// Send the KeepAlive message to server in order to inform server the discovery is stil ongoing. Prevent timeout.
func (this *ExampleServerMessageHandler) keepDiscoveryAlive(msgID int32) {
glog.V(3).Infof("Keep Alive is called for message with ID: %d", msgID)
keepAliveMsg := new(proto.KeepAlive)
clientMsg := comm.NewClientMessageBuilder(msgID).SetKeepAlive(keepAliveMsg).Create()
this.clientMsgChan <- clientMsg
}
// Implement comm.ServerMessageHandler Interface -> DiscoverTopology()
func (this *ExampleServerMessageHandler) DiscoverTopology(serverMsg *proto.MediationServerMessage) {
glog.V(2).Infof("Now discovering toplogy of target %s.", this.TurboMetadata.NameOrAddress)
// 1. Get message ID.
msgID := serverMsg.GetMessageID()
// 2. Stop being timed out. Send back KeepAlive message every 10s.
stopCh := make(chan struct{})
defer close(stopCh)
go func() {
for {
select {
case <-stopCh:
return
default:
}
this.keepDiscoveryAlive(msgID)
t := time.NewTimer(time.Second * 10)
select {
case <-stopCh:
return
case <-t.C:
}
}
}()
// 3. Create probe and use probe to discover target topology.
exampleProbe := probe.NewExampleProbe(this.TopoAccessor)
discoveryResults, err := exampleProbe.Discover()
// 4. Build discovery response.
// If there is error during discovery, return an ErrorDTO.
var discoveryResponse *proto.DiscoveryResponse
if err != nil {
// If there is error during discovery, return an ErrorDTO.
serverity := proto.ErrorDTO_CRITICAL
description := fmt.Sprintf("%v", err)
errorDTO := &proto.ErrorDTO{
Severity: &serverity,
Description: &description,
}
discoveryResponse = &proto.DiscoveryResponse{
ErrorDTO: []*proto.ErrorDTO{errorDTO},
}
} else {
// No error. Return the result entityDTOs.
discoveryResponse = &proto.DiscoveryResponse{
EntityDTO: discoveryResults,
}
}
// 5. Build client message.
clientMsg := comm.NewClientMessageBuilder(msgID).SetDiscoveryResponse(discoveryResponse).Create()
// 6. Send to client msg channel.
this.clientMsgChan <- clientMsg
}
// Implement comm.ServerMessageHandler Interface -> Validate()
func (this *ExampleServerMessageHandler) Validate(serverMsg *proto.MediationServerMessage) {
glog.V(2).Infof("Now validating target %s", this.TurboMetadata.NameOrAddress)
// NOTE: Here we validate regardless of what info sent along with Validation request from server.
// 1. Retreive message ID from server message.
msgID := serverMsg.GetMessageID()
// 2. Build validation response.
validationResponse := new(proto.ValidationResponse)
// 3. Create client message.
clientMsg := comm.NewClientMessageBuilder(msgID).SetValidationResponse(validationResponse).Create()
//4. Send it to client msg channel.
this.clientMsgChan <- clientMsg
}
