Add some basic client side validation for RSS URL input. Needs to be …

…augmented with some server-side stuff too (later).

app/views/feeds/new.html.erb

@@ -1,5 +1,19 @@
+<%= javascript_include_tag 'validation' %>
+
 <h1>New feed</h1>
 
+<script type="text/javascript">
+function verifyFeedURL(s) {
+  alert(s );
+  if (! isUrl(s) ) {
+    alert('Feed URL is invalid.');
+    return false;
+  }
+  else
+    return true;
+}
+</script>
+
 <% form_for(@feed) do |f| %>
   <%= f.error_messages %>
 
@@ -12,8 +26,8 @@
     <%= f.text_field :interval %>
   </p>
   <p>
-    <%= f.submit 'Create' %>
+    <%= f.submit 'Create', :onClick => 'return verifyFeedURL( feed_url.value );' %>
   </p>
 <% end %>
 
-<%= link_to 'Back', feeds_path %>
+<%= link_to 'Back', feeds_path %>

public/javascripts/validation.js

@@ -0,0 +1,5 @@
+function isUrl(s) {
+	var regexp = /(ftp|http|https):\/\/(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?/
+	return regexp.test(s);
+}
+