Merge pull request #288 from timrichardson/app_config_v2

typo and other fixes for appconfig.ini

sources/29-web2py-english/13.markmin

@@ -1,27 +1,40 @@
 
 ## Deployment: development and production
+``appconfig``:inxx
+[[appconfig]]
+### AppConfig module
+
 The environment between your development and production system will almost certainly mean a different database configuration, different mail servers and possibly other differences.
 
-Web2py uses the private directory for storing information which is not replicated in a typical deployment to productoin. 
+Web2py intends the private directory for storing information which is not replicated in a typical deployment to production (although you need to take care to make sure that you are not deploying that directory). 
+
 The contributed module ``AppConfig`` allows the private directory to store a simple configuration text file to define settings which vary between dev and production, such as database connections. By default it is a text file which is pythonesque, but json is also supported.
 
 The welcome app now uses this module in ``db.py`` to read configuration from a file in the application's private directory. By default the path to this file is 
 ``private/app_config.ini``
-Private directories are ignored by git in the default web2py settings, as the private folder is designed to be a safe place to store sensitive information. 
-
-An easy way to learn about this module is to create a new app an inspect the default usage. 
 
-By default, app_config.ini allows you to define a database connection and smtp configuration. When the application is stable, the module can be set to cached mode to reduce overhead.
+By default, ``app_config.ini`` allows you to define a database connection and smtp configuration. When the application is stable, the module can be set to cached mode to reduce overhead.
 ``
 from gluon.contrib.appconfig import AppConfig
 ...
 myconf = AppConfig(reload=False)``:code
 
 Applications created in a recent version of web2py default to having the database connection defined with AppConfig. 
 
+The values in app_config.ini are fetched and cast from a string value by like so:
+``
+myconf = AppConfig()
+...
+a_config_value = myconf.take('example_section.example_key',cast=int)
+``:code
+
+Because the casting occurs from a string, and non empty strings cast to True, the safest way to represent a Boolean False is with an empty string:
+``
+[example_section]
+example_key = 
+``:code
 
 ## Deployment recipes: Infrastructure
-
 There are multiple ways to deploy web2py in a production environment. The details depend on the configuration and the services provided by the host.
 
 In this chapter we consider the following issues: