Files
archivmail/internal/storage/subject_charset_backfill.go
T
sysopsandClaude Sonnet 5 8f46d688a8 feat(PROJ-85): Fix undeklarierte 8-Bit-Zeichen in Header/Body ohne Encoded-Word
Getrennt von PROJ-84: Header (v.a. Subject) mit rohen 8-Bit-Bytes ohne
RFC-2047-Encoded-Word-Syntax wurden nicht auf tatsächliches Charset
geprüft, landeten als ungültiges UTF-8 in emails.subject und Manticore.
Gleiche Lücke bei decodeCharset() für den Body ohne verwertbaren
Content-Type.

RepairUTF8/RepairUTF8Bytes (charset_repair.go): bytegenaue Reparatur,
gültiges UTF-8 bleibt Identität, nur ungültige Byte-Sequenzen fallen
auf Windows-1252 zurück. Attachment.Data bewusst ausgenommen (bleibt
byte-exakt für Downloads). fix-subjects-Kommando erkennt jetzt beide
Fälle (HasEncodedWord || NeedsCharsetRepair).

Verifiziert auf 192.168.1.132: 54 zusätzliche Subject-Fälle, 219
Body-Fälle behoben (bodyInvalidUTF8 219 -> 0). --apply noch nicht
ausgeführt, Body-Korrektur braucht zusätzlich reindex.

Die ursprünglich gemeldete Amazon-Mail bleibt bewusst unverändert:
Encoding-Fehler kam bereits so vom Absender (=3F statt =DC im
Original-Encoded-Word), GoBD verbietet nachträgliche Korrektur
archivierter Originalinhalte.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WapWkrQusDuBMhaN8WyuXB
2026-08-06 20:46:58 +02:00

67 lines
2.3 KiB
Go

package storage
import (
"context"
"fmt"
)
// ListNonASCIISubjects returns emails whose subject contains at least one
// non-ASCII byte.
//
// Why a second lister next to ListRawEncodedSubjects: that one only matches the
// RFC 2047 encoded-word pattern (`=?charset?B|Q?...?=`) and therefore cannot
// find the second mojibake class at all — headers that were written with raw
// 8-bit Windows-1252/ISO-8859-1 bytes and no encoded-word syntax. Those rows
// contain no `=?...?=` marker; the only cheap SQL signal is "has bytes > 0x7F".
//
// The prefilter is `subject ~ '[^[:ascii:]]'`. Note that the obvious
// alternative `octet_length(subject) <> length(subject)` is WRONG here: in a
// SQL_ASCII database (which the production archive uses) length() counts bytes,
// so that condition is never true and the query silently returns nothing.
// The regex class works byte-wise in SQL_ASCII and char-wise in UTF8.
//
// The caller must narrow the result down with mailparser.NeedsCharsetRepair —
// the vast majority of non-ASCII subjects are perfectly valid UTF-8 and must
// not be touched.
//
// tenantID nil = all tenants. limit <= 0 = no limit.
func (s *Store) ListNonASCIISubjects(ctx context.Context, tenantID *int64, limit int) ([]SubjectRow, error) {
if s.db == nil {
return nil, fmt.Errorf("storage: list non-ascii subjects: no database configured")
}
query := `SELECT id, tenant_id, COALESCE(subject, '')
FROM emails
WHERE subject IS NOT NULL
AND subject ~ '[^[:ascii:]]'`
args := []interface{}{}
if tenantID != nil {
args = append(args, *tenantID)
query += fmt.Sprintf(" AND tenant_id = $%d", len(args))
}
query += " ORDER BY received_at ASC"
if limit > 0 {
args = append(args, limit)
query += fmt.Sprintf(" LIMIT $%d", len(args))
}
rows, err := s.db.Query(ctx, query, args...)
if err != nil {
return nil, fmt.Errorf("storage: list non-ascii subjects: %w", err)
}
defer rows.Close()
var out []SubjectRow
for rows.Next() {
var r SubjectRow
if err := rows.Scan(&r.ID, &r.TenantID, &r.Subject); err != nil {
return nil, fmt.Errorf("storage: list non-ascii subjects: scan: %w", err)
}
out = append(out, r)
}
if err := rows.Err(); err != nil {
return nil, fmt.Errorf("storage: list non-ascii subjects: rows: %w", err)
}
return out, nil
}