✉ :)

db.py

@@ -203,7 +203,6 @@ class DDBTable(object):
         message = yield gen.Task(self._dynamodb(operation='Scan').call,
             TableName=self._get_table_name())
         data = [self.decode_item(item=item) for item in message['Items']]
-
         raise gen.Return(data)
 
 
@@ -339,24 +338,44 @@ class DDBmeasurements(DDBTable):
         data = self.decode_item(item=message['Item'])
         raise gen.Return(data)
 
-if __name__ == '__main__':
-    types = DDBtypes()
-    types.create_table()
-    types.add(1, 2, 3, 4, 5)
-    ioloop = IOLoop.instance()
-    result = ioloop.run_sync(partial(types.get_all))
-    print(result)
-
-    measurements = DDBmeasurements()
-    measurements.create_table()
-    measurements.add(1, 2, 3, 4)
-    ioloop = IOLoop.instance()
-    result = ioloop.run_sync(partial(measurements.get_all))
-    print(result)
-
-    stations = DDBstations()
-    stations.create_table()
-    stations.add(1, 2, 3, 4)
-    ioloop = IOLoop.instance()
-    result = ioloop.run_sync(partial(stations.get_all))
-    print(result)
+
+class DDBlastmeasurements(DDBTable):
+    TABLE_NAME = 'lastmeasurements'
+    KEY_SCHEMA = [{
+        'AttributeName': 'station_id',
+        'KeyType': 'HASH',
+    },
+    {
+        'AttributeName': 'pollution_id',
+        'KeyType': 'HASH',
+    }]
+    PROVISIONED_THROUGHPUT = {
+        'ReadCapacityUnits': 1,
+        'WriteCapacityUnits': 1
+    }
+    FIELDS = {
+        'station_id': DDBUUIDField,
+        'pollution_id': DDBUUIDField,
+        'measurement_id': DDBUUIDField,
+    }
+
+    @gen.coroutine
+    def add(self, measurement):
+        data = {
+            'measurement_id': measurement.id,
+        }
+
+        message = yield gen.Task(self._dynamodb(operation='UpdateItem').call,
+            TableName=self._get_table_name(),
+            Key=self.encode_item(data={'station_id': measurement.station.id, 'pollution_id': measurement.type.id}),
+            AttributeUpdates=self.encode_item(data=data, update=True))
+        raise gen.Return(message)
+
+    @gen.coroutine
+    def get(self, station, pollution_type):
+        message = yield gen.Task(self._dynamodb(operation='GetItem').call,
+            TableName=self._get_table_name(),
+            Key=self.encode_item(data={'station_id': station.id, 'pollution_id': pollution_type.id})
+                                 )
+        data = self.decode_item(item=message['Item'])
+        raise gen.Return(data)
\ No newline at end of file

measurement_viewer.py

@@ -19,10 +19,12 @@ class MainHandler(tornado.web.RequestHandler):
         #stations = models.Station.get_all()
         #stations = models.Station.getall()
         stations = yield models.Station.get_all()
+        pollutions = yield models.Type.get_all()
 
-        measurement = yield models.Measurement.get("5c2be10b-5d33-47d7-95fe-b3f6fc29a3af")
-        for s in stations:
-            self.write("{0} {1} {2} {3} {4}<br />".format(s.id, s.city, s.longitude, s.latitude, s.name))
+        for station in stations.values():
+            for pollution in pollutions.values():
+                measurement = yield models.Measurement.get_last(station, pollution)
+                self.write(str(measurement))
 
         # measurement = models.Measurement.getlast(station=s.id)
         # self.write("".format())

models.py

 import uuid
 
-from db import DDBtypes, DDBmeasurements, DDBstations
+from db import DDBtypes, DDBmeasurements, DDBstations, DDBlastmeasurements
 from functools import partial
 from tornado.gen import coroutine
 
@@ -41,12 +41,14 @@ class Station(DDBobject):
     @classmethod
     @coroutine
     def get_all(cls):
+        if not cls.stored:
             data = yield DDBstations().get_all()
             return_value = []
             for station in data:
                 return_value.append(cls.from_dict(station))
+            cls.stored = {i.id: i for i in return_value}
 
-        return return_value
+        return cls.stored
 
 
 class Type(DDBobject):
@@ -69,10 +71,23 @@ class Type(DDBobject):
         result = yield DDBtypes().get(type_id)
         return cls.from_dict(result)
 
+    @coroutine
     def save(self):
-        result = yield (DDBtypes().add(pollution_type=self))
+        result = yield DDBtypes().add(pollution_type=self)
         return result
 
+    @classmethod
+    @coroutine
+    def get_all(cls):
+        if not cls.stored:
+            data = yield DDBtypes().get_all()
+            return_value = []
+            for pollution_type in data:
+                return_value.append(cls.from_dict(pollution_type))
+            cls.stored = {i.id: i for i in return_value}
+
+        return cls.stored
+
 
 class Measurement(DDBobject):
     stored = {}
@@ -105,9 +120,15 @@ class Measurement(DDBobject):
     @coroutine
     def save(self):
         result = yield DDBmeasurements().add(measurement=self)
+        result = yield DDBlastmeasurements().add(measurement=self)
         return result
 
+    @classmethod
     @coroutine
-    def get_last(self, station_id):
-        # TODO
-        pass
+    def get_last(cls, station, pollution_type):
+        data = yield DDBlastmeasurements().get(station, pollution_type)
+        return_value = yield cls.get(measurement_id=data['measurement_id'])
+        return return_value
+
+    def __str__(self):
+        return "{0} {1} {2} {3} {4}".format(self.id, self.station.id, self.type.id, self.value, self.time)