feat: deliver authenticated merchant analytics API

internal/analytics/details.go

@@ -0,0 +1,132 @@
+package analytics
+
+import (
+	"context"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"strconv"
+	"time"
+
+	"github.com/jackc/pgx/v5"
+)
+
+type DetailFilter struct {
+	View         string
+	FailureStage string
+	TerminalID   string
+	Cursor       string
+	Limit        int
+}
+type Attempt struct {
+	Sequence     int        `json:"sequence"`
+	Status       string     `json:"status"`
+	CreatedAt    *time.Time `json:"createdAt"`
+	InitTimeMS   *int       `json:"initTimeMs"`
+	VerifyTimeMS *int       `json:"verifyTimeMs"`
+}
+type Detail struct {
+	SessionID     string     `json:"sessionId"`
+	TerminalID    string     `json:"terminalId"`
+	SessionStatus string     `json:"sessionStatus"`
+	AmountRial    int64      `json:"amountRial"`
+	FeeAmountRial int64      `json:"feeAmountRial"`
+	CreatedAt     time.Time  `json:"createdAt"`
+	ExpiresAt     *time.Time `json:"expiresAt"`
+	VerifiedAt    *time.Time `json:"verifiedAt"`
+	SettledAt     *time.Time `json:"settledAt"`
+	AttemptCount  int        `json:"attemptCount"`
+	FailureStage  *string    `json:"failureStage"`
+	Attempts      []Attempt  `json:"attempts"`
+}
+
+func (s *Service) Details(ctx context.Context, merchantID int64, period Period, filter DetailFilter) ([]Detail, string, error) {
+	if filter.Limit <= 0 {
+		filter.Limit = 25
+	}
+	if filter.Limit > 100 {
+		return nil, "", errors.New("analytics: detail limit exceeds 100")
+	}
+	offset := 0
+	if filter.Cursor != "" {
+		decoded, err := base64.RawURLEncoding.DecodeString(filter.Cursor)
+		if err != nil {
+			return nil, "", errors.New("analytics: invalid cursor")
+		}
+		offset, err = strconv.Atoi(string(decoded))
+		if err != nil || offset < 0 {
+			return nil, "", errors.New("analytics: invalid cursor")
+		}
+	}
+	statusPredicate := "ps.status='Paid'"
+	switch filter.View {
+	case "UNVERIFIED_PAID":
+		statusPredicate = "ps.status='Paid'"
+	case "FAILED":
+		statusPredicate = "ps.status='Failed'"
+	case "RETRIED":
+		statusPredicate = "(SELECT count(*) FROM payment_attempts x WHERE x.session_id=ps.id)>1"
+	default:
+		return nil, "", errors.New("analytics: invalid detail view")
+	}
+	query := `SELECT ps.id,ps.source_key,t.source_key,ps.status,ps.amount_rial,ps.fee_amount_rial,ps.created_at,ps.expires_at,ps.verified_at,ps.settled_at,
+	 count(pa.id)::int,coalesce(bool_or(pa.status='InBank'),false) FROM payment_sessions ps JOIN terminals t ON t.id=ps.terminal_id LEFT JOIN payment_attempts pa ON pa.session_id=ps.id
+	 WHERE ps.merchant_id=$1 AND ps.created_at>=$2 AND ps.created_at<$3 AND ` + statusPredicate + `
+	 AND ($4='' OR t.source_key=$4) GROUP BY ps.id,t.source_key ORDER BY ps.created_at DESC,ps.id DESC LIMIT $5 OFFSET $6`
+	rows, err := s.pool.Query(ctx, query, merchantID, period.StartAt, period.EndAt, filter.TerminalID, filter.Limit+1, offset)
+	if err != nil {
+		return nil, "", fmt.Errorf("querying session details: %w", err)
+	}
+	defer rows.Close()
+	details := make([]Detail, 0, filter.Limit)
+	ids := make([]int64, 0, filter.Limit)
+	for rows.Next() {
+		var id int64
+		var reachedBank bool
+		var d Detail
+		if err := rows.Scan(&id, &d.SessionID, &d.TerminalID, &d.SessionStatus, &d.AmountRial, &d.FeeAmountRial, &d.CreatedAt, &d.ExpiresAt, &d.VerifiedAt, &d.SettledAt, &d.AttemptCount, &reachedBank); err != nil {
+			return nil, "", fmt.Errorf("scanning session detail: %w", err)
+		}
+		d.SessionID = "ses_" + d.SessionID
+		d.Attempts = []Attempt{}
+		if d.SessionStatus == "Failed" {
+			stage := "OTHER_OBSERVED"
+			if d.AttemptCount == 0 {
+				stage = "NO_ATTEMPT"
+			} else if reachedBank {
+				stage = "REACHED_BANK"
+			}
+			d.FailureStage = &stage
+			if filter.FailureStage != "" && filter.FailureStage != stage {
+				continue
+			}
+		}
+		if len(details) < filter.Limit {
+			details = append(details, d)
+			ids = append(ids, id)
+		}
+	}
+	if err := rows.Err(); err != nil {
+		return nil, "", fmt.Errorf("iterating session details: %w", err)
+	}
+	for i, id := range ids {
+		attemptRows, err := s.pool.Query(ctx, `SELECT sequence,status,created_at,init_time_ms,verify_time_ms FROM payment_attempts WHERE session_id=$1 ORDER BY sequence`, id)
+		if err != nil {
+			return nil, "", fmt.Errorf("querying attempts: %w", err)
+		}
+		attempts, err := pgx.CollectRows(attemptRows, func(row pgx.CollectableRow) (Attempt, error) {
+			var a Attempt
+			err := row.Scan(&a.Sequence, &a.Status, &a.CreatedAt, &a.InitTimeMS, &a.VerifyTimeMS)
+			return a, err
+		})
+		if err != nil {
+			return nil, "", fmt.Errorf("collecting attempts: %w", err)
+		}
+		details[i].Attempts = attempts
+	}
+	next := ""
+	if len(details) == filter.Limit {
+		next = base64.RawURLEncoding.EncodeToString([]byte(strconv.Itoa(offset + filter.Limit)))
+	}
+	return details, next, nil
+}