mock amazon event processing stubbed

2026-08-20 00:35:13 -06:00
parent f5a3d2594d
commit 16ecf2dc66
4 changed files with 622 additions and 3 deletions
@@ -0,0 +1,183 @@
+package amazon
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"ruben/inventory2/logging"
+	"time"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+type (
+	Mocks struct {
+		log *logging.Logger
+		db  *pgxpool.Pool
+	}
+
+	event struct {
+		ShopID         string
+		EventTimestamp time.Time
+		EventID        string
+	}
+)
+
+const (
+	eventChannelName = "mock_shop_amazon_event_inserted"
+)
+
+func NewMocks(log *logging.Logger, db *pgxpool.Pool) *Mocks {
+	return &Mocks{
+		log: log,
+		db:  db,
+	}
+}
+
+func (m *Mocks) ProcessEvents(ctx context.Context) error {
+	notifCh, errCh := m.listenForNotifications(ctx)
+
+	for {
+		m.log.Debug("processing events")
+		if err := m.processUnprocessedEvents(ctx); err != nil {
+			if errors.Is(err, context.Canceled) {
+				return nil
+			}
+			return fmt.Errorf("error occurred while processing events: %w", err)
+		}
+
+		select {
+		case <-ctx.Done():
+			return nil
+		case err := <-errCh:
+			return err
+		case _, ok := <-notifCh:
+			if !ok {
+				return <-errCh
+			}
+		case <-time.After(time.Minute):
+		}
+	}
+}
+
+func (m *Mocks) listenForNotifications(ctx context.Context) (<-chan struct{}, <-chan error) {
+	errCh := make(chan error, 1)
+
+	pc, err := m.db.Acquire(ctx)
+	if err != nil {
+		errCh <- fmt.Errorf("failed to acquire a connection: %w", err)
+		return nil, errCh
+	}
+
+	conn := pc.Conn()
+
+	if _, err := conn.Exec(ctx, fmt.Sprintf("LISTEN %s", eventChannelName)); err != nil {
+		errCh <- fmt.Errorf("failed to start listening for notifications: %w", err)
+		return nil, errCh
+	}
+
+	ch := make(chan struct{})
+
+	go func() (err error) {
+		defer func() {
+			pc.Release()
+			if err != nil {
+				errCh <- err
+			}
+			close(ch)
+			close(errCh)
+		}()
+
+		for {
+			if _, err := conn.WaitForNotification(ctx); err != nil {
+				if errors.Is(err, context.Canceled) {
+					return nil
+				}
+				return fmt.Errorf("error occurred while waiting for the next notification: %w", err)
+			}
+
+			ch <- struct{}{}
+		}
+	}()
+
+	return ch, errCh
+}
+
+func (m *Mocks) processUnprocessedEvents(ctx context.Context) error {
+	for done := false; !done; {
+		err := pgx.BeginFunc(ctx, m.db, func(tx pgx.Tx) error {
+			rows, err := m.db.Query(
+				ctx,
+				`
+					SELECT
+						shop_id AS shopid,
+						event_id AS eventid,
+						event_timestamp AS eventtimestamp
+					FROM
+						mock.shop_amazon_events
+					WHERE
+						NOT processed
+					ORDER BY
+						shop_id, event_timestamp
+					LIMIT
+						100
+				`,
+			)
+			if err != nil {
+				return fmt.Errorf("failed to to perform query: %w", err)
+			}
+
+			evts, err := pgx.CollectRows(rows, pgx.RowToStructByNameLax[event])
+			if err != nil {
+				return fmt.Errorf("failed to scan rows: %w", err)
+			}
+
+			for _, e := range evts {
+				if err := m.processEvent(ctx, tx, e); err != nil {
+					return fmt.Errorf("failed to process event: %w", err)
+				}
+			}
+
+			if done = len(evts) == 0; !done {
+				m.log.Infof("processed %d events", len(evts))
+			}
+
+			return nil
+		})
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (m *Mocks) processEvent(ctx context.Context, tx pgx.Tx, e event) error {
+	m.log.Debugf("processing (mock) event: %#v", e)
+
+	_, err := tx.Exec(
+		ctx,
+		`
+			UPDATE
+				mock.shop_amazon_events
+			SET
+				processed = true,
+				processed_successfully = true
+			WHERE
+				shop_id = @shop_id
+				AND event_id = @event_id
+				AND event_timestamp = @event_timestamp
+		`,
+		pgx.NamedArgs{
+			"shop_id":         e.ShopID,
+			"event_id":        e.EventID,
+			"event_timestamp": e.EventTimestamp,
+		},
+	)
+	if err != nil {
+		return fmt.Errorf("failed to perform query: %w", err)
+	}
+
+	return nil
+}