[core] Extend role with GetTaskPID

Author: miltalex

core/workflow/iteratorrole.go

@@ -271,3 +271,11 @@ func (i *iteratorRole) SetRuntimeVars(kv map[string]string) {
 	}
 	i.template.SetRuntimeVars(kv)
 }
+
+func (i *iteratorRole) GetTaskPID() string {
+	if i == nil {
+		return ""
+	}
+	pid, _ := i.template.GetUserVars().Get("taskPID")
+	return pid
+}

core/workflow/role.go

@@ -57,6 +57,7 @@ type Role interface {
 	GlobFilter(g glob.Glob) []Role
 	SetRuntimeVar(key string, value string)
 	SetRuntimeVars(kv map[string]string)
+	GetTaskPID() string
 }
 
 type Updatable interface {

core/workflow/rolebase.go

@@ -350,4 +350,12 @@ func (r *roleBase) CollectInboundChannels() (channels []channel.Inbound) {
 		channels = channel.MergeInbound(r.Bind, r.parent.CollectInboundChannels())
 	}	
 	return
+}
+
+func (r *roleBase) GetTaskPID() string {
+	if r == nil {
+		return ""
+	}
+	pid, _ := r.UserVars.Get("taskPID")
+	return pid
 }