Fixed and improved events management.

[src/xds/xds-server.git] / lib / xdsserver / events.go

diff --git a/lib/xdsserver/events.go b/lib/xdsserver/events.go
new file mode 100644 (file)
index 0000000..007b89a
--- /dev/null
+++ b/lib/xdsserver/events.go
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2017 "IoT.bzh"
+ * Author Sebastien Douheret <sebastien@iot.bzh>
+ *
+ * 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 xdsserver
+
+import (
+       "fmt"
+       "time"
+
+       "github.com/iotbzh/xds-server/lib/xsapiv1"
+)
+
+// EventDef Definition on one event
+type EventDef struct {
+       sids map[string]int
+}
+
+// Events Hold registered events per context
+type Events struct {
+       *Context
+       eventsMap map[string]*EventDef
+}
+
+// NewEvents creates an instance of Events
+func NewEvents(ctx *Context) *Events {
+       evMap := make(map[string]*EventDef)
+       for _, ev := range xsapiv1.EVTAllList {
+               evMap[ev] = &EventDef{
+                       sids: make(map[string]int),
+               }
+       }
+       return &Events{
+               Context:   ctx,
+               eventsMap: evMap,
+       }
+}
+
+// GetList returns the list of all supported events
+func (e *Events) GetList() []string {
+       return xsapiv1.EVTAllList
+}
+
+// Register Used by a client/session to register to a specific (or all) event(s)
+func (e *Events) Register(evName, sessionID string) error {
+       evs := xsapiv1.EVTAllList
+       if evName != xsapiv1.EVTAll {
+               if _, ok := e.eventsMap[evName]; !ok {
+                       return fmt.Errorf("Unsupported event type name")
+               }
+               evs = []string{evName}
+       }
+       for _, ev := range evs {
+               e.eventsMap[ev].sids[sessionID]++
+       }
+       return nil
+}
+
+// UnRegister Used by a client/session to un-register event(s)
+func (e *Events) UnRegister(evName, sessionID string) error {
+       evs := xsapiv1.EVTAllList
+       if evName != xsapiv1.EVTAll {
+               if _, ok := e.eventsMap[evName]; !ok {
+                       return fmt.Errorf("Unsupported event type name")
+               }
+               evs = []string{evName}
+       }
+       for _, ev := range evs {
+               if _, exist := e.eventsMap[ev].sids[sessionID]; exist {
+                       delete(e.eventsMap[ev].sids, sessionID)
+                       break
+               }
+       }
+       return nil
+}
+
+// Emit Used to manually emit an event
+func (e *Events) Emit(evName string, data interface{}, fromSid string) error {
+       var firstErr error
+
+       if _, ok := e.eventsMap[evName]; !ok {
+               return fmt.Errorf("Unsupported event type")
+       }
+
+       firstErr = nil
+       evm := e.eventsMap[evName]
+       e.LogSillyf("Emit Event %s: len(sids)=%d, data=%v", evName, len(evm.sids), data)
+       for sid := range evm.sids {
+               so := e.sessions.IOSocketGet(sid)
+               if so == nil {
+                       if firstErr == nil {
+                               firstErr = fmt.Errorf("IOSocketGet return nil (SID=%v)", sid)
+                       }
+                       continue
+               }
+               msg := xsapiv1.EventMsg{
+                       Time:          time.Now().String(),
+                       FromSessionID: fromSid,
+                       Type:          evName,
+                       Data:          data,
+               }
+               e.Log.Debugf("Emit Event %s: %v", evName, sid)
+               if err := (*so).Emit(evName, msg); err != nil {
+                       e.Log.Errorf("WS Emit %v error : %v", evName, err)
+                       if firstErr == nil {
+                               firstErr = err
+                       }
+               }
+       }
+
+       return firstErr
+}