Merge branch 'mai/knuth/phase-5c-itemwrite' (phase 5c slice B: web write paths validate)

web/bulk.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/jackc/pgx/v5"
 
+	"github.com/m/projax/internal/itemwrite"
 	"github.com/m/projax/store"
 )
 
@@ -208,6 +209,16 @@ func (s *Server) handleBulkApply(w http.ResponseWriter, r *http.Request) {
 	case action.describe() == "":
 		banner = "No action chosen — type a tag, pick a management mode, or pick a status before clicking Apply."
 	default:
+		// Pre-flight bulk action via itemwrite where applicable. set_status
+		// is the only bulk action today that mutates a validated field
+		// (status enum); the others (add_tag / set_mgmt / set_public /
+		// timeline_todos) operate outside the validator's rule set.
+		if action.SetStatus != "" {
+			if ve := itemwrite.ValidateFormat(itemwrite.Input{Title: "x", Slug: "x", Status: action.SetStatus}); ve != nil {
+				banner = "Cannot apply: " + itemWriteBannerCopy(ve)
+				break
+			}
+		}
 		if err := s.applyBulk(r.Context(), ids, action); err != nil {
 			s.fail(w, r, err)
 			return

web/server.go

@@ -16,9 +16,47 @@ import (
 
 	"github.com/m/projax/internal/aggregate"
 	"github.com/m/projax/internal/cache"
+	"github.com/m/projax/internal/itemwrite"
 	"github.com/m/projax/store"
 )
 
+// itemWriteFailure surfaces an *itemwrite.ValidationError to the client.
+// HTTP code: 400 for invalid input. The body is a one-line human banner
+// keyed on Kind so handlers don't have to duplicate copy-table fragments.
+// Phase 5c uses this instead of the pre-existing raw-pgErr-on-failure
+// pattern in handleDetailWrite / handleNewSubmit / handleReparent.
+func (s *Server) itemWriteFailure(w http.ResponseWriter, r *http.Request, ve *itemwrite.ValidationError) {
+	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+	w.WriteHeader(http.StatusBadRequest)
+	fmt.Fprintln(w, itemWriteBannerCopy(ve))
+	s.Logger.Warn("itemwrite reject", "path", r.URL.Path, "kind", ve.Kind, "detail", ve.Detail)
+}
+
+// itemWriteBannerCopy maps a ValidationError.Kind to the human-facing
+// banner copy. Centralised so web/server.go + web/bulk.go share one
+// authoritative phrasing.
+func itemWriteBannerCopy(ve *itemwrite.ValidationError) string {
+	switch ve.Kind {
+	case itemwrite.KindMissingRequired:
+		return "Missing required field: " + ve.Detail
+	case itemwrite.KindInvalidSlugFormat:
+		return ve.Detail
+	case itemwrite.KindInvalidStatus:
+		return ve.Detail
+	case itemwrite.KindSelfParent:
+		return "An item cannot be its own parent."
+	case itemwrite.KindUnknownParent:
+		return ve.Detail
+	case itemwrite.KindSlugCollision:
+		return ve.Detail
+	case itemwrite.KindCycle:
+		return "Cannot reparent: this move would put the item in its own ancestor closure."
+	case itemwrite.KindUnresolvablePath:
+		return ve.Detail
+	}
+	return "Invalid input: " + ve.Detail
+}
+
 // Register MIME types stdlib doesn't ship by default. The web-app manifest
 // spec requires application/manifest+json for the `<link rel=manifest>` →
 // without this Go's FileServer falls back to text/plain and Chrome refuses
@@ -511,12 +549,27 @@ func (s *Server) handleDetailWrite(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 	parentIDs = dedupeStrings(parentIDs)
+	title := strings.TrimSpace(r.FormValue("title"))
+	slug := strings.TrimSpace(r.FormValue("slug"))
+	status := strings.TrimSpace(r.FormValue("status"))
+	if ve := itemwrite.ValidateFormat(itemwrite.Input{
+		ID: it.ID, Title: title, Slug: slug, Status: status, ParentIDs: parentIDs, Path: it.PrimaryPath(),
+	}); ve != nil {
+		s.itemWriteFailure(w, r, ve)
+		return
+	}
+	if ve := itemwrite.ValidateAgainstStore(r.Context(), s.Store, itemwrite.Input{
+		ID: it.ID, Title: title, Slug: slug, Status: status, ParentIDs: parentIDs, Path: it.PrimaryPath(),
+	}); ve != nil {
+		s.itemWriteFailure(w, r, ve)
+		return
+	}
 	in := store.UpdateInput{
-		Title:      strings.TrimSpace(r.FormValue("title")),
-		Slug:       strings.TrimSpace(r.FormValue("slug")),
+		Title:      title,
+		Slug:       slug,
 		ParentIDs:  parentIDs,
 		ContentMD:  r.FormValue("content_md"),
-		Status:     strings.TrimSpace(r.FormValue("status")),
+		Status:     status,
 		Pinned:     r.FormValue("pinned") == "1",
 		Archived:   r.FormValue("archived") == "1",
 		Tags:       parseCSV(r.FormValue("tags")),
@@ -567,6 +620,21 @@ func (s *Server) handleReparent(w http.ResponseWriter, r *http.Request, path str
 		http.Error(w, "reparent: parent_ids required", http.StatusBadRequest)
 		return
 	}
+	// Reparent doesn't change title/slug/status, so the validator only
+	// exercises rules around parent_ids: self-parent, unknown-parent,
+	// cycle. Format check runs against the existing item's fields.
+	if ve := itemwrite.ValidateFormat(itemwrite.Input{
+		ID: it.ID, Title: it.Title, Slug: it.Slug, Status: it.Status, ParentIDs: parentIDs, Path: it.PrimaryPath(),
+	}); ve != nil {
+		s.itemWriteFailure(w, r, ve)
+		return
+	}
+	if ve := itemwrite.ValidateAgainstStore(r.Context(), s.Store, itemwrite.Input{
+		ID: it.ID, Title: it.Title, Slug: it.Slug, Status: it.Status, ParentIDs: parentIDs, Path: it.PrimaryPath(),
+	}); ve != nil {
+		s.itemWriteFailure(w, r, ve)
+		return
+	}
 	moved, err := s.Store.Reparent(r.Context(), it.ID, parentIDs)
 	if err != nil {
 		s.fail(w, r, err)
@@ -700,13 +768,30 @@ func (s *Server) handleNewSubmit(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 	parentIDs = dedupeStrings(parentIDs)
+	title := strings.TrimSpace(r.FormValue("title"))
+	slug := strings.TrimSpace(r.FormValue("slug"))
+	status := strings.TrimSpace(r.FormValue("status"))
+	// New items have no ID yet — pre-flight format checks (title/slug/status)
+	// then DB-aware checks (parent existence + slug collision under parents).
+	if ve := itemwrite.ValidateFormat(itemwrite.Input{
+		Title: title, Slug: slug, Status: status, ParentIDs: parentIDs,
+	}); ve != nil {
+		s.itemWriteFailure(w, r, ve)
+		return
+	}
+	if ve := itemwrite.ValidateAgainstStore(r.Context(), s.Store, itemwrite.Input{
+		Title: title, Slug: slug, Status: status, ParentIDs: parentIDs,
+	}); ve != nil {
+		s.itemWriteFailure(w, r, ve)
+		return
+	}
 	in := store.CreateInput{
 		Kind:       []string{kind},
-		Title:      strings.TrimSpace(r.FormValue("title")),
-		Slug:       strings.TrimSpace(r.FormValue("slug")),
+		Title:      title,
+		Slug:       slug,
 		ParentIDs:  parentIDs,
 		ContentMD:  r.FormValue("content_md"),
-		Status:     strings.TrimSpace(r.FormValue("status")),
+		Status:     status,
 		Tags:       parseCSV(r.FormValue("tags")),
 		Management: parseCSV(r.FormValue("management")),
 	}