Overall metrics health check

utils/overall-health-check/Dockerfile

@@ -0,0 +1,27 @@
+# Start from a base image with Go installed
+FROM golang:1.21-alpine as builder
+
+# Set the working directory inside the container
+WORKDIR /app
+
+# Copy the Go module
+COPY go.mod ./
+
+# Download Go module dependencies
+RUN go mod download
+
+# Copy the source code into the container
+COPY main.go ./
+
+# Compile the application
+RUN go build -o healthcheck
+
+#########################  RUNTIME ########################
+FROM scratch
+
+# Copy the Pre-built binary file from the previous stage
+COPY --from=builder /app/healthcheck .
+ENV PATH="/"
+
+# Run the executable
+CMD ["./healthcheck"]

utils/overall-health-check/go.mod

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+module healthcheck
+
+go 1.21

utils/overall-health-check/main.go

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+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"regexp"
+)
+
+func main() {
+	var metricsPort, apiPort int
+	flag.IntVar(&metricsPort, "metrics-port", 9090, "Port where Prometheus metrics are exposed")
+	flag.IntVar(&apiPort, "api-port", 8081, "Port to expose health check API")
+	flag.Parse()
+
+	http.HandleFunc("/overall_health", func(w http.ResponseWriter, r *http.Request) {
+		healthCheckHandler(w, r, metricsPort)
+	})
+
+	log.Printf("Checking health on port %d", metricsPort)
+	log.Printf("Starting health check API server on port %d", apiPort)
+	log.Fatal(http.ListenAndServe(fmt.Sprintf(":%d", apiPort), nil))
+}
+
+func healthCheckHandler(w http.ResponseWriter, r *http.Request, metricsPort int) {
+	resp, err := http.Get(fmt.Sprintf("http://localhost:%d/metrics", metricsPort))
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	re := regexp.MustCompile(`lava_consumer_overall_health (\d+)`)
+	matches := re.FindStringSubmatch(string(body))
+	if len(matches) > 1 && matches[1] == "1" {
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte("Healthy"))
+	} else {
+		http.Error(w, "Unhealthy", http.StatusServiceUnavailable)
+	}
+}