Export the ability of custom ConnHandlers and a lot of improvements that allow externals package to interact with neffos structs-to-events feature such as Iris' new v11.2+ fully featured MVC websocket controller

Author: kataras

client.go

@@ -84,7 +84,7 @@ func Dial(ctx context.Context, dial Dialer, url string, connHandler ConnHandler)
 		connHandler = Namespaces{}
 	}
 
-	c := newConn(underline, connHandler.getNamespaces())
+	c := newConn(underline, connHandler.GetNamespaces())
 	readTimeout, writeTimeout := getTimeouts(connHandler)
 	c.readTimeout = readTimeout
 	c.writeTimeout = writeTimeout

conn_handler.go

@@ -6,11 +6,11 @@ import (
 	"time"
 )
 
-// ConnHandler is the interface which
-// `Events`, `Namespaces` and `WithTimeout` are implement.
-// It's exported just to be used on the `Dial`(client) and `New` (server) functions.
+// ConnHandler is the interface which namespaces and events can be retrieved through.
+// Built-in ConnHandlers are the`Events`, `Namespaces`, `WithTimeout` and `NewStruct`.
+// Users of this are the `Dial`(client) and `New` (server) functions.
 type ConnHandler interface {
-	getNamespaces() Namespaces
+	GetNamespaces() Namespaces
 }
 
 var (
@@ -31,7 +31,8 @@ var (
 // See `Namespaces`, `New` and `Dial` too.
 type Events map[string]MessageHandlerFunc
 
-func (e Events) getNamespaces() Namespaces {
+// GetNamespaces returns an empty namespace with the "e" Events.
+func (e Events) GetNamespaces() Namespaces {
 	return Namespaces{"": e}
 }
 
@@ -55,7 +56,8 @@ func (e Events) fireEvent(c *NSConn, msg Message) error {
 // See `WithTimeout`, `New` and `Dial` too.
 type Namespaces map[string]Events
 
-func (nss Namespaces) getNamespaces() Namespaces { return nss }
+// GetNamespaces just returns the "nss" namespaces.
+func (nss Namespaces) GetNamespaces() Namespaces { return nss }
 
 // WithTimeout completes the `ConnHandler` interface.
 // Can be used to register namespaces and events or just events on an empty namespace
@@ -70,8 +72,10 @@ type WithTimeout struct {
 	Events     Events
 }
 
-func (t WithTimeout) getNamespaces() Namespaces {
-	return JoinConnHandlers(t.Namespaces, t.Events).getNamespaces()
+// GetNamespaces returns combined namespaces from "Namespaces" and "Events" fields
+// with read and write timeouts from "ReadTimeout" and "WriteTimeout" fields of "t".
+func (t WithTimeout) GetNamespaces() Namespaces {
+	return JoinConnHandlers(t.Namespaces, t.Events).GetNamespaces()
 }
 
 func getTimeouts(h ConnHandler) (readTimeout time.Duration, writeTimeout time.Duration) {
@@ -103,6 +107,9 @@ type Struct struct {
 	eventMatcher              EventMatcherFunc
 	readTimeout, writeTimeout time.Duration
 
+	// This field is set when external dependency injection system is used.
+	injector StructInjector
+
 	events Events
 }
 
@@ -157,6 +164,18 @@ func (s *Struct) SetTimeouts(read, write time.Duration) *Struct {
 	return s
 }
 
+// SetInjector sets a custom injector and overrides the neffos default behavior
+// on dynamic structs.
+// The "fn" should handle to fill static fields and the NSConn.
+// This "fn" will only be called when dynamic struct "ptr" is passed
+// on the `NewStruct`.
+// The caller should return a
+// valid type of "ptr" reflect.Value.
+func (s *Struct) SetInjector(fn StructInjector) *Struct {
+	s.injector = fn
+	return s
+}
+
 // NewStruct returns a new Struct value instance type of ConnHandler.
 // The "ptr" should be a pointer to a struct.
 // This function is used when you want to convert a structure to
@@ -173,7 +192,27 @@ func (s *Struct) SetTimeouts(read, write time.Duration) *Struct {
 //
 // Note that this method has a tiny performance cost when an event's callback's logic has small footprint.
 func NewStruct(ptr interface{}) *Struct {
-	typ := reflect.TypeOf(ptr) // use for methods with receiver Ptr.
+	if ptr == nil {
+		panic("NewStruct: value is nil")
+	}
+
+	if s, ok := ptr.(*Struct); ok { // if it's already a *Struct then just return it.
+		return s
+	}
+
+	var v reflect.Value // use for methods with receiver Ptr.
+	if rValue, ok := ptr.(reflect.Value); ok {
+		v = rValue
+	} else {
+		v = reflect.ValueOf(ptr)
+	}
+
+	if !v.IsValid() {
+		panic("NewStruct: value is not a valid one")
+	}
+
+	typ := v.Type() // use for methods with receiver Ptr.
+
 	if typ.Kind() != reflect.Ptr {
 		panic("NewStruct: value should be a pointer")
 	}
@@ -186,11 +225,6 @@ func NewStruct(ptr interface{}) *Struct {
 		panic("NewStruct: value does not points to a struct")
 	}
 
-	v := reflect.ValueOf(ptr) // use for methods with receiver Ptr.
-	if !v.IsValid() {
-		panic("NewStruct: value is not a valid one")
-	}
-
 	n := typ.NumMethod()
 	_, hasNamespaceMethod := typ.MethodByName("Namespace")
 	if n == 0 || (n == 1 && hasNamespaceMethod) {
@@ -212,11 +246,13 @@ func (s *Struct) Events() Events {
 		return s.events
 	}
 
-	s.events = makeEventsFromStruct(s.ptr, s.eventMatcher)
+	s.events = makeEventsFromStruct(s.ptr, s.eventMatcher, s.injector)
 	return s.events
 }
 
-func (s *Struct) getNamespaces() Namespaces { // completes the `ConnHandler` interface.
+// GetNamespaces creates and returns Namespaces based on the
+// pointer to struct value provided by the "s".
+func (s *Struct) GetNamespaces() Namespaces { // completes the `ConnHandler` interface.
 	if s.namespace == "" {
 		s.namespace, _ = resolveStructNamespace(s.ptr)
 	}
@@ -233,7 +269,7 @@ func JoinConnHandlers(connHandlers ...ConnHandler) ConnHandler {
 	namespaces := Namespaces{}
 
 	for _, h := range connHandlers {
-		nss := h.getNamespaces()
+		nss := h.GetNamespaces()
 		if len(nss) > 0 {
 			for namespace, events := range nss {
 				if events == nil {

conn_handler_struct_test.go

@@ -23,7 +23,7 @@ func TestConnHandlerStructStatic(t *testing.T) {
 	v := new(testStructStatic)
 	v.Err = fmt.Errorf("from static")
 	s := NewStruct(v)
-	nss := s.getNamespaces()
+	nss := s.GetNamespaces()
 
 	if expected, got := v.Namespace(), s.namespace; expected != got {
 		t.Fatalf("expected namespace to be: %s but got: %s", expected, got)
@@ -56,7 +56,7 @@ func TestConnHandlerStructDynamic(t *testing.T) {
 		StaticFieldErr: fmt.Errorf("a static field which should be set on each new testStructDynamic"),
 	}
 	s := NewStruct(v)
-	nss := s.getNamespaces()
+	nss := s.GetNamespaces()
 
 	nsConn := &NSConn{namespace: s.namespace}
 	nss[s.namespace][OnNamespaceConnect](nsConn, Message{Namespace: s.namespace})
@@ -84,7 +84,7 @@ func TestConnHandlerStructDynamicEmbedded(t *testing.T) {
 	v := new(testStructDynamicEmbedded)
 	s := NewStruct(v)
 	s.namespace = "default"
-	nss := s.getNamespaces()
+	nss := s.GetNamespaces()
 
 	nsConn := &NSConn{namespace: s.namespace}
 	nss[s.namespace][OnNamespaceConnect](nsConn, Message{Namespace: s.namespace})

conn_namespace.go

@@ -2,8 +2,8 @@ package neffos
 
 import (
 	"context"
+	"reflect"
 	"sync"
-	"sync/atomic"
 )
 
 // NSConn describes a connection connected to a specific namespace,
@@ -25,9 +25,9 @@ type NSConn struct {
 	rooms      map[string]*Room
 	roomsMutex sync.RWMutex
 
-	// Value is just a temporarily atomic value.
+	// value is just a temporarily value.
 	// Storage across event callbacks for this namespace.
-	Value atomic.Value
+	value reflect.Value
 }
 
 func newNSConn(c *Conn, namespace string, events Events) *NSConn {

debug.go

@@ -32,11 +32,12 @@ func EnableDebug(printer interface{}) {
 	}
 
 	if printer == nil {
-		printer = log.New(os.Stderr, "| neffos | ", 0)
+		logger := log.New(os.Stderr, "| neffos | ", 0)
+		printer = logger
+		logger.Println("debug mode is set")
 	}
 
 	debugPrinter = printer
-	debugf("debug mode is set")
 }
 
 type (

reflect.go

@@ -2,6 +2,7 @@ package neffos
 
 import (
 	"reflect"
+	"strings"
 )
 
 func indirectType(typ reflect.Type) reflect.Type {
@@ -109,8 +110,8 @@ func resolveStructNamespace(v reflect.Value) (string, bool) {
 	if ok {
 		if getNamespace, ok := v.Method(method.Index).Interface().(func() string); ok {
 			namespace := getNamespace()
-			debugf("set namespace [%s] from method [%s.%s]", func() dargs {
-				return dargs{namespace, indirectType(typ).Name(), method.Name}
+			debugf("Set namespace [\"%s\"] from method [%s.%s]", func() dargs {
+				return dargs{namespace, nameOf(typ), method.Name}
 			})
 
 			return namespace, true
@@ -123,8 +124,8 @@ func resolveStructNamespace(v reflect.Value) (string, bool) {
 	if f, ok := typ.FieldByNameFunc(func(s string) bool { return s == "Namespace" }); ok {
 		if f.Type.Kind() == reflect.String {
 			namespace := v.Field(f.Index[0]).String()
-			debugf("set namespace [%s] from field [%s.%s]", func() dargs {
-				return dargs{namespace, typ.Name(), f.Name}
+			debugf("Set namespace [\"%s\"] from field [%s.%s]", func() dargs {
+				return dargs{namespace, nameOf(typ), f.Name}
 			})
 			return namespace, true
 		}
@@ -204,15 +205,27 @@ func makeEventFromMethod(v reflect.Value, method reflect.Method, eventMatcher Ev
 		// the NSConn exists on the "controller" itself which is set dynamically.
 		cb = func(c *NSConn, msg Message) error {
 			// load an existing instance which contains the same "c".
-			cachePtr := c.Value.Load().(reflect.Value)
-			return cachePtr.Method(method.Index).Interface().(func(Message) error)(msg)
+			return c.value.Method(method.Index).Interface().(func(Message) error)(msg)
 		}
 	}
 
 	return
 }
 
-func makeEventsFromStruct(v reflect.Value, eventMatcher EventMatcherFunc) Events {
+// StructInjector is a type which injects a dynamic struct value.
+// See `Struct.SetInjector` for more.
+type StructInjector func(structType reflect.Type, nsConn *NSConn) (structValue reflect.Value)
+
+func nameOf(structType reflect.Type) string {
+	structType = indirectType(structType)
+
+	typName := structType.Name()
+	pkgPath := structType.PkgPath()
+	fullname := pkgPath[strings.LastIndexByte(pkgPath, '/')+1:] + "." + typName
+	return fullname
+}
+
+func makeEventsFromStruct(v reflect.Value, eventMatcher EventMatcherFunc, injector StructInjector) Events {
 	events := make(Events, 0)
 
 	typ := v.Type()
@@ -233,60 +246,59 @@ func makeEventsFromStruct(v reflect.Value, eventMatcher EventMatcherFunc) Events
 			continue
 		}
 
-		debugf("event [%s] is handled by [%s.%s]", func() dargs {
-			return dargs{eventName, indirectType(typ).Name(), method.Name}
+		debugf("Event [\"%s\"] is handled by [%s.%s] method", func() dargs {
+			return dargs{eventName, nameOf(typ), method.Name}
 		})
 
 		events[eventName] = cb
 	}
 
 	if nsConnFieldIndex != -1 {
-		// if it's a dynamic.
 		typ = indirectType(typ)
 
-		cb, hasNamespaceConnect := events[OnNamespaceConnect]
-		staticFields := getNonZeroFields(v)
-
-		// debugf("field [%s.%s] will be automatically re-filled with [%T(%s)]", func(fidx int, f reflect.Value) dargs {
-		// 	fval := f.Interface()
-		// 	return dargs{typ.Name(), typ.Field(fidx).Name, fval, fval}
-		// }).forEach(staticFields)
-
-		debugEach(staticFields, func(idx int, f reflect.Value) {
-			fval := f.Interface()
-			fname := typ.Field(idx).Name
-			if fname == "Namespace" {
-				return // let's no log this as user field because
-				// it's optionally used to provide a namespace on NewStruct.getNamespaces().
-			}
+		var staticFields map[int]reflect.Value
 
-			debugf("field [%s.%s] marked as static on value [%v]", typ.Name(), fname, fval)
-		})
+		if injector == nil {
+			// maybe this should be added no matter what, I have to check
+			// some things in our company's production server first.
+			staticFields = getNonZeroFields(v)
+
+			debugEach(staticFields, func(idx int, f reflect.Value) {
+				fval := f.Interface()
+				fname := typ.Field(idx).Name
+				if fname == "Namespace" {
+					// let's no log this as user field because
+					// it's optionally used to provide a namespace on NewStruct.GetNamespaces().
+					return
+				}
+
+				debugf("Field [%s.%s] marked as static on value [%v]", nameOf(typ), fname, fval)
+			})
+
+			injector = func(typ reflect.Type, nsConn *NSConn) reflect.Value {
+				return reflect.New(typ)
+			}
+		}
 
-		// if debugEnabled() {
-		// 	for fidx, f := range staticFields {
-		// 		fval := f.Interface()
-		// 		debugf(, typ.Name(), typ.Field(fidx).Name, fval, fval)
-		// 	}
-		// }
+		cb, hasNamespaceConnect := events[OnNamespaceConnect]
 
 		events[OnNamespaceConnect] = func(c *NSConn, msg Message) error {
-			// create a new elem instance.
-			cachePtr := reflect.New(typ)
+			cachePtr := injector(typ, c)
 			cacheElem := cachePtr.Elem()
 
 			// set the NSConn dynamic field.
 			cacheElem.Field(nsConnFieldIndex).Set(reflect.ValueOf(c))
+
 			if staticFields != nil {
-				// set any static fields.
+				// set any static fields if default injector (see above).
 				for findex, fvalue := range staticFields {
 					cacheElem.Field(findex).Set(fvalue)
 				}
 			}
 
 			// Store it for the rest of the events inside
 			// this namespace of that specific connection.
-			c.Value.Store(cachePtr)
+			c.value = cachePtr
 
 			if hasNamespaceConnect {
 				return cb(c, msg)

server.go

@@ -86,7 +86,7 @@ func New(upgrader Upgrader, connHandler ConnHandler) *Server {
 
 	s := &Server{
 		upgrader:     upgrader,
-		namespaces:   connHandler.getNamespaces(),
+		namespaces:   connHandler.GetNamespaces(),
 		readTimeout:  readTimeout,
 		writeTimeout: writeTimeout,
 		connections:  make(map[*Conn]struct{}),