enable timerotateloghandler (configurable) (#311)

* attempt to enchance logging

* clean up logging

* clean up logging

* reset to logger

* clean up imports

* add comments in config.py

* remove redundant declaration of logging.config. Already exists in caravel/__init__.py

* replace RotatingFileHandler with TimedRotatingFileHandler

* revert back running web server in debug mode

* fix debug in bin/caravel

* resolve build errors - formatting

* need to test

* enable time rotateloghandler

* revert back print statements - add feature for rotatetimelog which is needed and make it configurable

* revert back to default in master

* fix build issues

* remove extra print statement

* change log location to default

* configure console log level and format

caravel/__init__.py

@@ -6,6 +6,7 @@
 
 import logging
 import os
+from logging.handlers import TimedRotatingFileHandler
 
 from flask import Flask, redirect
 from flask.ext.appbuilder import SQLA, AppBuilder, IndexView
@@ -20,10 +21,6 @@
 APP_DIR = os.path.dirname(__file__)
 CONFIG_MODULE = os.environ.get('CARAVEL_CONFIG', 'caravel.config')
 
-# Logging configuration
-logging.basicConfig(format='%(asctime)s:%(levelname)s:%(name)s:%(message)s')
-logging.getLogger().setLevel(logging.DEBUG)
-
 app = Flask(__name__)
 app.config.from_object(CONFIG_MODULE)
 if not app.debug:
@@ -37,6 +34,18 @@
 
 migrate = Migrate(app, db, directory=APP_DIR + "/migrations")
 
+# Logging configuration
+logging.basicConfig(format=app.config.get('LOG_FORMAT'))
+logging.getLogger().setLevel(app.config.get('LOG_LEVEL'))
+
+if app.config.get('ENABLE_TIME_ROTATE'):
+    logging.getLogger().setLevel(app.config.get('TIME_ROTATE_LOG_LEVEL'))
+    handler = TimedRotatingFileHandler(app.config.get('FILENAME'),
+                                       when=app.config.get('ROLLOVER'),
+                                       interval=app.config.get('INTERVAL'),
+                                       backupCount=app.config.get('BACKUP_COUNT'))
+    logging.getLogger().addHandler(handler)
+
 
 class MyIndexView(IndexView):
     @expose('/')

caravel/config.py

@@ -130,6 +130,29 @@
 
 VIZ_TYPE_BLACKLIST = []
 
+"""
+1) http://docs.python-guide.org/en/latest/writing/logging/
+2) https://docs.python.org/2/library/logging.config.html
+"""
+
+# Console Log Settings
+
+LOG_FORMAT = '%(asctime)s:%(levelname)s:%(name)s:%(message)s'
+LOG_LEVEL = 'DEBUG'
+
+# ---------------------------------------------------
+# Enable Time Rotate Log Handler
+# ---------------------------------------------------
+# LOG_LEVEL = DEBUG, INFO, WARNING, ERROR, CRITICAL
+
+ENABLE_TIME_ROTATE = False
+TIME_ROTATE_LOG_LEVEL = 'DEBUG'
+FILENAME = '/tmp/caravel.log'
+ROLLOVER = 'midnight'
+INTERVAL = 1
+BACKUP_COUNT = 30
+
+
 try:
     from caravel_config import *  # noqa
 except Exception: