Add monitor/debug packages

monitor/monitor.go

@@ -0,0 +1,39 @@
+// Package monitor monitors service health
+package monitor
+
+import (
+	"errors"
+)
+
+const (
+	StatusUnknown StatusCode = iota
+	StatusRunning
+	StatusFailed
+)
+
+type StatusCode int
+
+// Monitor monitors a service and reaps dead instances
+type Monitor interface {
+	// Status of the service
+	Status(service string) (Status, error)
+	// Watch starts watching the service
+	Watch(service string) error
+	// Stop monitoring
+	Stop() error
+}
+
+type Status struct {
+	Code  StatusCode
+	Info  string
+	Error string
+}
+
+var (
+	ErrNotWatching = errors.New("not watching")
+)
+
+// NewMonitor returns a new monitor
+func NewMonitor(opts ...Option) Monitor {
+	return newMonitor(opts...)
+}