Files
pad/internal/store/comments.go
T
xarmian 6e4c7f617b fix(timeline): drop \xff cursor sentinel that broke Postgres pagination (BUG-1086) (#391)
The timeline handler defaulted the cursor's beforeID to the literal byte
"\xff" as a sentinel intended to "sort after any UUID". SQLite tolerates
that in TEXT columns, but Postgres rejects it as an invalid UTF-8 byte
sequence (SQLSTATE 22021 — "invalid byte sequence for encoding 'UTF8':
0xff"), causing every timeline tab load on pad cloud to return 500.

Reproduced empirically against the test Postgres with a one-line probe
that issues a TEXT-typed bind of "\xff" — same error string the bug
reported.

The fix removes the sentinel and distinguishes three cursor cases in
the handler:

  1. Neither `before` nor `before_id` (true first page) → store gets
     beforeID = "" and drops the id tie-breaker from the WHERE clause
     entirely. Just `WHERE created_at < ?`.

  2. Both supplied (normal cursor pagination) → unchanged.

  3. `before` supplied without `before_id` (anomalous but possible
     for external clients) → use "g" as a UUID-safe upper-bound
     sentinel. Lowercase-hex UUIDs are bounded by "f", so "g" sorts
     above them in every reasonable collation while remaining valid
     UTF-8. This preserves the legacy semantics of including
     same-second rows that the naive `created_at < ?` would drop —
     a regression Codex caught on round 1 of review.

The id-predicate branching is applied symmetrically across all three
*BeforeTime store functions: ListCommentsBeforeTime,
ListDocumentActivityBeforeTime, ListItemVersionsBeforeTime.

New test file internal/store/timeline_pagination_test.go covers:

  - No-cursor first-page path (the broken one)
  - Real (timestamp, id) cursor pagination
  - Same-second cursor with sentinel id (regression guard)
  - Limit respected
  - Activity and version BeforeTime no-cursor paths

All six pass on SQLite and on real Postgres via `make test-pg`. Full
./internal/store and ./internal/server suites stay green on Postgres.
2026-05-03 00:12:50 -04:00

175 lines
5.2 KiB
Go

package store
import (
"database/sql"
"fmt"
"time"
"github.com/PerpetualSoftware/pad/internal/models"
)
// CreateComment adds a new comment to an item.
func (s *Store) CreateComment(workspaceID, itemID string, input models.CommentCreate) (*models.Comment, error) {
id := newID()
ts := now()
createdBy := input.CreatedBy
if createdBy == "" {
createdBy = "user"
}
source := input.Source
if source == "" {
source = "web"
}
author := input.Author
if author == "" {
author = createdBy
}
_, err := s.db.Exec(s.q(`
INSERT INTO comments (id, item_id, workspace_id, author, body, created_by, source, activity_id, parent_id, created_at, updated_at)
VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`),
id, itemID, workspaceID, author, input.Body, createdBy, source,
nilIfEmpty(input.ActivityID), nilIfEmpty(input.ParentID), ts, ts,
)
if err != nil {
return nil, fmt.Errorf("insert comment: %w", err)
}
return s.GetComment(id)
}
// GetComment returns a single comment by ID.
func (s *Store) GetComment(id string) (*models.Comment, error) {
row := s.db.QueryRow(s.q(`
SELECT c.id, c.item_id, c.workspace_id, c.author, c.body,
c.created_by, c.source, COALESCE(c.activity_id, ''), COALESCE(c.parent_id, ''),
c.created_at, c.updated_at,
i.title, i.slug
FROM comments c
JOIN items i ON i.id = c.item_id
WHERE c.id = ?`), id)
var c models.Comment
var createdAt, updatedAt string
err := row.Scan(
&c.ID, &c.ItemID, &c.WorkspaceID, &c.Author, &c.Body,
&c.CreatedBy, &c.Source, &c.ActivityID, &c.ParentID,
&createdAt, &updatedAt,
&c.ItemTitle, &c.ItemSlug,
)
if err == sql.ErrNoRows {
return nil, nil
}
if err != nil {
return nil, fmt.Errorf("get comment: %w", err)
}
c.CreatedAt = parseTime(createdAt)
c.UpdatedAt = parseTime(updatedAt)
return &c, nil
}
// ListComments returns all comments for an item, ordered chronologically.
func (s *Store) ListComments(itemID string) ([]models.Comment, error) {
rows, err := s.db.Query(s.q(`
SELECT c.id, c.item_id, c.workspace_id, c.author, c.body,
c.created_by, c.source, COALESCE(c.activity_id, ''), COALESCE(c.parent_id, ''),
c.created_at, c.updated_at
FROM comments c
WHERE c.item_id = ?
ORDER BY c.created_at ASC`), itemID)
if err != nil {
return nil, fmt.Errorf("list comments: %w", err)
}
defer rows.Close()
var comments []models.Comment
for rows.Next() {
var c models.Comment
var createdAt, updatedAt string
if err := rows.Scan(
&c.ID, &c.ItemID, &c.WorkspaceID, &c.Author, &c.Body,
&c.CreatedBy, &c.Source, &c.ActivityID, &c.ParentID,
&createdAt, &updatedAt,
); err != nil {
return nil, fmt.Errorf("scan comment: %w", err)
}
c.CreatedAt = parseTime(createdAt)
c.UpdatedAt = parseTime(updatedAt)
comments = append(comments, c)
}
return comments, rows.Err()
}
// ListCommentsBeforeTime returns comments for an item created before the given time,
// ordered newest-first, limited to `limit` results. Used for cursor-based timeline pagination.
//
// When beforeID is empty (first page / no cursor), the secondary id tie-breaker
// is omitted. Earlier code passed a "\xff" sentinel intended to sort after any
// UUID, but Postgres rejects that as an invalid UTF-8 byte sequence in a TEXT
// bind parameter (SQLSTATE 22021). See BUG-1086.
func (s *Store) ListCommentsBeforeTime(itemID string, before time.Time, beforeID string, limit int) ([]models.Comment, error) {
ts := before.Format(time.RFC3339)
const selectCols = `c.id, c.item_id, c.workspace_id, c.author, c.body,
c.created_by, c.source, COALESCE(c.activity_id, ''), COALESCE(c.parent_id, ''),
c.created_at, c.updated_at`
const orderLimit = `ORDER BY c.created_at DESC, c.id DESC LIMIT ?`
var rows *sql.Rows
var err error
if beforeID == "" {
rows, err = s.db.Query(s.q(`
SELECT `+selectCols+`
FROM comments c
WHERE c.item_id = ? AND c.created_at < ?
`+orderLimit), itemID, ts, limit)
} else {
rows, err = s.db.Query(s.q(`
SELECT `+selectCols+`
FROM comments c
WHERE c.item_id = ? AND (c.created_at < ? OR (c.created_at = ? AND c.id < ?))
`+orderLimit), itemID, ts, ts, beforeID, limit)
}
if err != nil {
return nil, fmt.Errorf("list comments before time: %w", err)
}
defer rows.Close()
var comments []models.Comment
for rows.Next() {
var c models.Comment
var createdAt, updatedAt string
if err := rows.Scan(
&c.ID, &c.ItemID, &c.WorkspaceID, &c.Author, &c.Body,
&c.CreatedBy, &c.Source, &c.ActivityID, &c.ParentID,
&createdAt, &updatedAt,
); err != nil {
return nil, fmt.Errorf("scan comment: %w", err)
}
c.CreatedAt = parseTime(createdAt)
c.UpdatedAt = parseTime(updatedAt)
comments = append(comments, c)
}
return comments, rows.Err()
}
// DeleteComment removes a comment by ID.
func (s *Store) DeleteComment(id string) error {
result, err := s.db.Exec(s.q("DELETE FROM comments WHERE id = ?"), id)
if err != nil {
return fmt.Errorf("delete comment: %w", err)
}
n, _ := result.RowsAffected()
if n == 0 {
return sql.ErrNoRows
}
return nil
}
// CountComments returns the number of comments for an item.
func (s *Store) CountComments(itemID string) (int, error) {
var count int
err := s.db.QueryRow(s.q("SELECT COUNT(*) FROM comments WHERE item_id = ?"), itemID).Scan(&count)
return count, err
}