http server supports subscriber

buffer.go

@@ -0,0 +1,14 @@
+package http
+
+import (
+	"bytes"
+)
+
+type buffer struct {
+	*bytes.Buffer
+}
+
+func (b *buffer) Close() error {
+	b.Buffer.Reset()
+	return nil
+}

extractor.go

@@ -1,12 +1,13 @@
 package http
 
 import (
+	"fmt"
+	"reflect"
 	"strconv"
 	"strings"
 
 	"github.com/micro/go-micro/registry"
 	"github.com/micro/go-micro/server"
-
 	"github.com/micro/util/go/lib/addr"
 )
 
@@ -48,3 +49,111 @@ func serviceDef(opts server.Options) *registry.Service {
 		Nodes:   []*registry.Node{node},
 	}
 }
+
+func extractValue(v reflect.Type, d int) *registry.Value {
+	if d == 3 {
+		return nil
+	}
+	if v == nil {
+		return nil
+	}
+
+	if v.Kind() == reflect.Ptr {
+		v = v.Elem()
+	}
+
+	arg := &registry.Value{
+		Name: v.Name(),
+		Type: v.Name(),
+	}
+
+	switch v.Kind() {
+	case reflect.Struct:
+		for i := 0; i < v.NumField(); i++ {
+			f := v.Field(i)
+			val := extractValue(f.Type, d+1)
+			if val == nil {
+				continue
+			}
+
+			// if we can find a json tag use it
+			if tags := f.Tag.Get("json"); len(tags) > 0 {
+				parts := strings.Split(tags, ",")
+				val.Name = parts[0]
+			}
+
+			// if there's no name default it
+			if len(val.Name) == 0 {
+				val.Name = v.Field(i).Name
+			}
+
+			arg.Values = append(arg.Values, val)
+		}
+	case reflect.Slice:
+		p := v.Elem()
+		if p.Kind() == reflect.Ptr {
+			p = p.Elem()
+		}
+		arg.Type = "[]" + p.Name()
+		val := extractValue(v.Elem(), d+1)
+		if val != nil {
+			arg.Values = append(arg.Values, val)
+		}
+	}
+
+	return arg
+}
+
+func extractEndpoint(method reflect.Method) *registry.Endpoint {
+	if method.PkgPath != "" {
+		return nil
+	}
+
+	var rspType, reqType reflect.Type
+	var stream bool
+	mt := method.Type
+
+	switch mt.NumIn() {
+	case 3:
+		reqType = mt.In(1)
+		rspType = mt.In(2)
+	case 4:
+		reqType = mt.In(2)
+		rspType = mt.In(3)
+	default:
+		return nil
+	}
+
+	// are we dealing with a stream?
+	switch rspType.Kind() {
+	case reflect.Func, reflect.Interface:
+		stream = true
+	}
+
+	request := extractValue(reqType, 0)
+	response := extractValue(rspType, 0)
+
+	return &registry.Endpoint{
+		Name:     method.Name,
+		Request:  request,
+		Response: response,
+		Metadata: map[string]string{
+			"stream": fmt.Sprintf("%v", stream),
+		},
+	}
+}
+
+func extractSubValue(typ reflect.Type) *registry.Value {
+	var reqType reflect.Type
+	switch typ.NumIn() {
+	case 1:
+		reqType = typ.In(0)
+	case 2:
+		reqType = typ.In(1)
+	case 3:
+		reqType = typ.In(2)
+	default:
+		return nil
+	}
+	return extractValue(reqType, 0)
+}

http.go

@@ -3,28 +3,54 @@ package http
 
 import (
 	"errors"
+	"fmt"
 	"net"
 	"net/http"
+	"sort"
 	"sync"
 
 	"github.com/micro/go-log"
-	"github.com/micro/go-micro/cmd"
-	"github.com/micro/go-micro/registry"
+	"github.com/micro/go-micro/broker"
 	"github.com/micro/go-micro/server"
+	"github.com/micro/go-micro/cmd"
+	"github.com/micro/go-micro/codec"
+	"github.com/micro/go-micro/registry"
+	"github.com/micro/go-plugins/codec/jsonrpc"
+	"github.com/micro/go-plugins/codec/protorpc"
 )
 
+var (
+	defaultCodecs = map[string]codec.NewCodec{
+		"application/json":         jsonrpc.NewCodec,
+		"application/json-rpc":     jsonrpc.NewCodec,
+		"application/protobuf":     protorpc.NewCodec,
+		"application/proto-rpc":    protorpc.NewCodec,
+		"application/octet-stream": protorpc.NewCodec,
+	}
+)
 type httpServer struct {
 	sync.Mutex
 	opts         server.Options
 	hd           server.Handler
 	exit         chan chan error
 	registerOnce sync.Once
+	subscribers  map[*subscriber][]broker.Subscriber
 }
 
 func init() {
 	cmd.DefaultServers["http"] = NewServer
 }
 
+func (h *httpServer) newCodec(contentType string) (codec.NewCodec, error) {
+	if cf, ok := h.opts.Codecs[contentType]; ok {
+		return cf, nil
+	}
+	if cf, ok := defaultCodecs[contentType]; ok {
+		return cf, nil
+	}
+	return nil, fmt.Errorf("Unsupported Content-Type: %s", contentType)
+}
+
 func (h *httpServer) Options() server.Options {
 	h.Lock()
 	opts := h.opts
@@ -79,20 +105,30 @@ func (h *httpServer) NewHandler(handler interface{}, opts ...server.HandlerOptio
 }
 
 func (h *httpServer) NewSubscriber(topic string, handler interface{}, opts ...server.SubscriberOption) server.Subscriber {
-	var options server.SubscriberOptions
-	for _, o := range opts {
-		o(&options)
-	}
-
-	return &httpSubscriber{
-		opts:  options,
-		topic: topic,
-		hd:    handler,
-	}
+	return newSubscriber(topic, handler, opts...)
 }
 
-func (h *httpServer) Subscribe(s server.Subscriber) error {
-	return errors.New("subscribe is not supported")
+func (h *httpServer) 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
+	}
+
+	h.Lock()
+	defer h.Unlock()
+	_, ok = h.subscribers[sub]
+	if ok {
+		return fmt.Errorf("subscriber %v already exists", h)
+	}
+	h.subscribers[sub] = nil
+	return nil
 }
 
 func (h *httpServer) Register() error {
@@ -104,12 +140,42 @@ func (h *httpServer) Register() error {
 	service := serviceDef(opts)
 	service.Endpoints = eps
 
+	h.Lock()
+	var subscriberList []*subscriber
+	for e := range h.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
+	})
+	for _, e := range subscriberList {
+		service.Endpoints = append(service.Endpoints, e.Endpoints()...)
+	}
+	h.Unlock()
+
 	rOpts := []registry.RegisterOption{
 		registry.RegisterTTL(opts.RegisterTTL),
 	}
 
 	h.registerOnce.Do(func() {
 		log.Logf("Registering node: %s", opts.Name+"-"+opts.Id)
+
+		for sb, _ := range h.subscribers {
+			handler := h.createSubHandler(sb, opts)
+			var subOpts []broker.SubscribeOption
+			if queue := sb.Options().Queue; len(queue) > 0 {
+				subOpts = append(subOpts, broker.Queue(queue))
+			}
+			sub, err := opts.Broker.Subscribe(sb.Topic(), handler, subOpts...)
+			if err != nil {
+				log.Logf("Registering subscriber: %s, err: %s", sb.Topic, err)
+				return
+			}
+			h.subscribers[sb] = []broker.Subscriber{sub}
+		}
 	})
 
 	return opts.Registry.Register(service, rOpts...)

message.go

@@ -0,0 +1,19 @@
+package http
+
+type rpcMessage struct {
+	topic       string
+	contentType string
+	payload     interface{}
+}
+
+func (r *rpcMessage) ContentType() string {
+	return r.contentType
+}
+
+func (r *rpcMessage) Topic() string {
+	return r.topic
+}
+
+func (r *rpcMessage) Payload() interface{} {
+	return r.payload
+}

subscriber.go

@@ -1,28 +1,292 @@
 package http
 
 import (
+	"bytes"
+	"context"
+	"fmt"
+	"reflect"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/micro/go-micro/broker"
+	"github.com/micro/go-micro/codec"
+	"github.com/micro/go-micro/metadata"
 	"github.com/micro/go-micro/registry"
 	"github.com/micro/go-micro/server"
 )
 
-type httpSubscriber struct {
-	opts  server.SubscriberOptions
+const (
+	subSig = "func(context.Context, interface{}) error"
+)
+
+var typeOfError = reflect.TypeOf((*error)(nil)).Elem()
+
+type handler struct {
+	method  reflect.Value
+	reqType reflect.Type
+	ctxType reflect.Type
+}
+
+type subscriber struct {
 	topic      string
-	hd    interface{}
+	rcvr       reflect.Value
+	typ        reflect.Type
+	subscriber interface{}
+	handlers   []*handler
+	endpoints  []*registry.Endpoint
+	opts       server.SubscriberOptions
 }
 
-func (h *httpSubscriber) Topic() string {
-	return h.topic
+// Is this an exported - upper case - name?
+func isExported(name string) bool {
+	rune, _ := utf8.DecodeRuneInString(name)
+	return unicode.IsUpper(rune)
 }
 
-func (h *httpSubscriber) Subscriber() interface{} {
-	return h.hd
+// Is this type exported or a builtin?
+func isExportedOrBuiltinType(t reflect.Type) bool {
+	for t.Kind() == reflect.Ptr {
+		t = t.Elem()
+	}
+	// PkgPath will be non-empty even for an exported type,
+	// so we need to check the type name as well.
+	return isExported(t.Name()) || t.PkgPath() == ""
 }
 
-func (h *httpSubscriber) Endpoints() []*registry.Endpoint {
-	return []*registry.Endpoint{}
+func newSubscriber(topic string, sub interface{}, opts ...server.SubscriberOption) server.Subscriber {
+	var options server.SubscriberOptions
+	for _, o := range opts {
+		o(&options)
+	}
+
+	var endpoints []*registry.Endpoint
+	var handlers []*handler
+
+	if typ := reflect.TypeOf(sub); typ.Kind() == reflect.Func {
+		h := &handler{
+			method: reflect.ValueOf(sub),
+		}
+
+		switch typ.NumIn() {
+		case 1:
+			h.reqType = typ.In(0)
+		case 2:
+			h.ctxType = typ.In(0)
+			h.reqType = typ.In(1)
+		}
+
+		handlers = append(handlers, h)
+
+		endpoints = append(endpoints, &registry.Endpoint{
+			Name:    "Func",
+			Request: extractSubValue(typ),
+			Metadata: map[string]string{
+				"topic":      topic,
+				"subscriber": "true",
+			},
+		})
+	} else {
+		hdlr := reflect.ValueOf(sub)
+		name := reflect.Indirect(hdlr).Type().Name()
+
+		for m := 0; m < typ.NumMethod(); m++ {
+			method := typ.Method(m)
+			h := &handler{
+				method: method.Func,
+			}
+
+			switch method.Type.NumIn() {
+			case 2:
+				h.reqType = method.Type.In(1)
+			case 3:
+				h.ctxType = method.Type.In(1)
+				h.reqType = method.Type.In(2)
+			}
+
+			handlers = append(handlers, h)
+
+			endpoints = append(endpoints, &registry.Endpoint{
+				Name:    name + "." + method.Name,
+				Request: extractSubValue(method.Type),
+				Metadata: map[string]string{
+					"topic":      topic,
+					"subscriber": "true",
+				},
+			})
+		}
+	}
+
+	return &subscriber{
+		rcvr:       reflect.ValueOf(sub),
+		typ:        reflect.TypeOf(sub),
+		topic:      topic,
+		subscriber: sub,
+		handlers:   handlers,
+		endpoints:  endpoints,
+		opts:       options,
+	}
 }
 
-func (h *httpSubscriber) Options() server.SubscriberOptions {
-	return h.opts
+func validateSubscriber(sub server.Subscriber) error {
+	typ := reflect.TypeOf(sub.Subscriber())
+	var argType reflect.Type
+
+	if typ.Kind() == reflect.Func {
+		name := "Func"
+		switch typ.NumIn() {
+		case 2:
+			argType = typ.In(1)
+		default:
+			return fmt.Errorf("subscriber %v takes wrong number of args: %v required signature %s", name, typ.NumIn(), subSig)
+		}
+		if !isExportedOrBuiltinType(argType) {
+			return fmt.Errorf("subscriber %v argument type not exported: %v", name, argType)
+		}
+		if typ.NumOut() != 1 {
+			return fmt.Errorf("subscriber %v has wrong number of outs: %v require signature %s",
+				name, typ.NumOut(), subSig)
+		}
+		if returnType := typ.Out(0); returnType != typeOfError {
+			return fmt.Errorf("subscriber %v returns %v not error", name, returnType.String())
+		}
+	} else {
+		hdlr := reflect.ValueOf(sub.Subscriber())
+		name := reflect.Indirect(hdlr).Type().Name()
+
+		for m := 0; m < typ.NumMethod(); m++ {
+			method := typ.Method(m)
+
+			switch method.Type.NumIn() {
+			case 3:
+				argType = method.Type.In(2)
+			default:
+				return fmt.Errorf("subscriber %v.%v takes wrong number of args: %v required signature %s",
+					name, method.Name, method.Type.NumIn(), subSig)
+			}
+
+			if !isExportedOrBuiltinType(argType) {
+				return fmt.Errorf("%v argument type not exported: %v", name, argType)
+			}
+			if method.Type.NumOut() != 1 {
+				return fmt.Errorf(
+					"subscriber %v.%v has wrong number of outs: %v require signature %s",
+					name, method.Name, method.Type.NumOut(), subSig)
+			}
+			if returnType := method.Type.Out(0); returnType != typeOfError {
+				return fmt.Errorf("subscriber %v.%v returns %v not error", name, method.Name, returnType.String())
+			}
+		}
+	}
+
+	return nil
+}
+
+func (s *httpServer) createSubHandler(sb *subscriber, opts server.Options) broker.Handler {
+	return func(p broker.Publication) error {
+		msg := p.Message()
+		ct := msg.Header["Content-Type"]
+		cf, err := s.newCodec(ct)
+		if err != nil {
+			return err
+		}
+
+		hdr := make(map[string]string)
+		for k, v := range msg.Header {
+			hdr[k] = v
+		}
+		delete(hdr, "Content-Type")
+		ctx := metadata.NewContext(context.Background(), hdr)
+
+		results := make(chan error, len(sb.handlers))
+
+		for i := 0; i < len(sb.handlers); i++ {
+			handler := sb.handlers[i]
+
+			var isVal bool
+			var req reflect.Value
+
+			if handler.reqType.Kind() == reflect.Ptr {
+				req = reflect.New(handler.reqType.Elem())
+			} else {
+				req = reflect.New(handler.reqType)
+				isVal = true
+			}
+			if isVal {
+				req = req.Elem()
+			}
+
+			b := &buffer{bytes.NewBuffer(msg.Body)}
+			co := cf(b)
+			defer co.Close()
+
+			if err := co.ReadHeader(&codec.Message{}, codec.Publication); err != nil {
+				return err
+			}
+
+			if err := co.ReadBody(req.Interface()); err != nil {
+				return err
+			}
+
+			fn := func(ctx context.Context, msg server.Message) error {
+				var vals []reflect.Value
+				if sb.typ.Kind() != reflect.Func {
+					vals = append(vals, sb.rcvr)
+				}
+				if handler.ctxType != nil {
+					vals = append(vals, reflect.ValueOf(ctx))
+				}
+
+				vals = append(vals, reflect.ValueOf(msg.Payload()))
+
+				returnValues := handler.method.Call(vals)
+				if err := returnValues[0].Interface(); err != nil {
+					return err.(error)
+				}
+				return nil
+			}
+
+			for i := len(opts.SubWrappers); i > 0; i-- {
+				fn = opts.SubWrappers[i-1](fn)
+			}
+
+			go func() {
+				results <- fn(ctx, &rpcMessage{
+					topic:       sb.topic,
+					contentType: ct,
+					payload:     req.Interface(),
+				})
+			}()
+		}
+
+		var errors []string
+
+		for i := 0; i < len(sb.handlers); i++ {
+			if err := <-results; err != nil {
+				errors = append(errors, err.Error())
+			}
+		}
+
+		if len(errors) > 0 {
+			return fmt.Errorf("subscriber error: %s", strings.Join(errors, "\n"))
+		}
+
+		return nil
+	}
+}
+
+func (s *subscriber) Topic() string {
+	return s.topic
+}
+
+func (s *subscriber) Subscriber() interface{} {
+	return s.subscriber
+}
+
+func (s *subscriber) Endpoints() []*registry.Endpoint {
+	return s.endpoints
+}
+
+func (s *subscriber) Options() server.SubscriberOptions {
+	return s.opts
 }