User-friendly 404-page added

app/controllers/packages_controller.rb

@@ -11,7 +11,12 @@ class PackagesController < ApplicationController
   end
 
   def details
-    @package = Package.find_by!(name: params[:name])
+    @package = Package.find_by(name: params[:name])
+
+    unless @package
+      @packagename = params[:name]
+      render 'notfound'
+    end
   end
 
   def upload

app/views/packages/notfound.slim

@@ -0,0 +1,22 @@
+.row
+
+  h1
+    i.fi-alert
+    '  No such package…
+
+  p
+    ' I'm afraid but there is no package
+    em =@package_name
+    ' in the database. It may be that a package that is available
+    ' in your favorite Linux distribution is not listed here.
+    ' If you think this is an error then feel free to leave
+    a href="mailto:email@christoph-haas.de" feedback
+
+  p
+    ' Perhaps you want to search for some other piece of software?
+    = form_tag(packages_grid_path, method: 'GET')
+      div.row.collapse.postfix-round
+        div.small-9.columns
+          input type="text" name="search"autofocus="true"
+        div.small-3.columns
+          input.button.postfix type="submit" value="Search"