Add updating cached allocations

runner/manager.go

@@ -1,9 +1,12 @@
 package runner
 
 import (
+	"context"
 	"errors"
+	nomadApi "github.com/hashicorp/nomad/api"
 	"gitlab.hpi.de/codeocean/codemoon/poseidon/logging"
 	"gitlab.hpi.de/codeocean/codemoon/poseidon/nomad"
+	"strconv"
 	"time"
 )
 
@@ -49,12 +52,14 @@ type NomadRunnerManager struct {
 	usedRunners Storage
 }
 
-func NewNomadRunnerManager(apiClient nomad.ExecutorApi) *NomadRunnerManager {
-	return &NomadRunnerManager{
+func NewNomadRunnerManager(apiClient nomad.ExecutorApi, ctx context.Context) *NomadRunnerManager {
+	m := &NomadRunnerManager{
 		apiClient,
 		NewLocalNomadJobStorage(),
 		NewLocalRunnerStorage(),
 	}
+	go m.updateRunners(ctx)
+	return m
 }
 
 type NomadJob struct {
@@ -113,6 +118,41 @@ func (m *NomadRunnerManager) Return(r Runner) (err error) {
 	return
 }
 
+func (m *NomadRunnerManager) updateRunners(ctx context.Context) {
+	onCreate := func(alloc *nomadApi.Allocation) {
+		log.WithField("id", alloc.ID).Debug("Allocation started")
+
+		intJobID, err := strconv.Atoi(alloc.JobID)
+		if err != nil {
+			return
+		}
+
+		job, ok := m.jobs.Get(EnvironmentId(intJobID))
+		if ok {
+			job.idleRunners.Add(NewRunner(alloc.ID))
+		}
+	}
+	onStop := func(alloc *nomadApi.Allocation) {
+		log.WithField("id", alloc.ID).Debug("Allocation stopped")
+
+		intJobID, err := strconv.Atoi(alloc.JobID)
+		if err != nil {
+			return
+		}
+
+		job, ok := m.jobs.Get(EnvironmentId(intJobID))
+		if ok {
+			job.idleRunners.Delete(alloc.ID)
+			m.usedRunners.Delete(alloc.ID)
+		}
+	}
+
+	err := m.apiClient.WatchAllocations(ctx, onCreate, onStop)
+	if err != nil {
+		log.WithError(err).Error("Failed updating runners")
+	}
+}
+
 // Refresh Big ToDo: Improve this function!! State out that it also rescales the job; Provide context to be terminable...
 func (m *NomadRunnerManager) refreshEnvironment(id EnvironmentId) {
 	job, ok := m.jobs.Get(id)