Adding new errors and centralising handling

internal/repository/errors.go

@@ -0,0 +1,35 @@
+package repository
+
+import (
+	"fmt"
+
+	"git.hrafn.xyz/aether/notes/internal/models"
+)
+
+type EmptyContent struct {}
+type EmptyTitle struct {}
+type NoOP struct {}
+type EmptyUpdate struct{}
+type TitleOverflow struct {
+	length int
+}
+
+func (e *EmptyContent) Error() string {
+	return "content cannot be empty"
+}
+
+func (e *EmptyTitle) Error() string {
+	return "title cannot be empty"
+}
+
+func (e *NoOP) Error() string {
+	return "no operation required"
+}
+
+func (e *EmptyUpdate) Error() string {
+	return "update cannot be empty"
+}
+
+func (e *TitleOverflow) Error() string {
+	return fmt.Sprintf("title max length %d, %d provided", models.NoteTitleMaxLength, e.length)
+}

internal/repository/notes.go

@@ -2,7 +2,6 @@ package repository
 
 import (
 	"context"
-	"fmt"
 	"time"
 
 	"git.hrafn.xyz/aether/notes/internal/models"
@@ -25,13 +24,14 @@ func NewNoteRepository(store NoteStore) *NoteRepository {
 
 // CreateNote creates a new note with the given content.
 func (r *NoteRepository) CreateNote(ctx context.Context, title string, content string) (models.Note, error) {
-	if content == "" {
-		return models.Note{}, fmt.Errorf("content cannot be empty")
-	}
 	note := models.Note{
+		Title:      title,
 		Content:    content,
 		LastUpdate: time.Now(),
 	}
+	if err := isNoteVaid(note); err != nil {
+		return models.Note{}, err
+	}
 	return r.store.SaveNote(ctx, note)
 }
 
@@ -46,15 +46,30 @@ func (r *NoteRepository) ListNotes(ctx context.Context) ([]models.Note, error) {
 }
 
 // UpdateNote updates the content of an existing note.
-func (r *NoteRepository) UpdateNote(ctx context.Context, id int, content string) (models.Note, error) {
-	if content == "" {
-		return models.Note{}, fmt.Errorf("content cannot be empty")
+func (r *NoteRepository) UpdateNote(ctx context.Context, id int, update NoteUpdate) (models.Note, error) {
+	if update.Content == "" && update.Title == "" {
+		return models.Note{}, &EmptyUpdate{}
 	}
 	note, err := r.store.GetNoteByID(ctx, id)
 	if err != nil {
 		return models.Note{}, err
 	}
-	note.Content = content
+
+	if update.Content == note.Content && update.Title == note.Title {
+		return models.Note{}, &NoOP{}
+	}
+
+	if update.Content != "" {
+		note.Content = update.Content
+	}
+	if update.Title != "" {
+		note.Title = update.Title
+	}
+	
+	if err := isNoteVaid(note); err != nil {
+		return models.Note{}, err
+	}
+
 	note.LastUpdate = time.Now()
 	return r.store.SaveNote(ctx, note)
 }
@@ -63,3 +78,20 @@ func (r *NoteRepository) UpdateNote(ctx context.Context, id int, content string)
 func (r *NoteRepository) DeleteNote(ctx context.Context, id int) error {
 	return r.store.DeleteNoteByID(ctx, id)
 }
+
+
+func isNoteVaid(note models.Note) error {
+	if note.Title == "" {
+		return &EmptyTitle{}
+	}
+	if note.Content == "" {
+		return &EmptyContent{}
+	}
+	if titleLen := len(note.Title); titleLen > models.NoteTitleMaxLength {
+		return &TitleOverflow{
+			length: titleLen,
+		}
+	}
+
+	return nil
+}

server/server.go

@@ -85,7 +85,7 @@ func (s *Server) getNotes(w http.ResponseWriter, r *http.Request) {
 func (s *Server) createNote(w http.ResponseWriter, r *http.Request) {
 	note := struct {
 		Content string `json:"content"`
-		Title string `json:"title"`
+		Title   string `json:"title"`
 	}{}
 	if err := json.NewDecoder(r.Body).Decode(&note); err != nil {
 		http.Error(w, "invalid request body", http.StatusBadRequest)
@@ -123,7 +123,7 @@ func (s *Server) updateNoteByID(w http.ResponseWriter, r *http.Request) {
 	}
 	note := struct {
 		Content string `json:"content"`
-		Title string `json:"title"`
+		Title   string `json:"title"`
 	}{}
 	if err := json.NewDecoder(r.Body).Decode(&note); err != nil {
 		http.Error(w, "invalid request body", http.StatusBadRequest)