Merge pull request #631 from cj123/healthcheck-endpoint

add a health check endpoint

CHANGELOG.md

@@ -15,6 +15,7 @@ Added:
 * You can now filter stock, DLC and mod cars in or out of the car search. Check out the car search help for more details! Please note that you will need to rebuild your search index for this to work. Go to Server Options, scroll down to "Maintenance" and click "Rebuild Search Index"!
 * Server Manager will now set up some example Championships and Custom Races if you have not yet created any
 * You can now sort the EntryList for a Championship Race Weekend Session by the number of Championship points a driver has. This could be useful for running reverse grid qualifying races!
+* Added a health-check endpoint. Hopefully this will help us with debugging issues!
 
 Fixes:
 

healthcheck.go

@@ -0,0 +1,91 @@
+package servermanager
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path/filepath"
+	"runtime"
+	"time"
+
+	"github.com/cj123/assetto-server-manager/pkg/udp"
+)
+
+var LaunchTime = time.Now()
+
+type HealthCheck struct {
+	raceControl *RaceControl
+}
+
+func NewHealthCheck(raceControl *RaceControl) *HealthCheck {
+	return &HealthCheck{raceControl: raceControl}
+}
+
+type HealthCheckResponse struct {
+	OK        bool
+	Version   string
+	IsPremium bool
+	IsHosted  bool
+
+	OS            string
+	NumCPU        int
+	NumGoroutines int
+	Uptime        string
+	GoVersion     string
+
+	AssettoIsInstalled  bool
+	StrackerIsInstalled bool
+
+	CarDirectoryIsWritable     bool
+	TrackDirectoryIsWritable   bool
+	WeatherDirectoryIsWritable bool
+	SetupsDirectoryIsWritable  bool
+	ConfigDirectoryIsWritable  bool
+	ResultsDirectoryIsWritable bool
+
+	EventInProgress     bool
+	EventIsCritical     bool
+	NumConnectedDrivers int
+	MaxClientsOverride  int
+}
+
+func (h *HealthCheck) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	event := h.raceControl.process.Event()
+
+	_ = json.NewEncoder(w).Encode(HealthCheckResponse{
+		OK:                 true,
+		OS:                 runtime.GOOS + "/" + runtime.GOARCH,
+		Version:            BuildVersion,
+		IsPremium:          IsPremium == "true",
+		IsHosted:           IsHosted,
+		MaxClientsOverride: MaxClientsOverride,
+		NumCPU:             runtime.NumCPU(),
+		NumGoroutines:      runtime.NumGoroutine(),
+		Uptime:             time.Since(LaunchTime).String(),
+		GoVersion:          runtime.Version(),
+
+		EventInProgress:     h.raceControl.process.IsRunning(),
+		EventIsCritical:     !event.IsPractice() && (event.IsChampionship() || event.IsRaceWeekend() || h.raceControl.SessionInfo.Type == udp.SessionTypeRace || h.raceControl.SessionInfo.Type == udp.SessionTypeQualifying),
+		NumConnectedDrivers: h.raceControl.ConnectedDrivers.Len(),
+		AssettoIsInstalled:  IsAssettoInstalled(),
+		StrackerIsInstalled: IsStrackerInstalled(),
+
+		ConfigDirectoryIsWritable:  IsDirWriteable(filepath.Join(ServerInstallPath, "cfg")) == nil,
+		CarDirectoryIsWritable:     IsDirWriteable(filepath.Join(ServerInstallPath, "content", "cars")) == nil,
+		TrackDirectoryIsWritable:   IsDirWriteable(filepath.Join(ServerInstallPath, "content", "tracks")) == nil,
+		WeatherDirectoryIsWritable: IsDirWriteable(filepath.Join(ServerInstallPath, "content", "weather")) == nil,
+		SetupsDirectoryIsWritable:  IsDirWriteable(filepath.Join(ServerInstallPath, "setups")) == nil,
+		ResultsDirectoryIsWritable: IsDirWriteable(filepath.Join(ServerInstallPath, "results")) == nil,
+	})
+}
+
+func IsDirWriteable(dir string) error {
+	file := filepath.Join(dir, ".test-write")
+
+	if err := ioutil.WriteFile(file, []byte(""), 0600); err != nil {
+		return err
+	}
+
+	return os.Remove(file)
+}

resolver.go

@@ -45,6 +45,7 @@ type Resolver struct {
 	serverAdministrationHandler *ServerAdministrationHandler
 	raceWeekendHandler          *RaceWeekendHandler
 	strackerHandler             *StrackerHandler
+	healthCheck                 *HealthCheck
 }
 
 func NewResolver(templateLoader TemplateLoader, reloadTemplates bool, store Store) (*Resolver, error) {
@@ -426,6 +427,16 @@ func (r *Resolver) resolveStrackerHandler() *StrackerHandler {
 	return r.strackerHandler
 }
 
+func (r *Resolver) resolveHealthCheck() *HealthCheck {
+	if r.healthCheck != nil {
+		return r.healthCheck
+	}
+
+	r.healthCheck = NewHealthCheck(r.resolveRaceControl())
+
+	return r.healthCheck
+}
+
 func (r *Resolver) ResolveRouter(fs http.FileSystem) http.Handler {
 	return Router(
 		fs,
@@ -445,6 +456,7 @@ func (r *Resolver) ResolveRouter(fs http.FileSystem) http.Handler {
 		r.resolveScheduledRacesHandler(),
 		r.resolveRaceWeekendHandler(),
 		r.resolveStrackerHandler(),
+		r.resolveHealthCheck(),
 	)
 }
 

router.go

@@ -61,6 +61,7 @@ func Router(
 	scheduledRacesHandler *ScheduledRacesHandler,
 	raceWeekendHandler *RaceWeekendHandler,
 	strackerHandler *StrackerHandler,
+	healthCheck *HealthCheck,
 ) http.Handler {
 	r := chi.NewRouter()
 
@@ -86,6 +87,8 @@ func Router(
 		r.Get("/", serverAdministrationHandler.home)
 		r.Get("/changelog", serverAdministrationHandler.changelog)
 
+		r.Get("/healthcheck.json", healthCheck.ServeHTTP)
+
 		r.Mount("/stracker/", http.HandlerFunc(strackerHandler.proxy))
 
 		// content

server_install.go

@@ -36,6 +36,16 @@ func SetAssettoInstallPath(installPath string) {
 	}
 }
 
+func IsAssettoInstalled() bool {
+	_, err := os.Stat(filepath.Join(ServerInstallPath, "system"))
+
+	if err != nil {
+		return false
+	}
+
+	return true
+}
+
 // InstallAssettoCorsaServer takes a steam login and password and runs steamcmd to install the assetto server.
 // If the "ServerInstallPath" exists, this function will exit without installing - unless force == true.
 func InstallAssettoCorsaServer(login, password string, force bool) error {