fix(lifecycle): cleanup lifecycle

- removes unwieldy SkipUpdate return value in favor of errors.Is
- generalizes the code for all four phases
- allows timeout to be defined for all phases
- enables explicit unit in timeout label values (in addition to implicit minutes)

pkg/types/container.go

@@ -2,6 +2,7 @@ package types
 
 import (
 	"strings"
+	"time"
 
 	"github.com/docker/docker/api/types"
 	dc "github.com/docker/docker/api/types/container"
@@ -60,18 +61,14 @@ type Container interface {
 	StopSignal() string
 	HasImageInfo() bool
 	ImageInfo() *types.ImageInspect
-	GetLifecyclePreCheckCommand() string
-	GetLifecyclePostCheckCommand() string
-	GetLifecyclePreUpdateCommand() string
-	GetLifecyclePostUpdateCommand() string
+	GetLifecycleCommand(LifecyclePhase) string
+	GetLifecycleTimeout(LifecyclePhase) time.Duration
 	VerifyConfiguration() error
 	SetStale(bool)
 	IsStale() bool
 	IsNoPull(UpdateParams) bool
 	SetLinkedToRestarting(bool)
 	IsLinkedToRestarting() bool
-	PreUpdateTimeout() int
-	PostUpdateTimeout() int
 	IsRestarting() bool
 	GetCreateConfig() *dc.Config
 	GetCreateHostConfig() *dc.HostConfig

pkg/types/lifecycle.go

@@ -0,0 +1,27 @@
+package types
+
+import "fmt"
+
+type LifecyclePhase int
+
+const (
+	PreCheck LifecyclePhase = iota
+	PreUpdate
+	PostUpdate
+	PostCheck
+)
+
+func (p LifecyclePhase) String() string {
+	switch p {
+	case PreCheck:
+		return "pre-check"
+	case PreUpdate:
+		return "pre-update"
+	case PostUpdate:
+		return "post-update"
+	case PostCheck:
+		return "post-check"
+	default:
+		return fmt.Sprintf("invalid(%d)", p)
+	}
+}