lotconfig 1.3

# Lord of the Config

Lord of the Config is a super-simple YAML-based configuration system. No more meaningless key-checking or file creation. LOTConfig makes it easy to create, manage, and write configurations.

Repository: https://bitbucket.org/bear_belly/lord_of_the_config

## Examples

Here are some quick-and-dirty examples for how the engine works:

Python 3.6.3 (default, Oct  3 2017, 21:45:48)
[GCC 7.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from lotconfig import Config
>>> config = Config.load_or_create("sample.yaml")
>>> config['basic/thing']
    'my_value'

## Loading a config

Configs are loaded from YAML files. To load a config use the Config.load, method or–better yet–the Config.load_or_create() method for fool-proof config loading. This will create the file if it doesn’t exist.

## Accessing config values

To access configuration values, you can either use config.get() or dict-like access:

# This will return “default_value” if nothing is set in ‘/path/to/param’ config.get(‘path/to/param’, ‘default_value’) # This will just return None if nothing is set in ‘/path/to/param’ config[‘/path/to/param’]

You can use typical dict functions, too, like in.

## Setting Configuration Values

Woah, there tiger! Unfortunately this isn’t implemented yet. Since LOTConfig implements advanced features (see below), setting a configruation value is pretty intensive.

Hopefully it’ll happen in the future.

In the meantime you’ll be greeted with an Exception if you try to do this.

## Writing a configuration

To write a configuration, call config.write() or config.write_stream().

## Advanced features

### Modes

Modes are special keywords in the yaml configuration.

There’s a default keyword you can specify at the beginning of the file to specify a mode. For example:

mode: development

This mode can be used throughout the file to specify different environments. For the mode value, prefix it with ‘@’ (and make sure to surround it with quotes, since YAML doesn’t like ‘@’ for keys). For example:

server:

‘@development’:

host: localhost port: 5000

‘@production’:

host: example.com port: 5000

This way, whenever mode is 'production', you can refer server will automatically refer to {host: "example.com", "port": 5000}, and if mode is set to developemnt, then server will refer to {host: "localhost", "port": 5000}.

IMPORTANT. These mode keys are essentially invisible. You can’t force the configuation to read config['server/@development/host'].

So if mode is production config['server/host'] is example.com. If mode is development config['server/host'] is localhost.

### References

Don’t repeat yourself. You can refer to another value within the config using a key reference. Key references are strings that refer to other config values.

References are preceded with a tilde (~).

Consider the following example:

database:

home: ~server1 remote: ~server2

hardware:

servers:

server1: 192.168.0.1 server2: 192.168.0.2

This would result in the following configuration:

>> config[‘database/home’]

‘192.168.0.1’

>> config[‘database/remote’]

‘192.16.0.2’

See? References help you to reduce the amount you have to type. You can even use it for complex configurations:

letter_a:

category_a: ~cat_a category_b: ~cat_b

letter_b:

cat_a:

item_a: 1 item_b: false

cat_b:

item_a: 19 item_b: 20

This would result in the following configuration:

>> config[‘letter_a/category_a’]

{‘item_a’: 1, ‘item_b’: false}

### evals

Evals are probably the most powerful fo the bunch. They evaluate raw Python code. As such, use LOTConfig only on configuration files you trust. In future versions a paramter may be passed to turn on evaluations.

Evals begin with the keyword eval>>. The result is always a raw string. For example:

key: eval>> 1+2 # results in config[‘key’] -> ‘3’

Two modules are available to be evaluated: os and env.

key: eval>> os.environ[‘DISPLAY’] # results in config[‘key’] -> ‘:0’

Home-page: UNKNOWN Author: Jordan Hewitt Author-email: [e-mail] License: GPLv3 Description-Content-Type: UNKNOWN Description: UNKNOWN Platform: UNKNOWN