1 files changed, 85 insertions, 0 deletions
diff --git a/internal/metrics/generator.go b/internal/metrics/generator.go
new file mode 100644
index 0000000..c85906a
--- /dev/null
+++ b/internal/metrics/generator.go
@@ -0,0 +1,85 @@
+package metrics
+
+import (
+	"math/rand"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const (
+	minTemperature = 15.0
+	maxTemperature = 35.0
+	maxConnections = 100
+	maxRequests    = 10
+)
+
+var (
+	jobTypes = []string{"email", "report", "backup"}
+	statuses = []string{"success", "failed"}
+)
+
+// Collectors holds Prometheus metric collectors for realtime mode
+type Collectors struct {
+	RequestsTotal      prometheus.Counter
+	ActiveConnections  prometheus.Gauge
+	TemperatureCelsius prometheus.Gauge
+	RequestDuration    prometheus.Histogram
+	JobsProcessed      *prometheus.CounterVec
+}
+
+// NewCollectors creates new Prometheus metric collectors for testing.
+// All metrics are prefixed with "epimetheus_test_" to clearly indicate
+// they are generated by the prometheus-pusher test/demo functionality.
+func NewCollectors() Collectors {
+	return Collectors{
+		RequestsTotal: prometheus.NewCounter(
+			prometheus.CounterOpts{
+				Name: "epimetheus_test_requests_total",
+				Help: "Total number of requests processed (test metric)",
+			},
+		),
+		ActiveConnections: prometheus.NewGauge(
+			prometheus.GaugeOpts{
+				Name: "epimetheus_test_active_connections",
+				Help: "Number of currently active connections (test metric)",
+			},
+		),
+		TemperatureCelsius: prometheus.NewGauge(
+			prometheus.GaugeOpts{
+				Name: "epimetheus_test_temperature_celsius",
+				Help: "Current temperature in Celsius (test metric)",
+			},
+		),
+		RequestDuration: prometheus.NewHistogram(
+			prometheus.HistogramOpts{
+				Name:    "epimetheus_test_request_duration_seconds",
+				Help:    "Histogram of request duration in seconds (test metric)",
+				Buckets: prometheus.DefBuckets,
+			},
+		),
+		JobsProcessed: prometheus.NewCounterVec(
+			prometheus.CounterOpts{
+				Name: "epimetheus_test_jobs_processed_total",
+				Help: "Total number of jobs processed by type (test metric)",
+			},
+			[]string{"job_type", "status"},
+		),
+	}
+}
+
+// Simulate generates random metric values for the collectors
+func (c Collectors) Simulate() {
+	c.RequestsTotal.Add(float64(rand.Intn(maxRequests) + 1))
+	c.ActiveConnections.Set(float64(rand.Intn(maxConnections)))
+	c.TemperatureCelsius.Set(minTemperature + rand.Float64()*(maxTemperature-minTemperature))
+
+	for i := 0; i < rand.Intn(5)+1; i++ {
+		duration := rand.Float64() * 2
+		c.RequestDuration.Observe(duration)
+	}
+
+	for _, jobType := range jobTypes {
+		status := statuses[rand.Intn(len(statuses))]
+		c.JobsProcessed.WithLabelValues(jobType, status).Add(float64(rand.Intn(5)))
+	}
+}