Skip to main content

I/O facility for Idefix/Pluto configuration files

Project description

inifix

PyPI PyPI pre-commit.ci status Code style: black Ruff

inifix is a small Python library of I/O functions to read and write 'ini' configuration files in the style of Pluto and Idefix.

While its primary goal is to follow Idefix's 'ini' format specification, it supports a small superset of it.

The key differences are:

  • inifix supports section-free definitions. This means configuration files from FARGO 3D are also supported.
  • in inifix, strings can be escaped using ' or ". This allows to have whitespaces in string values and to force string type decoding where numeric and boolean types would work.

In rare cases where Idefix's 'ini' format doesn't match Pluto's, inifix will follow the former. Known differences are:

  • Idefix allows booleans to be written as yes and no.
  • Idefix allows integers to be written using scientific notation (e.g. 1e3)

File format specifications details

Unroll ! - parameter names are strings - names and values are separated by non-newline white spaces - values are represented in unicode characters - all values are considered numbers if possible (e.g., `1e3` is read as `1000`) - number values are read as integers if no loss of precision ensues, and floats otherwise - `true` and `false` (resp. `yes` and `no`) are cast to booleans (case-insensitive) - values that can't be read as number or booleans are read as strings. - string delimiters `"` and `'` can be used for strings containing whitespace, or to force string type for values that would otherwise be read as numbers and booleans. - a parameter can be associated to a single value or a list of whitespace-separated values - sections titles start with `[` and end with `]` - comments start with `#` and are ignored

A file is considered valid if calling inifix.load(<filename>) doesn't raise an error.

Examples

The following content is considered valid

# My awesome experiment
[Grid]
x   1 2 u 10    # a comment
y   4 5 l 100
[Time Integrator]
CFL  1e-3
tstop 1E3

and maps to

{
    "Grid": {
        "x": [1, 2, "u", 10],
        "y": [4, 5, "l", 100]
    },
    "Time Integrator": {
        "CFL": 0.001,
        "tstop": 1000.0
    }
}

The following section-less format doesn't comply to Pluto/Idefix's specifications, but it is considered valid for inifix. This is the one intentional differences in specifications, which makes inifix format a superset of Pluto's inifile format.

mode   fargo

# Time integrator
CFL    1e-3
tstop  1e3

and maps to

{
    "mode": "fargo",
    "CFL": 0.001,
    "tstop": 1000.0
}

Note that strings using e-notation (e.g. 1e-3 or 1E3 here) are decoded as floats. Reversely, when writing files, floats are re-encoded using e-notation if it leads to a more compact representation. For instance, 100000.0 is encoded as 1e5, but 189.0 is left unchanged because 1.89e2 takes one more character. In cases where both reprensations are equally compact (e.g. 1.0 VS 1e0), decimal is prefered in encoding.

While decoding, e can be lower or upper case, but they are always encoded as lower case.

Installation

python -m pip install inifix

Usage

The public API mimicks that of Python's standard library json, and consists in four main functions:

  • inifix.load and inifix.dump read from and write to files respectively
  • inifix.loads reads from a str and returns a dict, while inifix.dumps does the reverse operation.

Reading data

inifix.load reads from a file and returns a dict

import inifix

with open("pluto.ini", "rb") as fh:
    conf = inifix.load(fh)

# or equivalently
conf = inifix.load("pluto.ini")

Files are assumed to be encoded as UTF-8.

inifix.load and inifix.loads accept a optional boolean flag parse_scalars_as_list (new in inifix v4.0.0), that is useful to simplify handling unknown data: all values can be safely treated as arrays, and iterated over, even in the presence of scalar strings. For illustration

>>> import inifix
>>> from pprint import pprint
>>> pprint(inifix.load("example.ini"))
{'Grid': {'x': [1, 2, 'u', 10], 'y': [4, 5, 'l', 100]},
 'Time Integrator': {'CFL': 0.001, 'tstop': 1000.0}}
>>> pprint(inifix.load("ex.ini", parse_scalars_as_lists=True))
{'Grid': {'x': [1, 2, 'u', 10], 'y': [4, 5, 'l', 100]},
 'Time Integrator': {'CFL': [0.001], 'tstop': [1000.0]}}

... and writing back to disk

inifix.dump allows to write back to a file.

This allows to change a value on the fly and create new configuration files programmatically, for instance.

conf["Time"]["CFL"] = 0.1

with open("pluto-mod.ini", "wb") as fh:
    inifix.dump(conf, fh)

# or equivalently
inifix.dump(conf, "pluto-mod.ini")

Data will be validated against inifix's format specification at write time. Files are always encoded as UTF-8.

Schema Validation

inifix.validate_inifile_schema can be used to validate an arbitrary dictionary as writable to an inifile, following Pluto/Idefix's format. This will raise an exception (ValueError) if the dictionnary data is invalid.

inifix.validate_inifile_schema(data)

CLI

Command line tools are shipped with the package to validate or format compatible inifiles.

Validation

This checks that your inifiles can be loaded with inifix.load from the command line

$ inifix-validate pluto.ini
Validated pluto.ini

This simple validator can be used as a hook for pre-commit. Simply add the following to your project's .pre-commit-config.yaml

  - repo: https://github.com/neutrinoceros/inifix.git
    rev: v4.2.1
    hooks:
      - id: inifix-validate

Formatting

To format a file in place, use

$ inifix-format pluto.ini

inifix-format is guaranteed to preserve comments and to only edit (add or remove) whitespace characters.

Files are always encoded as UTF-8.

Options

  • To print a diff patch to stdout instead of editing the file, use the --diff flag
$ inifix-format pluto.ini --diff

This program also doubles as pre-commit hook

  - repo: https://github.com/neutrinoceros/inifix.git
    rev: v4.2.1
    hooks:
      - id: inifix-format

Testing

We use the pytest framework to test inifix. The test suite can be run from the top level with a simple pytest invocation.

$ python -m pip install --requirement requirements/tests.txt
$ pytest

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

inifix-4.2.1.tar.gz (32.0 kB view details)

Uploaded Source

Built Distribution

inifix-4.2.1-py3-none-any.whl (26.2 kB view details)

Uploaded Python 3

File details

Details for the file inifix-4.2.1.tar.gz.

File metadata

  • Download URL: inifix-4.2.1.tar.gz
  • Upload date:
  • Size: 32.0 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No
  • Uploaded via: twine/4.0.1 CPython/3.11.2

File hashes

Hashes for inifix-4.2.1.tar.gz
Algorithm Hash digest
SHA256 ee19c6af7c053465a387deb2e21f70c7913f0bf8437f8d05b75f41445fe5499b
MD5 17e099a901394d0fec24b2da304abe1a
BLAKE2b-256 1a8b16f4f57aed123e3af78fec999bbd25c89e86a956b2f8595fcef6f095fd65

See more details on using hashes here.

File details

Details for the file inifix-4.2.1-py3-none-any.whl.

File metadata

  • Download URL: inifix-4.2.1-py3-none-any.whl
  • Upload date:
  • Size: 26.2 kB
  • Tags: Python 3
  • Uploaded using Trusted Publishing? No
  • Uploaded via: twine/4.0.1 CPython/3.11.2

File hashes

Hashes for inifix-4.2.1-py3-none-any.whl
Algorithm Hash digest
SHA256 c275e758c1c73047ccf6439e58f14a98a84e8c8a7885dfcfa0a6c5e93b3e54f5
MD5 e503506770009319bb845d6c051dec71
BLAKE2b-256 f0f8ec6849ff9da1866d144d5a2f16f7090c4222fb6790a15b5eec30ff2236fc

See more details on using hashes here.

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page