deploy: add healthcheck

unfortunately healthchecks do not work with scratch images since they do not have systemd, thats why switch runner image to alpine

cmd/healthcheck/main.go

@@ -0,0 +1,48 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+	"strings"
+
+	"github.com/go-playground/validator/v10"
+	"github.com/knadh/koanf/providers/env"
+	"github.com/knadh/koanf/v2"
+)
+
+type Config struct {
+	Addr string `koanf:"addr" validate:"required" json:"addr"`
+}
+
+func main() {
+	conf := Config{Addr: "localhost:8080"}
+
+	k := koanf.New(".")
+	k.Load(env.Provider("UNOTONE_", ".", func(s string) string {
+		s = strings.TrimPrefix(s, "UNOTONE_")
+		s = strings.ToLower(s)
+		return s
+	}), nil)
+	k.Unmarshal("", &conf)
+
+	validate := validator.New(validator.WithRequiredStructEnabled())
+
+	if err := validate.Struct(&conf); err != nil {
+		fmt.Printf("failed ot validate config: %v\n", err)
+		os.Exit(1)
+	}
+
+	resp, err := http.Get(fmt.Sprintf("http://%s/health", conf.Addr))
+	if err != nil {
+		fmt.Printf("failed to get healthcheck: %v\n", err)
+		os.Exit(1)
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		fmt.Errorf("health check failed with status code %d\n", resp.StatusCode)
+		os.Exit(1)
+	}
+
+	os.Exit(0)
+}

dockerfile

@@ -29,13 +29,17 @@ COPY cmd ./cmd
 COPY controllers ./controllers
 COPY --from=templbuilder /build/controllers/web/components/*_templ.go ./controllers/web/components/
 RUN go build -ldflags="-s -w" -o /app/unotone ./cmd/server/main.go
+RUN go build -ldflags="-s -w" -o /app/healthcheck ./cmd/healthcheck/main.go
 RUN chmod +x /app/unotone
 
 # runner image
-FROM scratch
+FROM alpine
 WORKDIR /app
 ENV UNOTONE_STATIC_DIR /var/www/static
+ENV PATH /app:$PATH
 COPY --from=gobuilder /build/controllers/web/static ${UNOTONE_STATIC_DIR}
 COPY --from=tailwindbuilder /build/static/output.css ${UNOTONE_STATIC_DIR}/output.css
 COPY --from=gobuilder /app/unotone /app/unotone
-CMD ["./unotone"]
+COPY --from=gobuilder /app/healthcheck /app/healthcheck
+HEALTHCHECK --start-period=1s --interval=1m --timeout=3s --retries=3 CMD ["healthcheck"]
+CMD ["unotone"]

justfile

@@ -22,6 +22,11 @@ run-pod: podman-build
         --restart unless-stopped \
         --name unotone-server \
         --detach \
+        --health-cmd 'healthcheck --port 8080' \
+        --health-start-period 1s \
+        --health-interval 1m \
+        --health-timeout 3s \
+        --health-retries 3 \
         -e UNOTONE_ADDR=0.0.0.0:8080 \
         -e UNOTONE_DEBUG={{ DEBUG }} \
         unotone-server:latest