yaml2pyclass 0.1.2

Code generator that produces a Python class from a YAML input file. Can be used to facilitate code completion for config objects.

yaml2pyclass Code Generator

This package enables you to easily generate and instantiate dataclasses from an input YAML file. For example this YAML file

image_size: [ 1280, 960 ]
cluster_config:
  eps: 0.02
  min_num_samples: 10
path_output: "./output"

automatically converts to a Python class

import dataclasses
import yaml2pyclass

class Config(yaml2pyclass.CodeGenerator):
    @dataclasses.dataclass
    class ClusterConfigClass:
        eps: float
        min_num_samples: int

    image_size: list
    cluster_config: ClusterConfigClass
    path_output: str

In addition to code creation, an instance of the generated class that is initialized with the YAMLs values can be created automatically.

The use case it was primarily developed for is facilitating code completion for arbitrary YAML config files. Using YAML files as input config allows flexible and general information passing, however, when using pyyaml the information is saved as a dict which does not support any automatic code completion. This means, that you need to know the exact variable names for access.

Using this package you can enjoy YAMLs flexibility and generality, while additionally providing the benefit of code completion and type specific suggestions from your IDE. Thus, no need to memorize exact variable names or types.

Installation

You can install the package using pip

pip install yaml2pyclass

Usage

File Update

To update an existing file, as e.g. in the case of a config file, you need to create a base file. The base file (e.g. at path/to/config.py) should simply contain a class, that inherits from the yaml2pyclass base class CodeGenerator:

import yaml2pyclass


class Config(yaml2pyclass.CodeGenerator):
    # content is updated automatically from the specified YAML file
    pass

Then, in the function where you want to use this class based on the YAML input, import the created class and call the from_yaml function

from path.to.config import Config  # import the class Config from the path/to/config.py file

config = Config.from_yaml("config.yaml")

This will update the file of the Config class with dataclass that matches the input YAML.

Contributors

This project is a collaboration with Felix Hertlein.

License

This code is distributed under the 3-Clause BSD License, see LICENSE.