper for it
for i := len(g.opts.HdlrWrappers); i > 0; i-- {
handler = g.opts.HdlrWrappers[i-1](handler)
}
r := grpcRouter{handler}
// serve the actual request using the request router
if err := r.ServeRequest(ctx, request, response); err != nil {
return status.Errorf(codes.Internal, err.Error())
}
return nil
}
// process the standard request flow
g.rpc.mu.Lock()
service := g.rpc.serviceMap[serviceName]
g.rpc.mu.Unlock()
if service == nil {
return status.New(codes.Unimplemented, fmt.Sprintf("unknown service %v", service)).Err()
}
mtype := service.method[methodName]
if mtype == nil {
return status.New(codes.Unimplemented, fmt.Sprintf("unknown service %v", service)).Err()
}
// process unary
if !mtype.stream {
return g.processRequest(stream, service, mtype, ct, ctx)
}
// process stream
return g.processStream(stream, service, mtype, ct, ctx)
}
func (g *grpcServer) processRequest(stream grpc.ServerStream, service *service, mtype *methodType, ct string, ctx context.Context) error {
for {
var argv, replyv reflect.Value
// Decode the argument value.
argIsValue := false // if true, need to indirect before calling.
if mtype.ArgType.Kind() == reflect.Ptr {
argv = reflect.New(mtype.ArgType.Elem())
} else {
argv = reflect.New(mtype.ArgType)
argIsValue = true
}
// Unmarshal request
if err := stream.RecvMsg(argv.Interface()); err != nil {
return err
}
if argIsValue {
argv = argv.Elem()
}
// reply value
replyv = reflect.New(mtype.ReplyType.Elem())
function := mtype.method.Func
var returnValues []reflect.Value
cc, err := g.newGRPCCodec(ct)
if err != nil {
return errors.InternalServerError("go.micro.server", err.Error())
}
b, err := cc.Marshal(argv.Interface())
if err != nil {
return err
}
// create a client.Request
r := &rpcRequest{
service: g.opts.Name,
contentType: ct,
method: fmt.Sprintf("%s.%s", service.name, mtype.method.Name),
body: b,
payload: argv.Interface(),
}
// define the handler func
fn := func(ctx context.Context, req server.Request, rsp interface{}) error {
returnValues = function.Call([]reflect.Value{service.rcvr, mtype.prepareContext(ctx), reflect.ValueOf(argv.Interface()), reflect.ValueOf(rsp)})
// The return value for the method is an error.
if err := returnValues[0].Interface(); err != nil {
return err.(error)
}
return nil
}
// wrap the handler func
for i := len(g.opts.HdlrWrappers); i > 0; i-- {
fn = g.opts.HdlrWrappers[i-1](fn)
}
statusCode := codes.OK
statusDesc := ""
// execute the handler
if appErr := fn(ctx, r, replyv.Interface()); appErr != nil {
if err, ok := appErr.(*rpcError); ok {
statusCode = err.code
statusDesc = err.desc
} else if err, ok := appErr.(*errors.Error); ok {
statusCode = microError(err)
statusDesc = appErr.Error()
} else {
statusCode = convertCode(appErr)
statusDesc = appErr.Error()
}
return status.New(statusCode, statusDesc).Err()
}
if err := stream.SendMsg(replyv.Interface()); err != nil {
return err
}
return status.New(statusCode, statusDesc).Err()
}
}
func (g *grpcServer) processStream(stream grpc.ServerStream, service *service, mtype *methodType, ct string, ctx context.Context) error {
opts := g.opts
r := &rpcRequest{
service: opts.Name,
contentType: ct,
method: fmt.Sprintf("%s.%s", service.name, mtype.method.Name),
stream: true,
}
ss := &rpcStream{
request: r,
s: stream,
}
function := mtype.method.Func
var returnValues []reflect.Value
// Invoke the method, providing a new value for the reply.
fn := func(ctx context.Context, req server.Request, stream interface{}) error {
returnValues = function.Call([]reflect.Value{service.rcvr, mtype.prepareContext(ctx), reflect.ValueOf(stream)})
if err := returnValues[0].Interface(); err != nil {
return err.(error)
}
return nil
}
for i := len(opts.HdlrWrappers); i > 0; i-- {
fn = opts.HdlrWrappers[i-1](fn)
}
statusCode := codes.OK
statusDesc := ""
appErr := fn(ctx, r, ss)
if appErr != nil {
if err, ok := appErr.(*rpcError); ok {
statusCode = err.code
statusDesc = err.desc
} else if err, ok := appErr.(*errors.Error); ok {
statusCode = microError(err)
statusDesc = appErr.Error()
} else {
statusCode = convertCode(appErr)
statusDesc = appErr.Error()
}
}
return status.New(statusCode, statusDesc).Err()
}
func (g *grpcServer) newGRPCCodec(contentType string) (encoding.Codec, error) {
codecs := make(map[string]encoding.Codec)
if g.opts.Context != nil {
if v := g.opts.Context.Value(codecsKey{}); v != nil {
codecs = v.(map[string]encoding.Codec)
}
}
if c, ok := codecs[contentType]; ok {
return c, nil
}
if c, ok := defaultGRPCCodecs[contentType]; ok {
return c, nil
}
return nil, fmt.Errorf("Unsupported Content-Type: %s", contentType)
}
func (g *grpcServer) newCodec(contentType string) (codec.NewCodec, error) {
if cf, ok := g.opts.Codecs[contentType]; ok {
return cf, nil
}
if cf, ok := defaultRPCCodecs[contentType]; ok {
return cf, nil
}
return nil, fmt.Errorf("Unsupported Content-Type: %s", contentType)
}
func (g *grpcServer) Options() server.Options {
opts := g.opts
return opts
}
func (g *grpcServer) Init(opts ...server.Option) error {
g.configure(opts...)
return nil
}
func (g *grpcServer) NewHandler(h interface{}, opts ...server.HandlerOption) server.Handler {
return newRpcHandler(h, opts...)
}
func (g *grpcServer) Handle(h server.Handler) error {
if err := g.rpc.register(h.Handler()); err != nil {
return err
}
g.handlers[h.Name()] = h
return nil
}
func (g *grpcServer) NewSubscriber(topic string, sb interface{}, opts ...server.SubscriberOption) server.Subscriber {
return newSubscriber(topic, sb, opts...)
}
func (g *grpcServer) Subscribe(sb server.Subscriber) error {
sub, ok := sb.(*subscriber)
if !ok {
return fmt.Errorf("invalid subscriber: expected *subscriber")
}
if len(sub.handlers) == 0 {
return fmt.Errorf("invalid subscriber: no handler functions")
}
if err := validateSubscriber(sb); err != nil {
return err
}
g.Lock()
_, ok = g.subscribers[sub]
if ok {
return fmt.Errorf("subscriber %v already exists", sub)
}
g.subscribers[sub] = nil
g.Unlock()
return nil
}
func (g *grpcServer) Register() error {
// parse address for host, port
config := g.opts
var advt, host string
var port int
// check the advertise address first
// if it exists then use it, otherwise
// use the address
if len(config.Advertise) > 0 {
advt = config.Advertise
} else {
advt = config.Address
}
parts := strings.Split(advt, ":")
if len(parts) > 1 {
host = strings.Join(parts[:len(parts)-1], ":")
port, _ = strconv.Atoi(parts[len(parts)-1])
} else {
host = parts[0]
}
addr, err := addr.Extract(host)
if err != nil {
return err
}
// register service
node := &registry.Node{
Id: config.Name + "-" + config.Id,
Address: fmt.Sprintf("%s:%d", addr, port),
Metadata: config.Metadata,
}
node.Metadata["broker"] = config.Broker.String()
node.Metadata["registry"] = config.Registry.String()
node.Metadata["server"] = g.String()
node.Metadata["transport"] = g.String()
// node.Metadata["transport"] = config.Transport.String()
g.RLock()
// Maps are ordered randomly, sort the keys for consistency
var handlerList []string
for n, e := range g.handlers {
// Only advertise non internal handlers
if !e.Options().Internal {
handlerList = append(handlerList, n)
}
}
sort.Strings(handlerList)
var subscriberList []*subscriber
for e := range g.subscribers {
// Only advertise non internal subscribers
if !e.Options().Internal {
subscriberList = append(subscriberList, e)
}
}
sort.Slice(subscriberList, func(i, j int) bool {
return subscriberList[i].topic > subscriberList[j].topic
})
var endpoints []*registry.Endpoint
for _, n := range handlerList {
endpoints = append(endpoints, g.handlers[n].Endpoints()...)
}
for _, e := range subscriberList {
endpoints = append(endpoints, e.Endpoints()...)
}
g.RUnlock()
service := &registry.Service{
Name: config.Name,
Version: config.Version,
Nodes: []*registry.Node{node},
Endpoints: endpoints,
}
g.Lock()
registered := g.registered
g.Unlock()
if !registered {
log.Logf("Registering node: %s", node.Id)
}
// create registry options
rOpts := []registry.RegisterOption{registry.RegisterTTL(config.RegisterTTL)}
if err := config.Registry.Register(service, rOpts...); err != nil {
return err
}
// already registered? don't need to register subscribers
if registered {
return nil
}
g.Lock()
defer g.Unlock()
g.registered = true
for sb, _ := range g.subscribers {
handler := g.createSubHandler(sb, g.opts)
var opts []broker.SubscribeOption
if queue := sb.Options().Queue; len(queue) > 0 {
opts = append(opts, broker.Queue(queue))
}
if !sb.Options().AutoAck {
opts = append(opts, broker.DisableAutoAck())
}
sub, err := config.Broker.Subscribe(sb.Topic(), handler, opts...)
if err != nil {
return err
}
g.subscribers[sb] = []broker.Subscriber{sub}
}
return nil
}
func (g *grpcServer) Deregister() error {
config := g.opts
var advt, host string
var port int
// check the advertise address first
// if it exists then use it, otherwise
// use the address
if len(config.Advertise) > 0 {
advt = config.Advertise
} else {
advt = config.Address
}
parts := strings.Split(advt, ":")
if len(parts) > 1 {
host = strings.Join(parts[:len(parts)-1], ":")
port, _ = strconv.Atoi(parts[len(parts)-1])
} else {
host = parts[0]
}
addr, err := addr.Extract(host)
if err != nil {
return err
}
node := &registry.Node{
Id: config.Name + "-" + config.Id,
Address: fmt.Sprintf("%s:%d", addr, port),
}
service := &registry.Service{
Name: config.Name,
Version: config.Version,
Nodes: []*registry.Node{node},
}
log.Logf("Deregistering node: %s", node.Id)
if err := config.Registry.Deregister(service); err != nil {
return err
}
g.Lock()
if !g.registered {
g.Unlock()
return nil
}
g.registered = false
for sb, subs := range g.subscribers {
for _, sub := range subs {
log.Logf("Unsubscribing from topic: %s", sub.Topic())
sub.Unsubscribe()
}
g.subscribers[sb] = nil
}
g.Unlock()
return nil
}
func (g *grpcServer) Start() error {
registerDebugHandler(g)
config := g.opts
// micro: config.Transport.Listen(config.Address)
ts, err := net.Listen("tcp", config.Address)
if err != nil {
return err
}
log.Logf("Server [grpc] Listening on %s", ts.Addr().String())
g.Lock()
g.opts.Address = ts.Addr().String()
g.Unlock()
// connect to the broker
if err := config.Broker.Connect(); err != nil {
return err
}
baddr := strings.Join(config.Broker.Options().Addrs, ",")
bname := config.Broker.String()
log.Logf("Broker [%s] Listening on %s", bname, baddr)
// announce self to the world
if err := g.Register(); err != nil {
log.Log("Server register error: ", err)
}
// micro: go ts.Accept(s.accept)
go func() {
if err := g.srv.Serve(ts); err != nil {
log.Log("gRPC Server start error: ", err)
}
}()
go func() {
t := new(time.Ticker)
// only process if it exists
if g.opts.RegisterInterval > time.Duration(0) {
// new ticker
t = time.NewTicker(g.opts.RegisterInterval)
}
// return error chan
var ch chan error
Loop:
for {
select {
// register self on interval
case <-t.C:
if err := g.Register(); err != nil {
log.Log("Server register error: ", err)
}
// wait for exit
case ch = <-g.exit:
break Loop
}
}
// deregister self
if err := g.Deregister(); err != nil {
log.Log("Server deregister error: ", err)
}
// wait for waitgroup
if g.wg != nil {
g.wg.Wait()
}
// stop the grpc server
g.srv.GracefulStop()
// close transport
ch <- nil
// disconnect broker
config.Broker.Disconnect()
}()
return nil
}
func (g *grpcServer) Stop() error {
ch := make(chan error)
g.exit <- ch
return <-ch
}
func (g *grpcServer) String() string {
return "grpc"
}
func NewServer(opts ...server.Option) server.Server {
return newGRPCServer(opts...)
}