github.com/demonoid81/moby@v0.0.0-20200517203328-62dd8e17c460/container/health.go (about) 1 package container // import "github.com/demonoid81/moby/container" 2 3 import ( 4 "sync" 5 6 "github.com/demonoid81/moby/api/types" 7 "github.com/sirupsen/logrus" 8 ) 9 10 // Health holds the current container health-check state 11 type Health struct { 12 types.Health 13 stop chan struct{} // Write struct{} to stop the monitor 14 mu sync.Mutex 15 } 16 17 // String returns a human-readable description of the health-check state 18 func (s *Health) String() string { 19 status := s.Status() 20 21 switch status { 22 case types.Starting: 23 return "health: starting" 24 default: // Healthy and Unhealthy are clear on their own 25 return status 26 } 27 } 28 29 // Status returns the current health status. 30 // 31 // Note that this takes a lock and the value may change after being read. 32 func (s *Health) Status() string { 33 s.mu.Lock() 34 defer s.mu.Unlock() 35 36 // This happens when the monitor has yet to be setup. 37 if s.Health.Status == "" { 38 return types.Unhealthy 39 } 40 41 return s.Health.Status 42 } 43 44 // SetStatus writes the current status to the underlying health structure, 45 // obeying the locking semantics. 46 // 47 // Status may be set directly if another lock is used. 48 func (s *Health) SetStatus(new string) { 49 s.mu.Lock() 50 defer s.mu.Unlock() 51 52 s.Health.Status = new 53 } 54 55 // OpenMonitorChannel creates and returns a new monitor channel. If there 56 // already is one, it returns nil. 57 func (s *Health) OpenMonitorChannel() chan struct{} { 58 s.mu.Lock() 59 defer s.mu.Unlock() 60 61 if s.stop == nil { 62 logrus.Debug("OpenMonitorChannel") 63 s.stop = make(chan struct{}) 64 return s.stop 65 } 66 return nil 67 } 68 69 // CloseMonitorChannel closes any existing monitor channel. 70 func (s *Health) CloseMonitorChannel() { 71 s.mu.Lock() 72 defer s.mu.Unlock() 73 74 if s.stop != nil { 75 logrus.Debug("CloseMonitorChannel: waiting for probe to stop") 76 close(s.stop) 77 s.stop = nil 78 // unhealthy when the monitor has stopped for compatibility reasons 79 s.Health.Status = types.Unhealthy 80 logrus.Debug("CloseMonitorChannel done") 81 } 82 }