Refactoring and new experimental behavior

=========================================

* Our `/daemon` package renamed `daemonize.py`. easiest way to resolve conflict with `daemon` package.
* `logger.py`: centralize logging logic.
* `data.py` module containing new logic

coincharts/daemon/base.py → coincharts/daemonize.py

@@ -17,13 +17,13 @@
 import daemon
 import daemon.pidfile
 
-from coincharts import config, db
+from coincharts.daemon import db
+from coincharts import config
 
 # 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()
 
-logger = logging.getLogger(__name__)
-logger.setLevel(logging.DEBUG)
+from coincharts import logger
 
 ch = logging.StreamHandler()
 ch.setLevel(logging.DEBUG)

coincharts/data.py

@@ -0,0 +1,89 @@
+# -*- mode: python; coding: utf-8 -*-
+
+import os
+os.environ['DJANGO_SETTINGS_MODULE'] = 'coincharts.settings'
+
+from mutils.memoize import memoize
+
+from coincharts.db import *
+
+from coincharts import config
+config = config.get_config()
+
+symbol_ids = config['history_symbols']
+
+class SymbolIdInfo(object):
+
+    def __init__(self, symbol_id):
+        self.symbol_id = symbol_id
+
+    def normalize_price(self, price):
+        return (price - self.min) / (self.max - self.min)
+
+    @property
+    @memoize
+    def date_range(self):
+        start = self.history[0].time
+        end = self.history[len(self.history)-1].time
+        return start, end
+
+    @property
+    @memoize
+    def min(self):
+        return min([s.price for s in self.history])
+
+    @property
+    @memoize
+    def max(self):
+        return max([s.price for s in self.history])
+
+    @property
+    @memoize
+    def history(self):
+        return Prices.objects.filter(symbol_id=self.symbol_id)
+
+    @property
+    def normalized_price_history(self):
+        price_delta = self.max - self.min
+        for price in self.history:
+            yield (price - self.min) / price_delta
+
+
+class SymbolIdComparison(dict):
+
+    def __init__(self, *args, **kwargs):
+        self.update(*args, **kwargs)
+        self._start_date_indexes = {}
+        self._earliest_common_time = None
+
+    @property
+    def start_date_indexes(self):
+        if self._start_date_indexes is not None:
+            return self._start_date_indexes
+        for symbol_id, data in self.items():
+            try:
+                self._start_date_indexes[symbol_id] = \
+                    [s.date for s in data].index(self.earliest_common_time)
+            except ValueError:
+                raise ValueError('Could not find date {} in history of {}'.format(
+                    self.earliest_common_time, symbol_id))
+
+    @property
+    def earliest_common_time(self):
+        if self._earliest_common_time is not None:
+            return self._earliest_common_time
+        self._earliest_common_time = sorted([symbol[0].date for symbol in self.values()])[0]
+        return self._earliest_common_time
+
+if __name__ == '__main__':
+
+    symbol_id_info = SymbolIdComparison()
+    for symbol_id in symbol_ids:
+        symbol_id_info[symbol_id] = SymbolIdInfo(symbol_id)
+
+    print('name\t\t\tmin\tmax\t\t\trange')
+    for name, info in symbol_id_info.items():
+        print(name,
+              info.min,
+              info.max, '\t',
+              info.date_range, sep='\t')

coincharts/db.py

@@ -1,19 +1,48 @@
 # -*- mode: python; coding: utf-8 -*-
-"""re-export `modules.*` and make models (and ORM) usable outside of web framework.
+"""re-export `models.*` and make models (and ORM) usable outside of web framework.
 
-So, if you have django "app" `foo` installed as a package, from anywhere you should be able to
-
->>> record = foo.db.SomeTable(**kwargs)
+>>> import db
+>>> record = db.SomeTable(**kwargs)
 >>> record.save()
 
 et cetera.
 """
 
+import os
+import importlib
 import django
-from .settings import *
+
+from coincharts import logger
+
+# There is a bit of hackery here. Read comments starting with 'HACK'
+
+try:
+    # HACK -- we require that DJANGO_SETTINGS_MODULE be set to the the name
+    # of the site's settings' module, e.g. `mysite.settings`
+    django_settings_module_name = os.environ['DJANGO_SETTINGS_MODULE']
+except KeyError:
+    raise ImportError("""
+The "DJANGO_SETTINGS_MODULE" environment must be set to the name of your site's setting's module. For example:
+
+    export DJANGO_SETTINGS_MODULE="mysite.settings"
+""")
+
+# HACK -- this is magic for "from mysite.settings import *"
+globals().update(importlib.import_module(
+    django_settings_module_name).__dict__)
+
 from django.conf import settings
+from django.db import connections
+import atexit
 
+# HACK -- note that the rhs "DATABASES" here comes from mysite.settings, above
 settings.configure(DATABASES=DATABASES)
 django.setup()
 
-from .models import *
+from coincharts.models import *
+
+def cleanup():
+    logger.info('closing all django database connections for this process')
+    connections.close_all()
+
+atexit.register(cleanup)

coincharts/logger.py

@@ -0,0 +1,15 @@
+# -*- mode: python; coding: utf-8 -*-
+"""A small amount of justified magic: with this module,
+
+>>> import logger
+>>> logger.debug('yay!')
+"""
+
+import logging
+
+_logger = logging.getLogger(__name__)
+_logger.setLevel(logging.DEBUG)
+
+for level in 'debug', 'info', 'warning', 'error', 'exception', 'critical', 'addHandler':
+    globals()[level] = getattr(_logger, level)
+

coincharts/models.py

@@ -4,7 +4,7 @@
 
 class Prices(models.Model):
 
-    symbol_id = models.CharField(max_length=100)
+    symbol_id = models.CharField(db_index=True, max_length=100)
     time_period_start = models.CharField(max_length=100)
     time_period_end = models.CharField(max_length=100)
     time_open = models.CharField(max_length=100)