refactoring: many occurences of "date" and "time" wrt field names. We…

… just use "dt". Add global variable IN_CAPS for price/dt column names to avoid confusion.

coincharts/daemonize.py

@@ -18,6 +18,7 @@
 import daemon.pidfile
 
 from coincharts import config, db
+from coincharts.models import THE_DATETIME_FIELD, THE_PRICE_FIELD
 
 # We're replacing the module with a dict. Importing the file shouldn't result in reading from disk, etc. That's why.
 config = config.get_config()
@@ -114,7 +115,7 @@ def fetch(self, symbol):
             response.headers['X-RateLimit-Remaining']))
         data = response.json()
         # validate the FIRST date from the data returned. Not perfect, but will prevent future heartache.
-        self.validate_datetime_object(data[0]['time_period_start'])  # TODO. how to track that we want *this* time field
+        self.validate_datetime_object(data[0][THE_DATETIME_FIELD])
         return data
 
     def get_last_date_from_store(self, symbol):
@@ -123,7 +124,7 @@ def get_last_date_from_store(self, symbol):
         except db.Prices.DoesNotExist:
             logging.info('No `time_period_end` value found for {}'.format(symbol))
             return None
-        dt = getattr(obj, 'time')
+        dt = getattr(obj, 'dt')
         return parse_dt(dt)
 
     def insert(self, symbol, data):

coincharts/data.py

@@ -25,9 +25,9 @@ def normalized_price_history(self):
 
     @property
     @memoize
-    def date_range(self):
-        start = self.history[0].time
-        end = self.history[len(self.history)-1].time
+    def dt_range(self):
+        start = self.history[0].dt
+        end = self.history[len(self.history)-1].dt
         return start, end
 
     @property
@@ -59,20 +59,20 @@ def __init__(self, *args, **kwargs):
 
     @property
     @memoize
-    def start_date_indexes(self):
+    def start_dt_indexes(self):
         indexes = {}
         for symbol, data in self.items():
             try:
-                indexes[symbol] = [s.time for s in data.history].index(self.earliest_common_time)
+                indexes[symbol] = [s.dt for s in data.history].index(self.earliest_common_dt)
             except ValueError:
-                raise ValueError('Could not find date {} in history of {}'.format(
-                    self.earliest_common_time, symbol))
+                raise ValueError('Could not find datetime {} in history of {}'.format(
+                    self.earliest_common_dt, symbol))
         return indexes
 
     @property
     @memoize
-    def earliest_common_time(self):
-        return sorted([symbol.history[0].time for symbol in self.values()])[0]
+    def earliest_common_dt(self):
+        return sorted([symbol.history[0].dt for symbol in self.values()])[0]
 
     def normalized_price_history_averages(self):
         normalized_price_history_generators = []
@@ -102,7 +102,7 @@ def normalized_price_history_averages(self):
     #     print(name,
     #           info.min,
     #           info.max, '\t',
-    #           info.date_range, sep='\t')
+    #           info.dt_range, sep='\t')
 
     comparison = SymbolComparison(symbol_info)
 

coincharts/models.py

@@ -1,6 +1,10 @@
 
 from django.db import models
 
+# There are many datetime/price fields. We are interested almost exclusively in these two, and they are used in many places.
+# Less headache if we use these ugly global names to avoid confusion 
+THE_DATETIME_FIELD = 'time_period_end'
+THE_PRICE_FIELD = 'price_close'
 
 class Prices(models.Model):
 
@@ -21,25 +25,25 @@ class Prices(models.Model):
 
     @property
     def price(self):
-        return self.price_close
+        return getattr(self, THE_PRICE_FIELD)
 
     @price.setter
     def price(self, value):
-        self.price_close = value
+        setattr(self, THE_PRICE_FIELD, value)
 
     @property
-    def time(self):
-        return self.time_period_end
+    def dt(self):
+        return getattr(self, THE_DATETIME_FIELD)
 
-    @time.setter
-    def time(self, value):
-        self.time_period_start = value
+    @dt.setter
+    def dt(self, value):
+        setattr(self, THE_DATETIME_FIELD, value)
 
     def __str__(self):
         class_name = self.__class__.__name__
         return '{}@{}'.format(
-            self.time_period_end,
-            self.price_close
+            self.dt,
+            self.price
         )
 
     class Meta:

coincharts/views.py

@@ -18,13 +18,13 @@ def string_to_epoch(string):
     def prices_gen(prices):
         x = []
         for p in prices:
-            x.append((p.time, int(p.price)))
+            x.append((p.dt, int(p.price)))
         return x
 
     title = '{} from {} to {}'.format(
         symbol,
-        prices[0].time,
-        prices[len(prices)-1].time,  # "negative indexing is not supported"
+        prices[0].dt,
+        prices[len(prices)-1].dt,  # "negative indexing is not supported"
     )
 
     graph = svg_graph.LineGraph(