improved logging for debug

internal/report.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"log/slog"
 	"time"
 
 	"github.com/shopspring/decimal"
@@ -58,10 +59,21 @@ type Selector func(Record) bool
 func BuildReport(ctx context.Context, reader RecordReader, writer ReportWriter, s Selector) error {
 	buys := make(map[string]*FillerQueue)
 
+	var buysCount, sellsCount int64
+	var lastTimestamp time.Time
+	progTicker := time.NewTicker(10 * time.Second)
+
 	for {
 		select {
 		case <-ctx.Done():
 			return ctx.Err()
+		case <-progTicker.C:
+			slog.InfoContext(ctx, "Progress update",
+				slog.Int64("total_records", buysCount+sellsCount),
+				slog.Int64("sell_records", sellsCount),
+				slog.Int64("buy_records", buysCount),
+				slog.Time("last_record_timestamp", lastTimestamp),
+			)
 		default:
 			rec, err := reader.ReadRecord(ctx)
 			if err != nil {
@@ -72,9 +84,21 @@ func BuildReport(ctx context.Context, reader RecordReader, writer ReportWriter,
 			}
 
 			if !s(rec) {
+				slog.Debug("Report: skipping record",
+					slog.String("symbol", rec.Symbol()),
+					slog.String("side", rec.Side().String()),
+				)
 				continue
 			}
 
+			if rec.Side().IsBuy() {
+				buysCount++
+			} else {
+				sellsCount++
+			}
+
+			lastTimestamp = rec.Timestamp()
+
 			buyQueue, ok := buys[rec.Symbol()]
 			if !ok {
 				buyQueue = new(FillerQueue)
@@ -85,11 +109,17 @@ func BuildReport(ctx context.Context, reader RecordReader, writer ReportWriter,
 			if err != nil {
 				return fmt.Errorf("processing record: %w", err)
 			}
+
 		}
 	}
 }
 
 func processRecord(ctx context.Context, q *FillerQueue, rec Record, writer ReportWriter) error {
+	slog.Debug("Report: processing record",
+		slog.String("symbol", rec.Symbol()),
+		slog.String("side", rec.Side().String()),
+	)
+
 	switch rec.Side() {
 	case SideBuy:
 		q.Push(NewFiller(rec))