add health endpoint

controller/health.go

@@ -0,0 +1,21 @@
+package controller
+
+import (
+	"net/http"
+
+	"github.com/tarkov-database/rest-api/model/api"
+	"github.com/tarkov-database/rest-api/view"
+
+	"github.com/julienschmidt/httprouter"
+)
+
+// HealthGET handles a GET request on the health endpoint
+func HealthGET(w http.ResponseWriter, _ *http.Request, _ httprouter.Params) {
+	h, err := api.GetHealth()
+
+	if err != nil || !h.OK {
+		view.RenderJSON(h, http.StatusInternalServerError, w)
+	} else {
+		view.RenderJSON(h, http.StatusOK, w)
+	}
+}

core/database/database.go

@@ -7,7 +7,6 @@ import (
 
 	"github.com/google/logger"
 	"go.mongodb.org/mongo-driver/mongo"
-	"go.mongodb.org/mongo-driver/mongo/readpref"
 )
 
 var db *mongo.Database
@@ -36,7 +35,7 @@ func Init() error {
 	ctx, cancel = context.WithTimeout(context.Background(), 5*time.Second)
 	defer cancel()
 
-	if err := client.Ping(ctx, readpref.Primary()); err != nil {
+	if err := client.Ping(ctx, nil); err != nil {
 		return fmt.Errorf("connection error: %s", err)
 	}
 
@@ -63,6 +62,17 @@ func Shutdown() error {
 	return nil
 }
 
+// Ping sends a ping command to verify the DB connection
+func Ping(ctx context.Context) error {
+	client := db.Client()
+
+	if err := client.Ping(ctx, nil); err != nil {
+		return fmt.Errorf("connection error: %s", err)
+	}
+
+	return nil
+}
+
 // GetDB returns a handle to the database
 func GetDB() *mongo.Database {
 	return db

model/api/health.go

@@ -0,0 +1,74 @@
+package api
+
+import (
+	"context"
+	"time"
+
+	"github.com/tarkov-database/rest-api/core/database"
+)
+
+// Status represents the status code of a service
+type Status int
+
+const (
+	// OK status if all checks were successful
+	OK Status = iota
+
+	// Warning status if non-critical issues are discovered
+	Warning
+
+	// Failure status when critical problems are discovered
+	Failure
+)
+
+// Health represents the object of the health root endpoint
+type Health struct {
+	OK      bool     `json:"ok"`
+	Service *Service `json:"service"`
+}
+
+// Service holds all services with their respective status
+type Service struct {
+	Database Status `json:"database"`
+}
+
+// GetHealth performs a self-check and returns the result
+func GetHealth() (*Health, error) {
+	var err error
+	var ok = true
+
+	svc := &Service{}
+
+	svc.Database, err = getDatabaseStatus()
+	if err != nil {
+		return nil, err
+	}
+
+	if svc.Database != OK {
+		ok = false
+	}
+
+	health := &Health{
+		OK:      ok,
+		Service: svc,
+	}
+
+	return health, nil
+}
+
+func getDatabaseStatus() (Status, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+
+	start := time.Now()
+
+	if err := database.Ping(ctx); err != nil {
+		return Failure, err
+	}
+
+	if time.Since(start).Seconds() > 3 {
+		return Warning, nil
+	}
+
+	return OK, nil
+}

route/route.go

@@ -23,6 +23,9 @@ func routes() *httprouter.Router {
 	r.GET(prefix, cntrl.IndexGET)
 	r.Handler("GET", "/", http.RedirectHandler(prefix, http.StatusMovedPermanently))
 
+	// Health
+	r.GET(prefix+"/health", cntrl.HealthGET)
+
 	// Item
 	r.GET(prefix+"/item", auth(jwt.ScopeItemRead, cntrl.ItemIndexGET))
 	r.GET(prefix+"/item/:kind", auth(jwt.ScopeItemRead, cntrl.ItemsGET))