Better server: filters, encoder, page overlap, and more

mds/fake/server.py

@@ -1,6 +1,19 @@
 
 from flask import Flask, request, jsonify, url_for
+import mds.json
 import json, base64
+from datetime import datetime
+import pytz
+
+epoch = pytz.utc.localize(datetime(1970, 1, 1, 0, 0, 0))
+
+def ensure_unixtime(dt_or_float):
+    if isinstance(dt_or_float, datetime):
+        return (dt_or_float - epoch).total_seconds()
+    return dt_or_float
+
+class UnixtimeJSONEncoder(mds.json.CustomJsonEncoder):
+    date_format = 'unix'
 
 class PaginationCursor(object):
     def __init__(self, serialized_cursor=None, offset=None):
@@ -17,14 +30,15 @@ def serialize(self):
         return base64.b64encode(json.dumps({ 'o': self.offset }).encode('utf-8'))
 
 class InMemoryPaginator(object):
-    def __init__(self, all_items, serialized_cursor=None, page_size=20):
+    def __init__(self, all_items, serialized_cursor=None, page_size=20, next_page_shortness=0):
         self.items = all_items
         self.cursor = PaginationCursor(serialized_cursor)
         self.page_size = page_size
+        self.next_page_shortness = next_page_shortness
 
     def next_cursor_serialized(self):
         offset = self.cursor.offset
-        return PaginationCursor(offset=offset+self.page_size).serialize()
+        return PaginationCursor(offset=offset+self.page_size-self.next_page_shortness).serialize()
 
     def get_page(self):
         offset = self.cursor.offset
@@ -49,40 +63,76 @@ def params_match_trip(params, trip):
     if vehicle_id and trip['vehicle_id'] != vehicle_id:
         return False
 
+    device_id = params.get('device_id')
+    if device_id and trip['device_id'] != device_id:
+        return False
+
+    start_time = params.get('start_time')
+    if start_time and ensure_unixtime(trip['start_time']) < float(start_time):
+        return False
+
+    end_time = params.get('end_time')
+    if end_time and ensure_unixtime(trip['end_time']) > float(end_time):
+        return False
+
+    bbox = params.get('bbox')
+    if bbox is not None:
+        raise NotImplementedError('fake server does not support bbox queries')
+
     return True
 
 def params_match_status_change(params, sc):
+    start_time = params.get('start_time')
+    if start_time and ensure_unixtime(sc['event_time']) < float(start_time):
+        return False
+
+    end_time = params.get('end_time')
+    if end_time and ensure_unixtime(sc['event_time']) > float(end_time):
+        return False
+
+    bbox = params.get('bbox')
+    if bbox is not None:
+        raise NotImplementedError('fake server does not support bbox queries')
+
     return True
 
 def make_static_server_app(trips=[],
                            status_changes=[],
                            version='0.2.0',
-                           page_size=20):
+                           page_size=20,
+                           next_page_shortness=0):
     app = Flask('mds_static')
+
+    options = {
+        'next_page_shortness': next_page_shortness,
+        'page_size': page_size,
+    }
+
     store = {
         'trips': trips,
         'status_changes': status_changes,
     }
+    app.config['STATIC_MDS_DATA'] = store
+    app.config['STATIC_MDS_OPTIONS'] = options
+    app.json_encoder = UnixtimeJSONEncoder
 
     @app.route('/trips')
     def trips():
-        params = {
-            'vehicle_id': request.args.get('vehicle_id'),
-            # TODO: support other params
-        }
+        supported_param_keys =  ('device_id', 'vehicle_id', 'start_time', 'end_time', 'bbox')
+        params = { k: request.args.get(k) for k in request.args if k in supported_param_keys}
         selected_trips = [t for t in store['trips'] if params_match_trip(params, t)]
         paginator = InMemoryPaginator(selected_trips,
                                       serialized_cursor=request.args.get('cursor'),
-                                      page_size=page_size)
+                                      page_size=page_size,
+                                      next_page_shortness=next_page_shortness)
         return jsonify(make_mds_response_data(
             version, 'trips', paginator, **params
         ))
 
     @app.route('/status_changes')
     def status_changes():
-        params = {
-            # TODO
-        }
+        supported_param_keys = ('start_time', 'end_time', 'bbox')
+        params = { k: request.args.get(k) for k in request.args if k in supported_param_keys}
         selected_items = [sc for sc in store['status_changes'] if params_match_status_change(params, sc)]
         paginator = InMemoryPaginator(selected_items,
                                       serialized_cursor=request.args.get('cursor'),