settings-helper 0.0.13

Helpers to get specific settings from a particular section of a settings.ini file

You must include at least one section header in your settings.ini file (like [default]). The configparser will raise a MissingSectionHeaderError if no headers are defined.

If you have any additional section headers, each parsed section will only contain things defined in that section, plus anything defined in the special/optional [default] section.

The values of any variable names in any sections can be overwritten by the value set for an environment variable of the same name (or it’s ALLCAPS name).

Any variables that have multiple values separated by a comma will be converted to a list.

The parsed values will be converted to their basic types (int, float, None, bool, str) via the from_string or string_to_converted_list functions from input-helper for easy use.

You can comment out any variables in the settings.ini file with a leading #.

Setup for a one-off script

Create a settings.ini file next to your script with at least one section header in square brackets (like [my stuff]).

[my stuff]
something = 100
things = none, true, false, 1, 2.5, dogs and cats, grapes
# other = 500

Use the simple get_all_settings function to get a dict of all settings by section header.

import settings_helper as sh

settings = sh.get_all_settings()

For our settings.ini file example, the settings dict from get_all_settings() would be the following:

{
    'my stuff': {
        'something': 100,
        'things': [None, True, False, 1, 2.5, 'dogs and cats', 'grapes']
    }
}

Setup in your package

Create a default/sample settings.ini file in the module directory of your package, with a [default] section and any other [sections] you want (i.e. app environments)

[default]
something = 100

[dev]
redis_url = redis://localhost:6379/1
something = 500

[test]
redis_url = redis://localhost:6379/9
things = none, true, false, 1, 2.5, dogs

For this settings.ini file example, the settings dict from get_all_settings() would be the following:

{
    'dev': {
        'something': 500,
        'redis_url': 'redis://localhost:6379/1'
    },
    'default': {
        'something': 100
    },
    'test': {
        'something': 100,
        'redis_url': 'redis://localhost:6379/9',
        'things': [None, True, False, 1, 2.5, 'dogs']
    }
}

Create a MANIFEST.in file in your package directory with the following

include settings.ini

Update the setup.py file of the package to include the setting.ini file and add settings-helper to install_requires list

from setuptools import setup, find_packages

setup(
    name='package-name',
    version='0.0.1',
    ...
    packages=find_packages(),
    install_requires=[
        'settings-helper',
        ...
    ],
    include_package_data=True,
    package_dir={'': '.'},
    package_data={
        '': ['*.ini'],
    },
    ...
)

Note, your package directory tree will be something like the following

package-name
├── .gitignore
├── LICENSE.txt
├── MANIFEST.in
├── README.md
├── README.rst
├── package_name/
│   ├── __init__.py
│   └── settings.ini
└── setup.py

Usage

Use in __init__.py of package

import settings_helper as sh

get_setting = sh.settings_getter(__name__)
something = get_setting('something')
something_else = get_setting('something_else', 'default_val')

Set APP_ENV environment variable to be one of your section names when starting your Python interpreter/server. ``APP_ENV`` defaults to ``dev`` if it is not set.

• The get_setting func will return the value of the requested variable if it is set in the section specified in APP_ENV.

• If the variable is not in the section, it will pull the value from the [default] section

• If the varialbe is not in the [default] section either, then return the optional fallback value passed in the default keyword argument to get_setting (which defaults to an empty string)

• If the requested variable exists in the environment (or its uppercase equivalent), it will be used instead of getting from settings.ini

• The value is automatically converted to a bool, None, int, or float if it should be

• If the value contains any of (, ; |) then a list of converted values will be returned

The first time that settings_getter func is invoked, it looks for a settings.ini file in ~/.config/<package-name>/settings.ini.

• If it does not find it, it will copy the default settings.ini from the module’s install directory to that location

• If the settings.ini file does not exist in the module’s install directory, an exception is raised

Alternate Usage

import settings_helper as sh

settings = sh.get_all_settings(__name__)

or

import settings_helper as sh

settings = sh.get_all_settings(__name__).get(sh.APP_ENV, {})

The get_all_settings func returns a dict containing all section headers. ‘default’ .

• If a setting is defined in ‘default’, but not in a particular section, the setting in ‘default’ will appear under the section

• If a setting (or upper-case equivalent) is defined as an environment variable, that value will be used for all sections that use it

Tip

In your <package-name>/tests/__init__.py file, add the following so the test section of settings is automatically used

import os

os.environ['APP_ENV'] = 'test'