owpengram-server/internal/app/moderation/appeal_links.go
2026-07-24 11:56:59 +08:00

83 lines
2.9 KiB
Go

package moderation
import (
"context"
"crypto/rand"
"crypto/sha256"
"encoding/base64"
"errors"
"fmt"
"time"
"telesrv/internal/domain"
)
const moderationAppealTokenBytes = 32
// IssueAppealLink creates a hash-only, time-bounded bearer capability. The raw
// token is returned once and must only be embedded in the affected user's
// client-visible appeal URL.
func (s *Service) IssueAppealLink(ctx context.Context, caseID, appellantUserID int64, expiresAt, now time.Time) (string, error) {
if s == nil || s.cases == nil {
return "", fmt.Errorf("moderation case store is not configured")
}
for attempt := 0; attempt < 3; attempt++ {
raw := make([]byte, moderationAppealTokenBytes)
if _, err := rand.Read(raw); err != nil {
return "", fmt.Errorf("generate moderation appeal token: %w", err)
}
token := base64.RawURLEncoding.EncodeToString(raw)
link := domain.ModerationAppealLink{
CaseID: caseID, AppellantUserID: appellantUserID,
TokenHash: sha256.Sum256(raw), ExpiresAt: expiresAt.UTC(),
CreatedAt: now.UTC(),
}
if _, err := s.cases.IssueModerationAppealLink(ctx, link); err == nil {
return token, nil
} else if !errors.Is(err, domain.ErrModerationActionConflict) {
return "", err
}
}
return "", domain.ErrModerationActionConflict
}
func (s *Service) ResolveAppealLink(ctx context.Context, token string, now time.Time) (domain.ModerationAppealLink, bool, error) {
if s == nil || s.cases == nil {
return domain.ModerationAppealLink{}, false, fmt.Errorf("moderation case store is not configured")
}
hash, err := moderationAppealTokenHash(token)
if err != nil {
return domain.ModerationAppealLink{}, false, err
}
return s.cases.GetModerationAppealLink(ctx, hash, now.UTC())
}
func (s *Service) Appeal(ctx context.Context, appealID int64) (domain.ModerationAppeal, bool, error) {
if s == nil || s.cases == nil {
return domain.ModerationAppeal{}, false, fmt.Errorf("moderation case store is not configured")
}
return s.cases.GetModerationAppeal(ctx, appealID)
}
func (s *Service) SubmitAppealLink(ctx context.Context, token, text string, now time.Time) (domain.ModerationAppeal, bool, error) {
if s == nil || s.cases == nil {
return domain.ModerationAppeal{}, false, fmt.Errorf("moderation case store is not configured")
}
hash, err := moderationAppealTokenHash(token)
if err != nil {
return domain.ModerationAppeal{}, false, err
}
return s.cases.SubmitModerationAppealByLink(ctx, hash, text, now.UTC())
}
func moderationAppealTokenHash(token string) ([sha256.Size]byte, error) {
if len(token) != base64.RawURLEncoding.EncodedLen(moderationAppealTokenBytes) {
return [sha256.Size]byte{}, domain.ErrModerationAppealLinkInvalid
}
raw, err := base64.RawURLEncoding.DecodeString(token)
if err != nil || len(raw) != moderationAppealTokenBytes ||
base64.RawURLEncoding.EncodeToString(raw) != token {
return [sha256.Size]byte{}, domain.ErrModerationAppealLinkInvalid
}
return sha256.Sum256(raw), nil
}