1 files changed, 88 insertions, 0 deletions
diff --git a/service/health/service.go b/service/health/service.go
new file mode 100644
index 00000000..c0be68e0
--- /dev/null
+++ b/service/health/service.go
@@ -0,0 +1,88 @@
+package health
+
+import (
+	"context"
+	"net/http"
+	"sync"
+
+	rrhttp "github.com/spiral/roadrunner/service/http"
+)
+
+// ID declares the public service name
+const ID = "health"
+
+// Service to serve an endpoint for checking the health of the worker pool
+type Service struct {
+	cfg         *Config
+	mu          sync.Mutex
+	http        *http.Server
+	httpService *rrhttp.Service
+}
+
+// Init health service
+func (s *Service) Init(cfg *Config, r *rrhttp.Service) (bool, error) {
+	// Ensure the httpService is set
+	if r == nil {
+		return false, nil
+	}
+
+	s.cfg = cfg
+	s.httpService = r
+	return true, nil
+}
+
+// Serve the health endpoint
+func (s *Service) Serve() error {
+	// Configure and start the http server
+	s.mu.Lock()
+	s.http = &http.Server{Addr: s.cfg.Address, Handler: s}
+	s.mu.Unlock()
+	return s.http.ListenAndServe()
+}
+
+// Stop the health endpoint
+func (s *Service) Stop() {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	if s.http != nil {
+		// gracefully stop the server
+		go s.http.Shutdown(context.Background())
+	}
+}
+
+// ServeHTTP returns the health of the pool of workers
+func (s *Service) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	status := http.StatusOK
+	if !s.isHealthy() {
+		status = http.StatusInternalServerError
+	}
+	w.WriteHeader(status)
+}
+
+// isHealthy checks the server, pool and ensures at least one worker is active
+func (s *Service) isHealthy() bool {
+	httpService := s.httpService
+	if httpService == nil {
+		return false
+	}
+
+	server := httpService.Server()
+	if server == nil {
+		return false
+	}
+
+	pool := server.Pool()
+	if pool == nil {
+		return false
+	}
+
+	// Ensure at least one worker is active
+	for _, w := range pool.Workers() {
+		if w.State().IsActive() {
+			return true
+		}
+	}
+
+	return false
+}