Fix product images

app/controllers/suppliers/products_controller.rb

@@ -68,10 +68,10 @@ module Suppliers
       respond_to do |format|
         if @product.update_attributes(product_params)
           format.html { redirect_to [:suppliers, :products], notice: t('action.update.successfull', model: Product.model_name.human) }
-          format.json { render json: @product }
+          format.json { render json_response @product }
         else
           format.html { render action: "edit" }
-          format.json { render json: {errors: @product.errors}, status: :unprocessable_entity }
+          format.json { render json_response @product }
         end
       end
     end
@@ -96,11 +96,34 @@ module Suppliers
     def product_params
       permitted_attributes = [:name, :code, :price, :description, :image, :visible, :position, :active, :product_category_id]
       # do not raise in development and test for json communication
-      if request.format.json?
+      result = if request.format.json?
         params.require(:product).slice(*permitted_attributes).permit!
       else
         params.require(:product).permit permitted_attributes
       end
+      decode_base64_params result, :image
+    end
+
+    BASE64_IMAGE_MATCHER = /^data:image\/(\w+);base64,/ # data:image/png;base64,
+    # inspired by: https://stackoverflow.com/questions/32984963/upload-base64-encoded-image-with-paperclip-rails
+    def decode_base64_params(authorized_params, attributes = [])
+      tempfiles = []
+      attributes = Array.wrap(attributes) # allow single attribute argument without array notation
+      attributes.each do |attribute|
+        if value = authorized_params[attribute].presence
+          if value.is_a?(String) and match = value.match(BASE64_IMAGE_MATCHER)
+            image_type = match[1]
+            decoded_attribute = Base64.decode64 value.sub BASE64_IMAGE_MATCHER, ''
+            file = Tempfile.new(['image', ".#{image_type}"])
+            file.binmode
+            file.write decoded_attribute
+            authorized_params[attribute] = file
+          end
+        end
+      end
+      authorized_params
+    ensure
+      tempfiles.each &:unlink
     end
   end
 end