configbuilder

General purpose configuration parser builder for python. You can create your own configuration parser only with Configuration Template

configbuilder offers you the easiest way to define a configuration file for your application project written in python.

Synopsis

Data serialization language such as YAML or JSON is a good choice to write a configuration files for a application. The code for parsing and validating the configuration file have to be re-written even for a simple change such as attribute name modification for new application. configbuilder offers you an easy way to define a configuration file format with minimum code changing. It is even possible to define a configuration format without any developing codes. Instead of parsing code, you can define a configuration with a template file written in data serialization language.

Usage

Configuration Template

You can define the format of configuration format with writing a configuration template. Loading the configuration template in your application code, you can simply parse a user configuration file also with the validation. This is the example of a configuration template written in YAML.

ConfigKey1: String
ConfigKey2: Boolean
ConfigKey3: Integer
ConfigKey4: IP
ConfigKey5: FilePath
ConfigKey6:
    ConfigKey6Name: # indicates the name of this subconfig
        SubConfigKey1: List of DirectoryPath 
        SubConfigKey2: String
        SubConfigKey3:
            SubConfigKey3Name:
                SubSubConfigKey1: List of String
                SubSubConfigKey2: Integer
                SubSubConfigKey3: IP
            SubConfigKey3Name:
                SubSubConfigKey4: Config In SubConfigKey3
ConfigKey7:
    -   
        SubConfigKey1: String
        SubConfigKey2: Integer
        SubConfigKey3: NotSupportingType

An Attribute in configuration template consists of Key:Type pair. A key without a type intends that there is a sub-config for the key. There are built-in types to validate values. The types are case-insensitive.

Built-in types

String: Any type of string is accepted, and automatically strip the string.
Boolean: True or False
Integer: Integers
IP: IP address
Path: Any path regardless of the existence
FilePath: Existing file path
DirectoryPath: Existing directory path
List: Any list regardless of the type of the item

Compound type

List of Built-in type: The value should be a list, and each item is validated with the specified built-in type.
Config In Other Configuration Key: The value is the name of other configuration. This type converts value into the configuration instead of the given name.

Build parser

Simple function create_parser let you build your own parser. With your parser, you are ready to parse your configuration file.

from configbuilder.parser import create_parser
parser = create_parser('path/your_template.yaml',
                       casesensitivekey=False)
config = parser.parse_config('path/your_configuration.yaml')
value = config.get('attribute')

Or you can define your template in your code in dictionary type, and create the parser.

from configbuilder.parser import ConfigParser
YOUR_TEMPLATE = {
    'KEY1': 'String',
    'KEY2': 'Integer'
}
parser = ConfigParser(YOUR_TEMPLATE)

Define new types

You can define your own validator inheriting Validator class and set to parser. You implement validate_yourtype() in your custom validator to define new type called yourtype. This type can be used in the template file. Here is the code defining a new type called protocol which is kind of string, but only accpeting 'ssh' or 'ftp' as the value.

from configbuilder.validator import Validator
class MyValidator(Validator):
    def validate_protocol(self, value):
        supporting_protocol = ['ssh', 'ftp'] 
        return self._validate_choiceses(value, supporting_protocol)

This validator can be set when building the parser.

parser = create_parser('path/your_template.yaml',
                       validator=MyValidator())

Installation

pip install configbuilder

Authors

** Joong-Hee Lee ** - Initial work - joongh

License

This project is licensed under the MIT License - see the LICENSE.md file for details

joongh/configbuilder