Add statistics route for execution environments

* Add statistics route for execution environments

* Add maximum to port api definition

Co-authored-by: Sebastian Serth <MrSerth@users.noreply.github.com>

internal/api/api.go

@@ -6,6 +6,7 @@ import (
 	"github.com/openHPI/poseidon/internal/config"
 	"github.com/openHPI/poseidon/internal/environment"
 	"github.com/openHPI/poseidon/internal/runner"
+	"github.com/openHPI/poseidon/pkg/dto"
 	"github.com/openHPI/poseidon/pkg/logging"
 	"net/http"
 )
@@ -18,6 +19,7 @@ const (
 	VersionPath      = "/version"
 	RunnersPath      = "/runners"
 	EnvironmentsPath = "/execution-environments"
+	StatisticsPath   = "/statistics"
 )
 
 // NewRouter returns a *mux.Router which can be
@@ -46,10 +48,14 @@ func configureV1Router(router *mux.Router, runnerManager runner.Manager, environ
 
 	runnerController := &RunnerController{manager: runnerManager}
 	environmentController := &EnvironmentController{manager: environmentManager}
-
 	configureRoutes := func(router *mux.Router) {
 		runnerController.ConfigureRoutes(router)
 		environmentController.ConfigureRoutes(router)
+
+		// May add a statistics controller if another route joins
+		statisticsRouter := router.PathPrefix(StatisticsPath).Subrouter()
+		statisticsRouter.
+			HandleFunc(EnvironmentsPath, StatisticsExecutionEnvironments(environmentManager)).Methods(http.MethodGet)
 	}
 
 	if auth.InitializeAuthentication() {
@@ -73,3 +79,16 @@ func Version(writer http.ResponseWriter, _ *http.Request) {
 		writer.WriteHeader(http.StatusNotFound)
 	}
 }
+
+// StatisticsExecutionEnvironments handles the route for statistics about execution environments.
+// It responds the prewarming pool size and the number of idle runners and used runners.
+func StatisticsExecutionEnvironments(manager environment.Manager) http.HandlerFunc {
+	return func(writer http.ResponseWriter, _ *http.Request) {
+		result := make(map[string]*dto.StatisticalExecutionEnvironmentData)
+		environmentsData := manager.Statistics()
+		for id, data := range environmentsData {
+			result[id.ToString()] = data
+		}
+		sendJSON(writer, result, http.StatusOK)
+	}
+}

internal/environment/environment.go

@@ -254,6 +254,10 @@ func (n *NomadEnvironment) DeleteRunner(id string) {
 	n.idleRunners.Delete(id)
 }
 
+func (n *NomadEnvironment) IdleRunnerCount() int {
+	return n.idleRunners.Length()
+}
+
 // MarshalJSON implements the json.Marshaler interface.
 // This converts the NomadEnvironment into the expected schema for dto.ExecutionEnvironmentData.
 func (n *NomadEnvironment) MarshalJSON() (res []byte, err error) {

internal/environment/manager.go

@@ -44,6 +44,9 @@ type Manager interface {
 	// Delete removes the specified execution environment.
 	// Iff the specified environment could not be found Delete returns false.
 	Delete(id dto.EnvironmentID) (bool, error)
+
+	// Statistics returns statistical data for each execution environment.
+	Statistics() map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData
 }
 
 type NomadEnvironmentManager struct {
@@ -156,6 +159,10 @@ func (m *NomadEnvironmentManager) Delete(id dto.EnvironmentID) (bool, error) {
 	return true, nil
 }
 
+func (m *NomadEnvironmentManager) Statistics() map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData {
+	return m.runnerManager.EnvironmentStatistics()
+}
+
 func (m *NomadEnvironmentManager) Load() error {
 	templateJobs, err := m.api.LoadEnvironmentJobs()
 	if err != nil {

internal/environment/manager_mock.go

@@ -115,3 +115,19 @@ func (_m *ManagerMock) Load() error {
 
 	return r0
 }
+
+// Statistics provides a mock function with given fields:
+func (_m *ManagerMock) Statistics() map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData {
+	ret := _m.Called()
+
+	var r0 map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData
+	if rf, ok := ret.Get(0).(func() map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData); ok {
+		r0 = rf()
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData)
+		}
+	}
+
+	return r0
+}

internal/runner/execution_environment_mock.go

@@ -66,6 +66,20 @@ func (_m *ExecutionEnvironmentMock) ID() dto.EnvironmentID {
 	return r0
 }
 
+// IdleRunnerCount provides a mock function with given fields:
+func (_m *ExecutionEnvironmentMock) IdleRunnerCount() int {
+	ret := _m.Called()
+
+	var r0 int
+	if rf, ok := ret.Get(0).(func() int); ok {
+		r0 = rf()
+	} else {
+		r0 = ret.Get(0).(int)
+	}
+
+	return r0
+}
+
 // Image provides a mock function with given fields:
 func (_m *ExecutionEnvironmentMock) Image() string {
 	ret := _m.Called()

internal/runner/manager.go

@@ -62,6 +62,8 @@ type ExecutionEnvironment interface {
 	AddRunner(r Runner)
 	// DeleteRunner removes an idle runner from the environment.
 	DeleteRunner(id string)
+	// IdleRunnerCount returns the number of idle runners of the environment.
+	IdleRunnerCount() int
 }
 
 // Manager keeps track of the used and unused runners of all execution environments in order to provide unused
@@ -82,6 +84,9 @@ type Manager interface {
 	// It does nothing if the specified environment can not be found.
 	DeleteEnvironment(id dto.EnvironmentID)
 
+	// EnvironmentStatistics returns statistical data for each execution environment.
+	EnvironmentStatistics() map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData
+
 	// Claim returns a new runner. The runner is deleted after duration seconds if duration is not 0.
 	// It makes sure that the runner is not in use yet and returns an error if no runner could be provided.
 	Claim(id dto.EnvironmentID, duration int) (Runner, error)
@@ -136,6 +141,27 @@ func (m *NomadRunnerManager) DeleteEnvironment(id dto.EnvironmentID) {
 	m.environments.Delete(id)
 }
 
+func (m *NomadRunnerManager) EnvironmentStatistics() map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData {
+	environments := make(map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData)
+	for _, e := range m.environments.List() {
+		environments[e.ID()] = &dto.StatisticalExecutionEnvironmentData{
+			ID:                 int(e.ID()),
+			PrewarmingPoolSize: e.PrewarmingPoolSize(),
+			IdleRunners:        uint(e.IdleRunnerCount()),
+			UsedRunners:        0,
+		}
+	}
+
+	for _, r := range m.usedRunners.List() {
+		id, err := nomad.EnvironmentIDFromRunnerID(r.ID())
+		if err != nil {
+			log.WithError(err).Error("Stored runners must have correct IDs")
+		}
+		environments[id].UsedRunners++
+	}
+	return environments
+}
+
 func (m *NomadRunnerManager) Claim(environmentID dto.EnvironmentID, duration int) (Runner, error) {
 	environment, ok := m.environments.Get(environmentID)
 	if !ok {

internal/runner/manager_mock.go

@@ -40,6 +40,22 @@ func (_m *ManagerMock) DeleteEnvironment(id dto.EnvironmentID) {
 	_m.Called(id)
 }
 
+// EnvironmentStatistics provides a mock function with given fields:
+func (_m *ManagerMock) EnvironmentStatistics() map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData {
+	ret := _m.Called()
+
+	var r0 map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData
+	if rf, ok := ret.Get(0).(func() map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData); ok {
+		r0 = rf()
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(map[dto.EnvironmentID]*dto.StatisticalExecutionEnvironmentData)
+		}
+	}
+
+	return r0
+}
+
 // Get provides a mock function with given fields: runnerID
 func (_m *ManagerMock) Get(runnerID string) (Runner, error) {
 	ret := _m.Called(runnerID)

internal/runner/storage.go

@@ -6,6 +6,9 @@ import (
 
 // Storage is an interface for storing runners.
 type Storage interface {
+	// List returns all runners from the storage.
+	List() []Runner
+
 	// Add adds a runner to the storage.
 	// It overwrites the old runner if one with the same id was already stored.
 	Add(Runner)
@@ -41,6 +44,15 @@ func NewLocalRunnerStorage() *localRunnerStorage {
 	}
 }
 
+func (s *localRunnerStorage) List() (r []Runner) {
+	s.RLock()
+	defer s.RUnlock()
+	for _, value := range s.runners {
+		r = append(r, value)
+	}
+	return r
+}
+
 func (s *localRunnerStorage) Add(r Runner) {
 	s.Lock()
 	defer s.Unlock()