feat: add healthcheck

flake.nix

@@ -53,7 +53,18 @@
               name = "image-root";
               paths = [packages.app];
             };
-            config.Cmd = ["app"];
+            config = let
+              healthcheck = pkgs.writeShellApplication {
+                name = "healthcheck";
+                runtimeInputs = [pkgs.curl];
+                text = ''
+                  test "$(curl --fail localhost:8080/health)" = "OK"
+                '';
+              };
+            in {
+              Healthcheck.Test = ["CMD" "${pkgs.lib.getExe healthcheck}"];
+              Entrypoint = ["app"];
+            };
           };
         };
 

main.go

@@ -4,6 +4,7 @@ import (
 	"app/pkg/app"
 	"app/pkg/routes/blog"
 	"app/pkg/routes/contact"
+	"app/pkg/routes/health"
 	"app/pkg/routes/resume"
 	"app/pkg/routes/root"
 )
@@ -12,6 +13,7 @@ func main() {
 	serv := app.Server{Port: 8080}
 
 	serv.AddRoute("GET /", root.Handler)
+	serv.AddRoute("GET /health", health.Handler)
 	serv.AddRoute("GET /blog/{article...}", blog.Handler)
 	serv.AddRoute("GET /contact", contact.Handler)
 	serv.AddRoute("GET /resume", resume.Handler)

pkg/routes/health/health.go

@@ -0,0 +1,15 @@
+package health
+
+import (
+	"io"
+	"net/http"
+
+	"app/pkg/app"
+
+	"github.com/a-h/templ"
+)
+
+func Handler(serv *app.Server, w http.ResponseWriter, r *http.Request) (templ.Component, error) {
+	io.WriteString(w, "OK")
+	return nil, nil
+}