feat: INI support (#17)

tests/config.ini

@@ -0,0 +1,4 @@
+[simple_app]
+arg1 = stuff
+opt1 = things
+opt2 = nothing

tests/test_example.py

@@ -41,6 +41,14 @@ def test_simple_example(simple_app):
         (str(HERE.joinpath("config.json")), typer_config.json_conf_callback),
         (str(HERE.joinpath("config.toml")), typer_config.toml_conf_callback),
         (str(HERE.joinpath("config.env")), typer_config.dotenv_conf_callback),
+        (
+            str(HERE.joinpath("config.ini")),
+            typer_config.conf_callback_factory(
+                typer_config.loaders.subpath_loader(
+                    typer_config.loaders.ini_loader, ["simple_app"]
+                )
+            ),
+        ),
     ]
 
     # Test all the combinations of formats and extra parameters

typer_config/loaders.py

@@ -5,6 +5,7 @@
 """
 import json
 import sys
+from configparser import ConfigParser
 
 from .__typing import (
     ConfigDict,
@@ -212,3 +213,32 @@ def dotenv_loader(param_value: TyperParameterValue) -> ConfigDict:
         conf: ConfigDict = dotenv.dotenv_values(stream=_file)
 
     return conf
+
+
+def ini_loader(param_value: TyperParameterValue) -> ConfigDict:
+    """INI file loader
+
+    Note:
+        INI files must have sections at the top level.
+        You probably want to combine this with `subpath_loader`.
+        For example:
+        ```py
+        ini_section_loader = subpath_loader(ini_loader, ["section"])
+        ```
+
+    Args:
+        param_value (TyperParameterValue): path of INI file
+
+    Returns:
+        ConfigDict: dictionary loaded from file
+    """
+
+    ini_parser = ConfigParser()
+    with open(param_value, "r", encoding="utf-8") as _file:
+        ini_parser.read_file(_file)
+
+    conf: ConfigDict = {
+        sect: dict(ini_parser.items(sect)) for sect in ini_parser.sections()
+    }
+
+    return conf