At the point where it has:

• A field for submitting a URL with a submit button
• The server can fetch the XML file and return it (or an error) to the client as JSON
• The client can display errors it gets from the server
• The client can support creating a new blank feed form to fill out
• Given a feed json from the server, the client can parse the JSON and display:
• • All the top-level category attributes (channelAttributes component), each as an editableLine
• • All the items in the feed, each with its own list of editableLines for its attributes
• the form is composed of editableLine components that allow:
• • displaying the current value of the line
• • toggling into an edit mode with a free-text field for arbitrary text entry
• • saving that text entry to the global state for that line
• Ability to add a new item to an existing feed
• Ability to send JSON-encoded feed data to the server and have the server return an encoded xml file
• Ability to download the returned XML as a file