Create a simple restful API mounted at /v1/

Add a list of resources we can serve.
Update themes page to list our resources.

app.py

@@ -1,6 +1,9 @@
 from flask import Flask
-from flask import render_template
+from flask import abort, render_template
+from flask_restful import Resource, Api, abort as api_abort
+
 app = Flask(__name__)
+api = Api(app)
 
 @app.route('/')
 def welcome():
@@ -10,13 +13,34 @@ def welcome():
 def about():
     return render_template('about.html')
 
+THEMES = {
+    '1': {'theme_id': '1'},
+    'a': {'theme_id': 'a'},
+}
+
+class ThemeList(Resource):
+    def get(self):
+        return THEMES
+
+class Theme(Resource):
+    def get(self, theme_id):
+        if theme_id not in THEMES:
+            api_abort(404, message="Theme {} not found".format(theme_id))
+
+        return THEMES[theme_id]
+
 @app.route('/themes/')
 @app.route('/themes/<theme_id>')
 def themes(theme_id=None):
     if theme_id:
+        if theme_id not in THEMES:
+            abort(404)
         return render_template('theme.html', theme_id=theme_id)
     else:
-        return render_template('themes.html')
+        return render_template('themes.html', themes=THEMES)
+
+api.add_resource(ThemeList, '/v1/themes/')
+api.add_resource(Theme, '/v1/themes/<string:theme_id>')
 
 if __name__ == '__main__':
     app.run(debug=True)

templates/themes.html

@@ -2,3 +2,10 @@
 {% block title %}Themes{% endblock %}
 {% block heading %}Themes{% endblock %}
 
+{% block content %}
+<ul>
+{% for theme_id in themes %}
+  <li><a href="{{ theme_id }}">theme {{ themes[theme_id].theme_id }}</a></li>
+{% endfor %}
+</ul>
+{% endblock %}