Prometheus encoder added similar to hostd

autopilot/autopilot.go

@@ -18,6 +18,7 @@
 	"go.sia.tech/renterd/api"
 	"go.sia.tech/renterd/build"
 	"go.sia.tech/renterd/hostdb"
+	"go.sia.tech/renterd/internal/prometheus"
 	"go.sia.tech/renterd/object"
 	"go.sia.tech/renterd/wallet"
 	"go.sia.tech/renterd/webhooks"
@@ -175,6 +176,34 @@
 	})
 }
 
+func (ap *Autopilot) writeResponse(c jape.Context, code int, resp any) {
+	var responseFormat string
+	if err := c.DecodeForm("response", &responseFormat); err != nil {
+		return
+	}
+
+	if resp != nil {
+		switch responseFormat {
+		case "prometheus":
+			v, ok := resp.(prometheus.Marshaller)
+			if !ok {
+				err := fmt.Errorf("response does not implement prometheus.Marshaller %T", resp)
+				c.Error(err, http.StatusInternalServerError)
+				ap.logger.Error("response does not implement prometheus.Marshaller", zap.Stack("stack"), zap.Error(err))
+				return
+			}
+
+			enc := prometheus.NewEncoder(c.ResponseWriter)
+			if err := enc.Append(v); err != nil {
+				ap.logger.Error("failed to marshal prometheus response", zap.Error(err))
+				return
+			}
+		default:
+			c.Encode(resp)
+		}
+	}
+}
+
 func (ap *Autopilot) configHandlerPOST(jc jape.Context) {
 	ctx := jc.Request.Context()
 
@@ -691,7 +720,7 @@
 	jc.Encode(host)
 }
 
 func (ap *Autopilot) stateHandlerGET(jc jape.Context) {
 	pruning, pLastStart := ap.c.Status()
 	migrating, mLastStart := ap.m.Status()
 	scanning, sLastStart := ap.s.Status()
@@ -701,7 +730,7 @@
 		return
 	}
 
-	jc.Encode(api.AutopilotStateResponse{
+	ap.writeResponse(jc, http.StatusOK, AutopilotStateResp(api.AutopilotStateResponse{
 		Configured:         err == nil,
 		Migrating:          migrating,
 		MigratingLastStart: api.TimeRFC3339(mLastStart),
@@ -719,7 +748,7 @@
 			OS:        runtime.GOOS,
 			BuildTime: api.TimeRFC3339(build.BuildTime()),
 		},
-	})
+	}))
 }
 
 func (ap *Autopilot) hostsHandlerPOST(jc jape.Context) {

autopilot/prometheus.go

@@ -0,0 +1,66 @@
+package autopilot
+
+import (
+	"go.sia.tech/renterd/api"
+	"go.sia.tech/renterd/internal/prometheus"
+)
+
+type AutopilotStateResp api.AutopilotStateResponse
+
+func (asr AutopilotStateResp) PrometheusMetric() (metrics []prometheus.Metric) {
+	labels := map[string]any{
+		"network":   asr.Network,
+		"version":   asr.Version,
+		"commit":    asr.Commit,
+		"os":        asr.OS,
+		"buildTime": asr.BuildTime.String(),
+	}
+	// labels := fmt.Sprintf(`network="%s", version="%s", commit="%s", os="%s", buildTime="%s"`,
+	// build.NetworkName(), build.Version(), build.Commit(), runtime.GOOS, api.TimeRFC3339(build.BuildTime()))
+	metrics = append(metrics, prometheus.Metric{
+		Name:   "renterd_autopilot_state_uptime",
+		Labels: labels,
+		Value:  float64(asr.UptimeMS),
+	})
+	metrics = append(metrics, prometheus.Metric{
+		Name:   "renterd_autopilot_state_configured",
+		Labels: labels,
+		Value: func() float64 {
+			if asr.Configured {
+				return 1
+			}
+			return 0
+		}(),
+	})
+	metrics = append(metrics, prometheus.Metric{
+		Name:   "renterd_autopilot_state_migrating",
+		Labels: labels,
+		Value: func() float64 {
+			if asr.Migrating {
+				return 1
+			}
+			return 0
+		}(),
+	})
+	metrics = append(metrics, prometheus.Metric{
+		Name:   "renterd_autopilot_state_pruning",
+		Labels: labels,
+		Value: func() float64 {
+			if asr.Pruning {
+				return 1
+			}
+			return 0
+		}(),
+	})
+	metrics = append(metrics, prometheus.Metric{
+		Name:   "renterd_autopilot_state_scanning",
+		Labels: labels,
+		Value: func() float64 {
+			if asr.Scanning {
+				return 1
+			}
+			return 0
+		}(),
+	})
+	return
+}