postgres: refactor status getters

Signed-off-by: Hank Donnay <hdonnay@redhat.com>

notifier/postgres/get_status.go

@@ -0,0 +1,140 @@
+package postgres
+
+import (
+	"context"
+
+	"github.com/google/uuid"
+	"github.com/jackc/pgx/v4"
+	"github.com/jackc/pgx/v4/pgxpool"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+)
+
+var (
+	createdCounter = promauto.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "clair",
+			Subsystem: "notifier",
+			Name:      "created_total",
+			Help:      "Total number of database queries issued in the created method",
+		},
+		[]string{"query", "error"},
+	)
+	createdDuration = promauto.NewHistogramVec(
+		prometheus.HistogramOpts{
+			Namespace: "clair",
+			Subsystem: "notifier",
+			Name:      "created_duration_seconds",
+			Help:      "Duration of all queries issued in the created method",
+		},
+		[]string{"query", "error"},
+	)
+	failedCounter = promauto.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "clair",
+			Subsystem: "notifier",
+			Name:      "failed_total",
+			Help:      "Total number of database queries issued in the failed method",
+		},
+		[]string{"query", "error"},
+	)
+	failedDuration = promauto.NewHistogramVec(
+		prometheus.HistogramOpts{
+			Namespace: "clair",
+			Subsystem: "notifier",
+			Name:      "failed_duration_seconds",
+			Help:      "Duration of all queries issued in the failed method",
+		},
+		[]string{"query", "error"},
+	)
+	deletedCounter = promauto.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "clair",
+			Subsystem: "notifier",
+			Name:      "deleted_total",
+			Help:      "Total number of database queries issued in the deleted method",
+		},
+		[]string{"query", "error"},
+	)
+	deletedDuration = promauto.NewHistogramVec(
+		prometheus.HistogramOpts{
+			Namespace: "clair",
+			Subsystem: "notifier",
+			Name:      "deleted_duration_seconds",
+			Help:      "Duration of all queries issued in the deleted method",
+		},
+		[]string{"query", "error"},
+	)
+)
+
+func (s *Store) getStatus(ctx context.Context, status string, m statusMetrics) ([]uuid.UUID, error) {
+	const (
+		query = `SELECT notification_id FROM receipt WHERE status = $1::receiptstatus;`
+	)
+
+	ids := []uuid.UUID{}
+	err := s.pool.AcquireFunc(ctx, func(c *pgxpool.Conn) error {
+		var err error
+		var rows pgx.Rows
+		timer := prometheus.NewTimer(prometheus.ObserverFunc(func(v float64) {
+			m.dur.WithLabelValues(`query`, errLabel(err)).Observe(v)
+		}))
+		defer timer.ObserveDuration()
+		rows, err = c.Query(ctx, query, status)
+		m.counter.WithLabelValues(`query`, errLabel(err)).Add(1)
+		if err != nil {
+			return err
+		}
+		var id uuid.UUID
+		for rows.Next() {
+			if err := rows.Scan(&id); err != nil {
+				return err
+			}
+			ids = append(ids, id)
+		}
+		if err := rows.Err(); err != nil {
+			return err
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return ids, nil
+}
+
+// Created will return all notification ids in "created" status.
+func (s *Store) Created(ctx context.Context) ([]uuid.UUID, error) {
+	ids, err := s.getStatus(ctx, `created`, statusMetrics{
+		counter: createdCounter,
+		dur:     createdDuration,
+	})
+	if err != nil {
+		return nil, err
+	}
+	return ids, nil
+}
+
+// Failed will return all notification ids in "delivery_failed" status.
+func (s *Store) Failed(ctx context.Context) ([]uuid.UUID, error) {
+	ids, err := s.getStatus(ctx, `delivery_failed`, statusMetrics{
+		counter: failedCounter,
+		dur:     failedDuration,
+	})
+	if err != nil {
+		return nil, err
+	}
+	return ids, nil
+}
+
+// Deleted will return all notification ids in "deleted" status.
+func (s *Store) Deleted(ctx context.Context) ([]uuid.UUID, error) {
+	ids, err := s.getStatus(ctx, `deleted`, statusMetrics{
+		counter: deletedCounter,
+		dur:     deletedDuration,
+	})
+	if err != nil {
+		return nil, err
+	}
+	return ids, nil
+}