only allow pictures for upload

app/models/picture.rb

@@ -5,5 +5,6 @@ class Picture < ApplicationRecord
 
   validates :text, length: { maximum: 80 }
   validates :happened, presence: true
+  validates :picture, presence: true
 
 end

app/models/story.rb

@@ -5,6 +5,7 @@ class Story < ApplicationRecord
 
   validates :text, length: { minimum: 5 , maximum: 1000 }
   validates :header , length: { minimum: 5 , maximum: 400}
+  validates :picture, presence: true
 
   def name
     header

app/uploaders/picture_uploader.rb

@@ -31,11 +31,9 @@ class PictureUploader < CarrierWave::Uploader::Base
   #   process resize_to_fit: [50, 50]
   # end
 
-  # Add an allowlist of extensions which are allowed to be uploaded.
-  # For images you might use something like this:
-  # def extension_allowlist
-  #   %w(jpg jpeg gif png)
-  # end
+  def content_type_allowlist
+    /image\//
+  end
 
   # Override the filename of the uploaded files:
   # Avoid using model.id or version_name here, see uploader/store.rb for details.