1 files changed, 108 insertions, 0 deletions
diff --git a/pkg/worker/state.go b/pkg/worker/state.go
new file mode 100755
index 00000000..176e151b
--- /dev/null
+++ b/pkg/worker/state.go
@@ -0,0 +1,108 @@
+package worker
+
+import (
+	"sync/atomic"
+)
+
+// SYNC WITH worker_watcher.GET
+const (
+	// StateInactive - no associated process
+	StateInactive int64 = iota
+
+	// StateReady - ready for job.
+	StateReady
+
+	// StateWorking - working on given payload.
+	StateWorking
+
+	// StateInvalid - indicates that WorkerProcess is being disabled and will be removed.
+	StateInvalid
+
+	// StateStopping - process is being softly stopped.
+	StateStopping
+
+	// StateKilling - process is being forcibly stopped
+	StateKilling
+
+	// State of worker, when no need to allocate new one
+	StateDestroyed
+
+	// StateStopped - process has been terminated.
+	StateStopped
+
+	// StateErrored - error StateImpl (can't be used).
+	StateErrored
+)
+
+type StateImpl struct {
+	value    int64
+	numExecs uint64
+	// to be lightweight, use UnixNano
+	lastUsed uint64
+}
+
+// Thread safe
+func NewWorkerState(value int64) *StateImpl {
+	return &StateImpl{value: value}
+}
+
+// String returns current StateImpl as string.
+func (s *StateImpl) String() string {
+	switch s.Value() {
+	case StateInactive:
+		return "inactive"
+	case StateReady:
+		return "ready"
+	case StateWorking:
+		return "working"
+	case StateInvalid:
+		return "invalid"
+	case StateStopping:
+		return "stopping"
+	case StateStopped:
+		return "stopped"
+	case StateKilling:
+		return "killing"
+	case StateErrored:
+		return "errored"
+	case StateDestroyed:
+		return "destroyed"
+	}
+
+	return "undefined"
+}
+
+// NumExecs returns number of registered WorkerProcess execs.
+func (s *StateImpl) NumExecs() uint64 {
+	return atomic.LoadUint64(&s.numExecs)
+}
+
+// Value StateImpl returns StateImpl value
+func (s *StateImpl) Value() int64 {
+	return atomic.LoadInt64(&s.value)
+}
+
+// IsActive returns true if WorkerProcess not Inactive or Stopped
+func (s *StateImpl) IsActive() bool {
+	val := s.Value()
+	return val == StateWorking || val == StateReady
+}
+
+// change StateImpl value (status)
+func (s *StateImpl) Set(value int64) {
+	atomic.StoreInt64(&s.value, value)
+}
+
+// register new execution atomically
+func (s *StateImpl) RegisterExec() {
+	atomic.AddUint64(&s.numExecs, 1)
+}
+
+// Update last used time
+func (s *StateImpl) SetLastUsed(lu uint64) {
+	atomic.StoreUint64(&s.lastUsed, lu)
+}
+
+func (s *StateImpl) LastUsed() uint64 {
+	return atomic.LoadUint64(&s.lastUsed)
+}