Map data refs to api links

api/__init__.py

@@ -18,7 +18,10 @@
 """
 
 import json
-from werkzeug.wrappers import Response
+from functools import wraps
+from collections import defaultdict
+from werkzeug.routing import Map, Rule
+from werkzeug.wrappers import Request, Response
 from werkzeug.wsgi import DispatcherMiddleware
 
 # The config imports should come before other package modules so other moudles can import it
@@ -28,20 +31,82 @@
 from api import repo
 
 
-dispatch_appmap = {
-    '/courses': data.Resource(provider_class=data.Course),
-    '/subjects': data.Resource(provider_class=data.Subject),
-    '/instructors': data.Resource(provider_class=data.Instructor),
-}
+url_map = Map()
+endpoint_provider_map = {}
 
+urls = url_map.bind('localhost')
 
-def root_app(environ, start_response):
-    resources = {"resources": list(dispatch_appmap.keys())}
-    response = Response(json.dumps(resources), mimetype='application/json')
+
+def route(path, methods=None):
+    """Register a function to be called for an endpoint.
+
+    The function's return data will be jsonified and used as the response.
+    """
+    methods = methods or ['GET']
+
+    def endpoint_wrapper(func):
+        @wraps(func)
+        def endpoint_func(*args, **kwargs):
+            return func(*args, **kwargs)
+        endpoint_provider_map[func.__name__] = endpoint_func
+        rule = Rule(path, methods=methods, endpoint=func.__name__)
+        url_map.add(rule)
+        return endpoint_func
+    return endpoint_wrapper
+
+
+def route_resource(url_root, provider, endpoint):
+    """Register a resource to be served over the API"""
+    endpoint_provider_map[endpoint] = provider
+    for resource_method, http_method, sub_url in provider.routed_methods:
+        url = url_root + sub_url
+        methods = [http_method]
+        endpoint_str = '.'.join((endpoint, resource_method))
+        rule = Rule(url, methods=methods, endpoint=endpoint_str)
+        url_map.add(rule)
+
+
+def api_app(environ, start_response):
+    """WSGI application mapping requests to endpoints"""
+    adapter = url_map.bind_to_environ(environ)
+    handler, values = adapter.match()
+    request = Request(environ)
+    if '.' in handler:  # must be a resource. this is sketch.
+        provider_name, method = handler.split('.', 1)
+        provider = endpoint_provider_map[provider_name]
+        provided_data = getattr(provider, method)(request, **values)
+    else:
+        provider = endpoint_provider_map[handler]
+        provided_data = provider(**values)
+    response = Response(data.dumps(provided_data), mimetype='application/json')
     return response(environ, start_response)
 
-app = DispatcherMiddleware(root_app, dispatch_appmap)
-app = middleware.FieldLimiter(app)
-app = middleware.JsonifyHttpException(app)
-#app = middleware.DataTransformer(app)
-app = middleware.PrettyJSON(app)
+
+@route('/')
+def root():
+    """Provide links to all available resources"""
+    url_methods = defaultdict(set)
+    for resource in url_map.iter_rules():
+        url_methods[str(resource)].update(resource.methods)
+    resources = [{'endpoint': k, 'methods': list(v)} for k, v in sorted(url_methods.items())]
+    return resources
+
+
+# register the resources set up in data
+route_resource('/courses', provider=data.course, endpoint='courses')
+route_resource('/subjects', provider=data.subject, endpoint='subjects')
+route_resource('/instructors', provider=data.instructor, endpoint='instructors')
+
+
+def get_app():
+    """Returns an initialized and middleware-wrapped wsgi application, ready to go"""
+
+    data.Resource.init()
+
+    app = api_app
+    app = middleware.FieldLimiter(app)
+    app = middleware.AbsoluteLinks(app)
+    app = middleware.JsonifyHttpException(app)
+    app = middleware.DataTransformer(app)
+
+    return app