refac: authenticated user can upload an image to an existing article and receives its public location; an unknown article returns 404 and a disallowed type returns 400

api/handlers/image/imageHandler.go

@@ -1,9 +1,12 @@
 package image
 
 import (
-	"RenewCMS/internal/domain/image"
+	"RenewCMS/api/pkg/apperr"
+	domainArticle "RenewCMS/internal/domain/article"
+	domainImage "RenewCMS/internal/domain/image"
 	"RenewCMS/internal/infrastructure/useCases"
 	"encoding/json"
+	"errors"
 	"net/http"
 	"strconv"
 
@@ -12,21 +15,41 @@ import (
 
 type Handler struct {
 	CreateUseCase *useCases.CreateImageUseCase
+	GetUseCase    *useCases.GetArticleUseCase
 	UpdateUseCase *useCases.UpdateArticleUseCase
 }
 
-func NewHandler(create *useCases.CreateImageUseCase, update *useCases.UpdateArticleUseCase) *Handler {
+func NewHandler(create *useCases.CreateImageUseCase, get *useCases.GetArticleUseCase, update *useCases.UpdateArticleUseCase) *Handler {
 	return &Handler{
 		CreateUseCase: create,
+		GetUseCase:    get,
 		UpdateUseCase: update,
 	}
 }
 
-func (h *Handler) PostImage(w http.ResponseWriter, r *http.Request) {
-	_ = r.ParseForm()
+func writeInternalServerError(w http.ResponseWriter) {
+	http.Error(w, "Internal server error", http.StatusInternalServerError)
+}
 
-	id := chi.URLParam(r, "id")
-	idInt, _ := strconv.Atoi(id)
+func writeArticleError(w http.ResponseWriter, err error) {
+	if errors.Is(err, domainArticle.ErrArticleNotFound) {
+		http.Error(w, apperr.ArticleNotFoundErrorMessage, http.StatusNotFound)
+		return
+	}
+	writeInternalServerError(w)
+}
+
+func (h *Handler) PostImage(w http.ResponseWriter, r *http.Request) {
+	articleId, err := strconv.ParseUint(chi.URLParam(r, "id"), 10, 32)
+	if err != nil {
+		http.Error(w, apperr.IdUint32ErrorMessage, http.StatusBadRequest)
+		return
+	}
+
+	if _, err := h.GetUseCase.GetArticle(uint32(articleId)); err != nil {
+		writeArticleError(w, err)
+		return
+	}
 
 	file, fileHeader, err := r.FormFile("file")
 	if err != nil {
@@ -35,25 +58,32 @@ func (h *Handler) PostImage(w http.ResponseWriter, r *http.Request) {
 	}
 	defer file.Close()
 
-	newImage, err := h.CreateUseCase.CreateImage(image.ImageInput{
+	newImage, err := h.CreateUseCase.CreateImage(domainImage.ImageInput{
 		Content:     file,
 		Filename:    fileHeader.Filename,
 		Size:        fileHeader.Size,
 		ContentType: fileHeader.Header.Get("Content-Type"),
 	})
 	if err != nil {
-		http.Error(w, err.Error(), http.StatusInternalServerError)
+		if errors.Is(err, domainImage.ErrImageTypeNotAllowed) || errors.Is(err, domainImage.ErrImageTooLarge) {
+			http.Error(w, err.Error(), http.StatusBadRequest)
+			return
+		}
+		writeInternalServerError(w)
 		return
 	}
 
-	err = h.UpdateUseCase.AddImage(uint32(idInt), newImage.ID)
+	if err := h.UpdateUseCase.AddImage(uint32(articleId), newImage.ID); err != nil {
+		writeArticleError(w, err)
+		return
+	}
+
+	responseJson, err := json.Marshal(map[string]any{"location": newImage.Path})
 	if err != nil {
-		http.Error(w, err.Error(), http.StatusInternalServerError)
+		writeInternalServerError(w)
 		return
 	}
 
-	newJson := map[string]any{"location": newImage.Path}
-	newJsonBytes, _ := json.Marshal(newJson)
-
-	_, _ = w.Write(newJsonBytes)
+	w.WriteHeader(http.StatusCreated)
+	_, _ = w.Write(responseJson)
 }