fix: port mailbox validation from im server

internal/httpapi/api.go

@@ -25,6 +25,11 @@ type API struct {
 
 const workbenchEventPublishTimeout = 15 * time.Second
 
+const (
+	maxMailboxSubjectLength = 200
+	maxMailboxContentLength = 5000
+)
+
 func New(st *store.Store, authenticator *auth.Authenticator, publisher events.Publisher) *API {
 	if publisher == nil {
 		publisher = events.NoopPublisher{}
@@ -879,9 +884,14 @@ func (a *API) mailboxSubmissions(w http.ResponseWriter, r *http.Request, p *auth
 	if !decodeBody(w, r, &body) {
 		return
 	}
+	subject := strings.TrimSpace(body.Subject)
+	content := strings.TrimSpace(body.Content)
+	if ok := validateMailboxSubmission(w, r, subject, content); !ok {
+		return
+	}
 	attachments, _ := json.Marshal(body.AttachmentFileIDs)
 	submission, err := a.store.CreateMailboxSubmission(r.Context(), p.UserID, store.MailboxSubmission{
-		SubmissionID: "mb_" + randomToken(12), Subject: strings.TrimSpace(body.Subject), Content: strings.TrimSpace(body.Content),
+		SubmissionID: "mb_" + randomToken(12), Subject: subject, Content: content,
 		Anonymous: body.Anonymous, AttachmentFileIDs: string(attachments), NoticeVersion: strings.TrimSpace(body.NoticeVersion),
 	}, idempotencyKey)
 	if err != nil {
@@ -896,6 +906,18 @@ func (a *API) mailboxSubmissions(w http.ResponseWriter, r *http.Request, p *auth
 	writeSuccess(w, r, mailboxSubmissionPayload(*submission))
 }
 
+func validateMailboxSubmission(w http.ResponseWriter, r *http.Request, subject, content string) bool {
+	if len([]rune(subject)) > maxMailboxSubjectLength {
+		writeError(w, r, http.StatusBadRequest, 30000, reasonValidationFailed, "validation failed", map[string]any{"field": "subject", "max_length": maxMailboxSubjectLength})
+		return false
+	}
+	if len([]rune(content)) > maxMailboxContentLength {
+		writeError(w, r, http.StatusBadRequest, 30000, reasonValidationFailed, "validation failed", map[string]any{"field": "content", "max_length": maxMailboxContentLength})
+		return false
+	}
+	return true
+}
+
 func (a *API) publishWorkbenchEvent(w http.ResponseWriter, r *http.Request, p *auth.Principal, module, action, resourceID string, targets []int64, title, summary string, data map[string]any) bool {
 	if a.events == nil {
 		return true

internal/httpapi/mailbox_test.go

@@ -0,0 +1,51 @@
+package httpapi
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"git.118im.com/im_team/im_workbench/internal/store"
+)
+
+func TestValidateMailboxSubmissionRejectsTooLongContent(t *testing.T) {
+	req := httptest.NewRequest(http.MethodPost, "/v1/workbench/executive-mailbox/submissions", nil)
+	rec := httptest.NewRecorder()
+
+	if validateMailboxSubmission(rec, req, "建议", strings.Repeat("a", maxMailboxContentLength+1)) {
+		t.Fatal("validateMailboxSubmission returned true for too-long content")
+	}
+	if rec.Code != http.StatusBadRequest {
+		t.Fatalf("status=%d body=%s", rec.Code, rec.Body.String())
+	}
+	var body apiError
+	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
+		t.Fatalf("unmarshal response: %v", err)
+	}
+	if body.Reason != reasonValidationFailed {
+		t.Fatalf("reason=%q body=%s", body.Reason, rec.Body.String())
+	}
+	if body.Details["field"] != "content" {
+		t.Fatalf("details=%v", body.Details)
+	}
+}
+
+func TestWriteStoreErrorMapsPolicyToValidationFailed(t *testing.T) {
+	req := httptest.NewRequest(http.MethodPost, "/v1/workbench/executive-mailbox/submissions", nil)
+	rec := httptest.NewRecorder()
+
+	writeStoreError(rec, req, store.ErrPolicy)
+
+	if rec.Code != http.StatusBadRequest {
+		t.Fatalf("status=%d body=%s", rec.Code, rec.Body.String())
+	}
+	var body apiError
+	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
+		t.Fatalf("unmarshal response: %v", err)
+	}
+	if body.Reason != reasonValidationFailed {
+		t.Fatalf("reason=%q body=%s", body.Reason, rec.Body.String())
+	}
+}

internal/httpapi/response.go

@@ -17,6 +17,7 @@ const (
 	reasonForbidden        = "FORBIDDEN"
 	reasonNotFound         = "RESOURCE_NOT_FOUND"
 	reasonConflict         = "CONFLICT"
+	reasonValidationFailed = "VALIDATION_FAILED"
 	reasonInternal         = "INTERNAL"
 )
 
@@ -57,6 +58,8 @@ func writeStoreError(w http.ResponseWriter, r *http.Request, err error) {
 		writeError(w, r, http.StatusForbidden, 30041, reasonForbidden, "forbidden", nil)
 	case errors.Is(err, ErrConflict), errors.Is(err, store.ErrConflict):
 		writeError(w, r, http.StatusConflict, 30040, reasonConflict, "conflict", nil)
+	case errors.Is(err, store.ErrPolicy):
+		writeError(w, r, http.StatusBadRequest, 30000, reasonValidationFailed, "validation failed", nil)
 	default:
 		writeError(w, r, http.StatusInternalServerError, 90000, reasonInternal, "internal error", nil)
 	}

internal/store/errors.go

@@ -6,4 +6,5 @@ var (
 	ErrNotFound  = errors.New("resource not found")
 	ErrForbidden = errors.New("forbidden")
 	ErrConflict  = errors.New("conflict")
+	ErrPolicy    = errors.New("policy violation")
 )

internal/store/mysql.go

@@ -719,8 +719,24 @@ func (s *Store) MailboxConfig(ctx context.Context) (*MailboxConfig, error) {
 }
 
 func (s *Store) CreateMailboxSubmission(ctx context.Context, userID int64, submission MailboxSubmission, idempotencyKey string) (*MailboxSubmission, error) {
+	cfg, err := s.MailboxConfig(ctx)
+	if err != nil {
+		return nil, err
+	}
+	submission.Subject = strings.TrimSpace(submission.Subject)
+	submission.Content = strings.TrimSpace(submission.Content)
+	if !cfg.Enabled || (submission.Anonymous && !cfg.AllowAnonymous) {
+		return nil, ErrPolicy
+	}
+	maxLength := cfg.MaxLength
+	if maxLength <= 0 {
+		maxLength = 5000
+	}
+	if len([]rune(submission.Subject)) > 200 || len([]rune(submission.Content)) > maxLength {
+		return nil, ErrPolicy
+	}
 	now := time.Now().UTC().Round(time.Millisecond)
-	_, err := s.db.ExecContext(ctx, `INSERT INTO im_mailbox_submissions(submission_id,sender_id,subject,content,anonymous,attachment_file_ids,notice_version,idempotency_key,status,submitted_at)
+	_, err = s.db.ExecContext(ctx, `INSERT INTO im_mailbox_submissions(submission_id,sender_id,subject,content,anonymous,attachment_file_ids,notice_version,idempotency_key,status,submitted_at)
 		VALUES(?,?,?,?,?,?,?,?,?,?)`, submission.SubmissionID, userID, submission.Subject, submission.Content, submission.Anonymous, submission.AttachmentFileIDs, submission.NoticeVersion, idempotencyKey, "received", now)
 	if isDuplicate(err) && idempotencyKey != "" {
 		var existing MailboxSubmission