Add RescheduleTracker to allocations API struct

api/allocations.go

@@ -97,6 +97,7 @@ type Allocation struct {
 	AllocModifyIndex   uint64
 	CreateTime         int64
 	ModifyTime         int64
+	RescheduleTracker  *RescheduleTracker
 }
 
 // AllocationMetric is used to deserialize allocation metrics.
@@ -135,6 +136,7 @@ type AllocationListStub struct {
 	ModifyIndex        uint64
 	CreateTime         int64
 	ModifyTime         int64
+	RescheduleTracker  *RescheduleTracker
 }
 
 // AllocDeploymentStatus captures the status of the allocation as part of the
@@ -159,3 +161,20 @@ func (a AllocIndexSort) Less(i, j int) bool {
 func (a AllocIndexSort) Swap(i, j int) {
 	a[i], a[j] = a[j], a[i]
 }
+
+// RescheduleTracker encapsulates previous reschedule events
+type RescheduleTracker struct {
+	Events []*RescheduleEvent
+}
+
+// RescheduleEvent is used to keep track of previous attempts at rescheduling an allocation
+type RescheduleEvent struct {
+	// RescheduleTime is the timestamp of a reschedule attempt
+	RescheduleTime int64
+
+	// PrevAllocID is the ID of the previous allocation being restarted
+	PrevAllocID string
+
+	// PrevNodeID is the node ID of the previous allocation
+	PrevNodeID string
+}

nomad/alloc_endpoint_test.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/hashicorp/net-rpc-msgpackrpc"
 	"github.com/hashicorp/nomad/acl"
+	"github.com/hashicorp/nomad/helper/uuid"
 	"github.com/hashicorp/nomad/nomad/mock"
 	"github.com/hashicorp/nomad/nomad/structs"
 	"github.com/hashicorp/nomad/testutil"
@@ -218,7 +219,13 @@ func TestAllocEndpoint_GetAlloc(t *testing.T) {
 	testutil.WaitForLeader(t, s1.RPC)
 
 	// Create the register request
+	prevAllocID := uuid.Generate()
 	alloc := mock.Alloc()
+	alloc.RescheduleTracker = &structs.RescheduleTracker{
+		Events: []*structs.RescheduleEvent{
+			{RescheduleTime: time.Now().UTC().UnixNano(), PrevNodeID: "boom", PrevAllocID: prevAllocID},
+		},
+	}
 	state := s1.fsm.State()
 	state.UpsertJobSummary(999, mock.JobSummary(alloc.JobID))
 	err := state.UpsertAllocs(1000, []*structs.Allocation{alloc})