first commit

q1-deploy-monitor/app/.dockerignore

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+.git
+.gitignore
+.env
+.env.*
+README.md
+Dockerfile
+.dockerignore
+dashboard

q1-deploy-monitor/app/Dockerfile

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+# Build stage
+FROM golang:1.26-alpine AS builder
+
+WORKDIR /app
+
+# Copy dependency files first to leverage Docker cache
+COPY go.mod  ./
+
+# Copy source code
+COPY . .
+
+# Build the application
+RUN go build -o server .
+
+
+# Runtime stage
+FROM alpine:3.20
+
+# Create a non-root user
+RUN adduser -D appuser
+
+WORKDIR /app
+
+# Copy the compiled binary
+COPY --from=builder /app/server .
+
+# Run as non-root user
+USER appuser
+
+# Document the application port
+EXPOSE 8080
+
+# Start the application
+CMD ["./server"]

q1-deploy-monitor/app/go.mod

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+module q1-deploy-monitor
+
+go 1.26.5

q1-deploy-monitor/app/main.go

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+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"sync/atomic"
+)
+
+// Stores the total number of API requests.
+var requestCount uint64
+
+func main() {
+	// Register API endpoints
+	http.HandleFunc("/", requestCounter(helloHandler))
+	http.HandleFunc("/health", requestCounter(healthHandler))
+	http.HandleFunc("/metrics", metricsHandler)
+
+	// Start server on port 8080
+	fmt.Println("Server is running on port 8080")
+	log.Fatal(http.ListenAndServe(":8080", nil))
+}
+
+// Middleware that counts API requests.
+// The /metrics endpoint is not wrapped with this middleware,
+// so requests to /metrics are not included in the counter.
+func requestCounter(next http.HandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		atomic.AddUint64(&requestCount, 1)
+		next(w, r)
+	}
+}
+
+// Adds CORS headers to allow the dashboard to access the API.
+func enableCORS(w http.ResponseWriter) {
+	w.Header().Set("Access-Control-Allow-Origin", "*")
+	w.Header().Set("Access-Control-Allow-Methods", "GET, OPTIONS")
+	w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+}
+
+// Root endpoint
+func helloHandler(w http.ResponseWriter, r *http.Request) {
+	enableCORS(w)
+
+	// Handle browser CORS preflight requests
+	if r.Method == http.MethodOptions {
+		w.WriteHeader(http.StatusNoContent)
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+
+	json.NewEncoder(w).Encode(map[string]string{
+		"message": "Hello, World!",
+	})
+}
+
+// Health check endpoint
+func healthHandler(w http.ResponseWriter, r *http.Request) {
+	enableCORS(w)
+
+	// Handle browser CORS preflight requests
+	if r.Method == http.MethodOptions {
+		w.WriteHeader(http.StatusNoContent)
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+
+	json.NewEncoder(w).Encode(map[string]string{
+		"status": "healthy",
+	})
+}
+
+// Metrics endpoint
+// This endpoint does NOT increment the request counter.
+func metricsHandler(w http.ResponseWriter, r *http.Request) {
+	enableCORS(w)
+
+	// Handle browser CORS preflight requests
+	if r.Method == http.MethodOptions {
+		w.WriteHeader(http.StatusNoContent)
+		return
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+
+	json.NewEncoder(w).Encode(map[string]uint64{
+		"requests": atomic.LoadUint64(&requestCount),
+	})
+}