configuration file initial support

Author: chubin

etc/config.yaml

@@ -0,0 +1,7 @@
+server:
+    address: "0.0.0.0"
+    port:    8002
+    cache:   false      # true - results have to be cached in redis
+                        # false - results do not have to be cached locally
+                        # "path" results have to be cached in filesystem
+    redis:   false      # redis server hostname of false if no redis server used

lib/globals.py

@@ -1,17 +1,23 @@
 """
 Global configuration of the project.
-All hardcoded paths should be (theoretically) here.
+All hardcoded pathes and other data should be
+(theoretically) here.
 """
 from __future__ import print_function
 
 import logging
 import os
+import yaml
 from pygments.styles import get_all_styles
 
 USE_OS_PACKAGES = True  # set to False if you pull cheat sheets repositories from GitHub
 DOCKERIZED = False      # set to True if the service is running in a Docker container
 
+SERVER_ADDRESS = '0.0.0.0'
+SERVER_PORT = 8002
+
 MYDIR = os.path.abspath(os.path.join(__file__, '..', '..'))
+_CONF_FILE = os.path.join(MYDIR, 'etc/config.yaml')
 
 if DOCKERIZED:
     REDISHOST = 'redis'
@@ -39,6 +45,20 @@
     PATH_CHEAT_SHEETS_SPOOL = os.path.join(MYDIR, "cheatsheets/spool/")
     PATH_LEARNXINY = os.path.join(MYDIR, "cheatsheets/learnxinyminutes-docs")
 
+#
+# Reading configuration from etc/config.yaml
+# config overrides default settings
+#
+if os.path.exists(_CONF_FILE):
+    _CONFIG = yaml.load(_CONF_FILE)
+    if 'server' in _CONFIG:
+        _SERVER_CONFIG = _CONFIG['server']
+        if 'address' in _SERVER_CONFIG:
+            SERVER_ADDRESS = _SERVER_CONFIG['address']
+        if 'port' in _SERVER_CONFIG:
+            SERVER_ADDRESS = _SERVER_CONFIG['port']
+
+
 COLOR_STYLES = sorted(list(get_all_styles()))
 
 MALFORMED_RESPONSE_HTML_PAGE = open(os.path.join(STATIC, 'malformed-response.html')).read()