f-37: periph: add final touch #37

Signed-off-by: GnomeZworc <nicolas.boufidjeline@g3e.fr>

internal/prometheus/agent/collector.go

@@ -3,12 +3,13 @@ package agentmetrics
 import (
 	"strings"
 
+	"git.g3e.fr/syonad/two/internal/state"
 	"git.g3e.fr/syonad/two/pkg/db/kv"
 	"github.com/dgraph-io/badger/v4"
 	"github.com/prometheus/client_golang/prometheus"
 )
 
-var allStates = []string{"creating", "created", "deleting", "deleted"}
+var allStates = state.All()
 
 // AgentCollector implements prometheus.Collector and exposes agent metrics
 // by querying the BadgerDB on each scrape.
@@ -47,7 +48,7 @@ func (c *AgentCollector) Collect(ch chan<- prometheus.Metric) {
 // collectStates counts resources under the given DB prefix by their state value
 // and emits one gauge per state label.
 func (c *AgentCollector) collectStates(ch chan<- prometheus.Metric, prefix string, desc *prometheus.Desc) {
-	counts := make(map[string]float64, len(allStates))
+	counts := make(map[state.State]float64, len(allStates))
 	for _, s := range allStates {
 		counts[s] = 0
 	}
@@ -55,13 +56,18 @@ func (c *AgentCollector) collectStates(ch chan<- prometheus.Metric, prefix strin
 	items, err := kv.ListByPrefix(c.db, prefix)
 	if err == nil {
 		for key, val := range items {
-			if strings.HasSuffix(key, "/state") {
-				counts[val]++
+			if !strings.HasSuffix(key, "/state") {
+				continue
+			}
+			// Une valeur hors enum n'est pas comptée : la migration au
+			// démarrage les a toutes ramenées dans l'enum.
+			if s, err := state.Parse(val); err == nil {
+				counts[s]++
 			}
 		}
 	}
 
-	for _, state := range allStates {
-		ch <- prometheus.MustNewConstMetric(desc, prometheus.GaugeValue, counts[state], state)
+	for _, s := range allStates {
+		ch <- prometheus.MustNewConstMetric(desc, prometheus.GaugeValue, counts[s], string(s))
 	}
 }

internal/prometheus/agent/collector_test.go

@@ -0,0 +1,126 @@
+package agentmetrics
+
+import (
+	"strings"
+	"testing"
+
+	"git.g3e.fr/syonad/two/internal/state"
+	"git.g3e.fr/syonad/two/pkg/db/kv"
+
+	"github.com/dgraph-io/badger/v4"
+	"github.com/prometheus/client_golang/prometheus"
+	dto "github.com/prometheus/client_model/go"
+)
+
+func newTestDB(t *testing.T) *badger.DB {
+	t.Helper()
+	db := kv.InitDB(kv.Config{Path: t.TempDir()}, false)
+	t.Cleanup(func() { db.Close() })
+	return db
+}
+
+// collect exécute une collecte et retourne, par nom de métrique, la valeur de
+// chaque série indexée par son label state.
+func collect(t *testing.T, c *AgentCollector) map[string]map[string]float64 {
+	t.Helper()
+	ch := make(chan prometheus.Metric, 64)
+	c.Collect(ch)
+	close(ch)
+
+	out := map[string]map[string]float64{}
+	for m := range ch {
+		var pb dto.Metric
+		if err := m.Write(&pb); err != nil {
+			t.Fatalf("write metric: %v", err)
+		}
+		// Le fqName n'est pas exposé directement : il figure dans la
+		// représentation textuelle du Desc.
+		desc := m.Desc().String()
+		var name string
+		switch {
+		case strings.Contains(desc, "syonad_vpcs_total"):
+			name = "vpcs"
+		case strings.Contains(desc, "syonad_subnets_total"):
+			name = "subnets"
+		default:
+			t.Fatalf("métrique inattendue : %s", desc)
+		}
+		if out[name] == nil {
+			out[name] = map[string]float64{}
+		}
+		for _, l := range pb.GetLabel() {
+			if l.GetName() == "state" {
+				out[name][l.GetValue()] = pb.GetGauge().GetValue()
+			}
+		}
+	}
+	return out
+}
+
+func TestCollector_CountsByState(t *testing.T) {
+	db := newTestDB(t)
+	for resource, s := range map[string]state.State{
+		"vpc/vpc-1":   state.Running,
+		"vpc/vpc-2":   state.Running,
+		"vpc/vpc-3":   state.Error,
+		"subnet/sn-1": state.Creating,
+	} {
+		if err := state.Set(db, resource, s); err != nil {
+			t.Fatalf("préparation du test : %v", err)
+		}
+	}
+
+	got := collect(t, NewAgentCollector(db))
+	wantVPC := map[string]float64{"creating": 0, "running": 2, "error": 1, "deleting": 0, "deleted": 0}
+	for s, want := range wantVPC {
+		if got["vpcs"][s] != want {
+			t.Errorf("vpcs{state=%q} = %v, attendu %v", s, got["vpcs"][s], want)
+		}
+	}
+	if got["subnets"]["creating"] != 1 {
+		t.Errorf("subnets{state=creating} = %v, attendu 1", got["subnets"]["creating"])
+	}
+}
+
+// Une série par état doit être émise même à zéro : une métrique qui disparaît
+// côté Prometheus casse les alertes qui s'en servent.
+func TestCollector_EmitsEveryState(t *testing.T) {
+	got := collect(t, NewAgentCollector(newTestDB(t)))
+	for _, family := range []string{"vpcs", "subnets"} {
+		if len(got[family]) != len(state.All()) {
+			t.Errorf("%s : %d séries, attendu %d", family, len(got[family]), len(state.All()))
+		}
+		for _, s := range state.All() {
+			if _, ok := got[family][string(s)]; !ok {
+				t.Errorf("%s : série manquante pour l'état %q", family, s)
+			}
+		}
+	}
+}
+
+func TestCollector_IgnoresNonStateKeys(t *testing.T) {
+	db := newTestDB(t)
+	if err := state.Set(db, "vpc/vpc-1", state.Running); err != nil {
+		t.Fatalf("préparation du test : %v", err)
+	}
+	kv.AddInDB(db, "vpc/vpc-1/cidr", "10.0.0.0/16")
+
+	got := collect(t, NewAgentCollector(db))
+	if got["vpcs"]["running"] != 1 {
+		t.Errorf("vpcs{state=running} = %v, attendu 1", got["vpcs"]["running"])
+	}
+}
+
+func TestCollector_Describe(t *testing.T) {
+	ch := make(chan *prometheus.Desc, 10)
+	NewAgentCollector(newTestDB(t)).Describe(ch)
+	close(ch)
+
+	var n int
+	for range ch {
+		n++
+	}
+	if n != 2 {
+		t.Errorf("%d descripteurs, attendu 2", n)
+	}
+}