Typer Config

https://manderscience.com/typer-config/latest
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Typer Config provides utilities to use configuration files (YAML, JSON, TOML, INI, dotenv) to set...
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### Command-Line Invocation Examples

Source: https://manderscience.com/typer-config/latest/examples/schema

These examples demonstrate how to invoke the Python Typer application using the `--config` option to load the YAML configuration file. They show different ways to override or provide arguments and options.

```bash
$ python simple_app.py --config config.yml

```

```bash
$ python simple_app.py --config config.yml others

```

```bash
$ python simple_app.py --config config.yml --opt1 people

```

--------------------------------

### Install Typer Config

Source: https://manderscience.com/typer-config/latest/install

Installs the base Typer Config library. This is the minimal installation required to use the library.

```bash
pip install typer-config
```

--------------------------------

### Terminal Invocation Examples

Source: https://manderscience.com/typer-config/latest/examples/default_config

These terminal commands illustrate how to invoke the Typer application with different configurations. They show the default behavior, overriding arguments, and specifying an alternative configuration file.

```bash
$ python simple_app.py
things nothing stuff

$ python simple_app.py others
things nothing others

$ python simple_app.py --opt1 people
people nothing stuff

$ python simple_app.py --config other.yml
foo bar baz

```

--------------------------------

### Install Optional Dependencies for File Formats

Source: https://manderscience.com/typer-config/latest/install

Installs optional dependency sets for Typer Config to support additional file formats. Each command installs support for a specific format (YAML, TOML, python-dotenv) or all formats.

```bash
pip install typer-config[yaml] # includes pyyaml
```

```bash
pip install typer-config[toml] # includes toml
```

```bash
pip install typer-config[python-dotenv] # includes python-dotenv
```

```bash
pip install typer-config[all] # includes all optional dependencies
```

--------------------------------

### Invoking Typer App with YAML Config (Terminal)

Source: https://manderscience.com/typer-config/latest/examples/simple_yaml

Examples demonstrating how to run the Typer application from the terminal using the `--config` option to specify a YAML configuration file. Shows how command-line arguments and options can override or supplement the configuration file.

```bash
$ python simple_app.py --config config.yml
things nothing stuff

$ python simple_app.py --config config.yml others
things nothing others

$ python simple_app.py --config config.yml --opt1 people
people nothing stuff

```

--------------------------------

### YAML: Example Configuration for List Arguments

Source: https://manderscience.com/typer-config/latest/known_issues

This YAML file provides an example configuration for the Python script that handles list arguments. It shows how to specify values for string, option, and list arguments directly within the config file, which can then be loaded by typer-config.

```yaml
# config.yml
opt1: "apple"
opt2: "pear"
arg1: "lemon"
arg2: ["oak", "aspen", "maple"]

```

--------------------------------

### Quickstart: Add YAML Config to Typer App

Source: https://manderscience.com/typer-config/latest/index

Demonstrates how to use the `use_yaml_config` decorator to automatically add a `--config` option to a Typer application. This decorator must be placed after the `@app.command()` decorator. It enables loading parameters from a YAML configuration file.

```python
import typer
from typer_config import use_yaml_config  # other formats available 

app = typer.Typer()


@app.command()
@use_yaml_config()  # MUST BE AFTER @app.command() 
def main(foo: FooType): ...


if __name__ == "__main__":
    app()
```

--------------------------------

### YAML Configuration File Example

Source: https://manderscience.com/typer-config/latest/examples/pydantic

An example YAML file defining configuration parameters for the Typer application. This file is used to provide values for 'arg1', 'opt1', and 'opt2', which are then validated by the Pydantic model in the Python script. The structure of this file must match the fields defined in the 'AppConfig' Pydantic model.

```yaml
arg1: stuff
opt1: things
opt2: nothing

```

--------------------------------

### Command-Line Invocation Examples

Source: https://manderscience.com/typer-config/latest/examples/explicit_config

These terminal commands demonstrate how to invoke the Typer application with an explicit YAML configuration file. They show how the configuration is applied and how command-line arguments can override or supplement the config file settings.

```bash
$ python simple_app.py --config config.yml
# Expected output: things nothing stuff

$ python simple_app.py --config config.yml others
# Expected output: things nothing others

$ python simple_app.py --config config.yml --opt1 people
# Expected output: people nothing stuff

```

--------------------------------

### Load YAML Configuration File

Source: https://manderscience.com/typer-config/latest/api

Loads configuration from a YAML file into a ConfigDict. Requires the 'pyyaml' library to be installed. Takes a file path as input and returns a dictionary representing the configuration.

```python
from typing import Dict, Any
from pathlib import Path

from .__optional_imports import try_import

TyperParameterName = str
TyperParameterValue = Any
ConfigDict = Dict[TyperParameterName, Any]
FilePath = Union[Path, str]

def yaml_loader(param_value: TyperParameterValue) -> ConfigDict:
    """YAML file loader.

    Args:
        param_value (TyperParameterValue): path of YAML file

    Raises:
        ModuleNotFoundError: pyyaml library is not installed

    Returns:
        ConfigDict: dictionary loaded from file
    """

    yaml = try_import("yaml")

    if yaml is None:  # pragma: no cover
        message = "Please install the pyyaml library."
        raise ModuleNotFoundError(message)

    with open(param_value, "r", encoding="utf-8") as _file:
        conf: ConfigDict = yaml.safe_load(_file)

    return conf

```

--------------------------------

### Example Pyproject TOML Configuration

Source: https://manderscience.com/typer-config/latest/examples/pyproject

This TOML snippet shows the structure of the `pyproject.toml` file, specifically the `[tool.my_tool.parameters]` section, which contains the configuration values that the custom Typer CLI loader will read.

```toml
[tool.my_tool.parameters]
arg1 = "stuff"
opt1 = "things"
opt2 = "nothing"

```

--------------------------------

### Typer App with YAML Config

Source: https://manderscience.com/typer-config/latest/examples/default_config

This Python script defines a Typer application that automatically loads configuration from a 'config.yml' file by default. It uses the `use_yaml_config` decorator from `typer_config.decorators`. The application accepts arguments and options, which can be overridden by command-line inputs.

```python
from typing_extensions import Annotated

import typer
from typer_config.decorators import use_yaml_config  # other formats available 

app = typer.Typer()


@app.command()
@use_yaml_config(default_value="config.yml")
def main(
    arg1: str,
    opt1: Annotated[str, typer.Option()],
    opt2: Annotated[str, typer.Option()] = "hello",
):
    typer.echo(f"{opt1} {opt2} {arg1}")


if __name__ == "__main__":
    app()

```

--------------------------------

### TOML File Loader

Source: https://manderscience.com/typer-config/latest/api

Loads configuration data from a TOML file. It attempts to use the `tomllib` library first and falls back to the `toml` library if `tomllib` is not available. Requires the 'toml' library to be installed if `tomllib` is not found.

```APIDOC
## toml_loader

### Description
TOML file loader. Attempts to use `tomllib` and falls back to `toml`. Requires the `toml` library if `tomllib` is unavailable.

### Method
N/A (Function)

### Endpoint
N/A (Function)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```python
# try:
#     config = toml_loader("path/to/your/config.toml")
# except ModuleNotFoundError as e:
#     print(e) # 'Please install the toml library.'
```

### Response
#### Success Response (200)
- **ConfigDict** (`ConfigDict`) - dictionary loaded from file

#### Response Example
```json
{
  "title": "TOML Example",
  "owner": {
    "name": "Tom",
    "dob": "1979-05-27T07:32:00-08:00"
  }
}
```

### Error Handling
- **ModuleNotFoundError**: Raised if the `toml` library is not installed and `tomllib` is not available.
```

--------------------------------

### YAML Loader

Source: https://manderscience.com/typer-config/latest/api

Loads configuration from a YAML file. This function requires the 'pyyaml' library to be installed.

```APIDOC
## yaml_loader

### Description
YAML file loader.

### Method
Not applicable (this is a function)

### Endpoint
Not applicable (this is a function)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
- **param_value** (TyperParameterValue) - Required - Path to the YAML file.

### Request Example
```python
# Example usage within a Typer application
# Assume 'config_loader' is a function that calls yaml_loader

# config_loader("path/to/your/config.yaml")
```

### Response
#### Success Response (200)
- **ConfigDict** (ConfigDict) - A dictionary representing the loaded configuration.

#### Response Example
```json
{
  "key1": "value1",
  "nested": {
    "subkey": "subvalue"
  }
}
```

### Errors
- **ModuleNotFoundError**: Raised if the `pyyaml` library is not installed.
```

--------------------------------

### Dump Configuration to TOML File with Python

Source: https://manderscience.com/typer-config/latest/api

The `toml_dumper` function serializes a `ConfigDict` object to a specified file location in TOML format. It requires the 'toml' library to be installed, and raises a `ModuleNotFoundError` if it is not available. The function takes the configuration dictionary and the file path as arguments.

```python
def toml_dumper(config: ConfigDict, location: FilePath) -> None:
    """Dump config to TOML file.

    Args:
        config (ConfigDict): configuration
        location (FilePath): file to write

    Raises:
        ModuleNotFoundError: toml library is required for writing files
    """

    toml = try_import("toml")

    if toml is None:  # pragma: no cover
        message = "Please install the toml library to write TOML files."
        raise ModuleNotFoundError(message)

    with open(location, "w", encoding="utf-8") as _file:
        toml.dump(config, _file)  # type: ignore

```

--------------------------------

### Load Configuration from Dotenv Files in Python

Source: https://manderscience.com/typer-config/latest/api

The `dotenv_loader` function loads configuration settings from a specified .env file. It requires the `python-dotenv` library to be installed. If the library is not found, it raises a `ModuleNotFoundError`. The function returns a dictionary representing the loaded configuration.

```python
from typing import Dict

from dotenv import dotenv_values

from typer_config.config import ConfigDict, TyperParameterValue

def dotenv_loader(param_value: TyperParameterValue) -> ConfigDict:
    """Dotenv file loader.

    Args:
        param_value (TyperParameterValue): path of Dotenv file

    Raises:
        ModuleNotFoundError: python-dotenv library is not installed

    Returns:
        ConfigDict: dictionary loaded from file
    """

    dotenv = try_import("dotenv")

    if dotenv is None:  # pragma: no cover
        message = "Please install the python-dotenv library."
        raise ModuleNotFoundError(message)

    with open(param_value, "r", encoding="utf-8") as _file:
        # NOTE: I'm using a stream here so that the loader
        # will raise an exception when the file doesn't exist.
        conf: ConfigDict = dotenv.dotenv_values(stream=_file)

    return conf

```

--------------------------------

### Load TOML Configuration File

Source: https://manderscience.com/typer-config/latest/api

Loads configuration from a TOML file into a ConfigDict. This loader attempts to use the `tomllib` module first (available in Python 3.11+) and falls back to the `toml` library if `tomllib` is not found. It requires either `tomllib` or the `toml` package to be installed. The function takes the path to the TOML file and returns its parsed content.

```python
def toml_loader(param_value: TyperParameterValue) -> ConfigDict:
    """TOML file loader.

    Args:
        param_value (TyperParameterValue): path of TOML file

    Raises:
        ModuleNotFoundError: toml library is not installed

    Returns:
        ConfigDict: dictionary loaded from file
    """

    # try `tomllib` first
    tomllib = try_import("tomllib")

    if tomllib is not None:
        with open(param_value, "rb") as _file:
            return tomllib.load(_file)

    # couldn't find `tommllib`, so try `toml`
    toml = try_import("toml")

    if toml is None:  # pragma: no cover
        message = "Please install the toml library."
        raise ModuleNotFoundError(message)

    with open(param_value, "r", encoding="utf-8") as _file:
        return toml.load(_file)

```

--------------------------------

### YAML Dumper for Configuration

Source: https://manderscience.com/typer-config/latest/api

The `yaml_dumper` function writes a configuration dictionary to a YAML file. It requires the `pyyaml` library. If `pyyaml` is not installed, it raises a `ModuleNotFoundError`. The function takes the configuration and the output file path, opening the file in write mode with UTF-8 encoding.

```python
def yaml_dumper(config: ConfigDict, location: FilePath) -> None:
    """Dump config to YAML file.

    Args:
        config (ConfigDict): configuration
        location (FilePath): file to write

    Raises:
        ModuleNotFoundError: pyyaml is required
    """

    yaml = try_import("yaml")

    if yaml is None:  # pragma: no cover
        message = "Please install the pyyaml library."
        raise ModuleNotFoundError(message)

    with open(location, "w", encoding="utf-8") as _file:
        yaml.dump(config, _file)
```

--------------------------------

### Typer App with YAML Config (Python)

Source: https://manderscience.com/typer-config/latest/examples/simple_yaml

A simple Typer application that utilizes the `use_yaml_config` decorator to load configuration options from a YAML file. It defines command-line arguments and options that can be overridden by the configuration file.

```python
from typing_extensions import Annotated

import typer
from typer_config.decorators import use_yaml_config  # other formats available 

app = typer.Typer()


@app.command()
@use_yaml_config()
def main(
    arg1: str,
    opt1: Annotated[str, typer.Option()],
    opt2: Annotated[str, typer.Option()] = "hello",
):
    typer.echo(f"{opt1} {opt2} {arg1}")


if __name__ == "__main__":
    app()

```

--------------------------------

### Load Dotenv Configuration with dotenv_loader

Source: https://manderscience.com/typer-config/latest/api

The dotenv_loader function parses a Dotenv file (.env) into a ConfigDict. It depends on the 'python-dotenv' library. If this library is not installed, a ModuleNotFoundError is raised.

```python
def dotenv_loader(param_value: TyperParameterValue) -> ConfigDict:
    """Dotenv file loader.

    Args:
        param_value (TyperParameterValue): path of Dotenv file

    Raises:
        ModuleNotFoundError: python-dotenv library is not installed

    Returns:
        ConfigDict: dictionary loaded from file
    """

    dotenv = try_import("dotenv")

    if dotenv is None:  # pragma: no cover
        message = "Please install the python-dotenv library."
        raise ModuleNotFoundError(message)

    with open(param_value, "r", encoding="utf-8") as _file:
        # NOTE: I'm using a stream here so that the loader
        # will raise an exception when the file doesn't exist.
        conf: ConfigDict = dotenv.dotenv_values(stream=_file)

    return conf

```

--------------------------------

### Get Dictionary Section Utility

Source: https://manderscience.com/typer-config/latest/api

Retrieves a nested section from a dictionary based on a list of keys. If any key is not found, it defaults to an empty dictionary, preventing errors.

```python
from typing import Dict, Any, Optional, List

def get_dict_section(
    _dict: Dict[Any, Any], keys: Optional[List[Any]] = None
) -> Dict[Any, Any]:
    """Get section of a dictionary.

    Args:
        _dict (Dict[str, Any]): dictionary to access
        keys (List[str]): list of keys to successively access in the dictionary

    Returns:
        Dict[str, Any]: section of dictionary requested
    """
    if keys is not None:
        for key in keys:
            _dict = _dict.get(key, {})

    return _dict

```

--------------------------------

### Load YAML Configuration with yaml_loader

Source: https://manderscience.com/typer-config/latest/api

The yaml_loader function reads a YAML file and parses its content into a ConfigDict. It requires the 'pyyaml' library to be installed. If the library is not found, it raises a ModuleNotFoundError.

```python
def yaml_loader(param_value: TyperParameterValue) -> ConfigDict:
    """YAML file loader.

    Args:
        param_value (TyperParameterValue): path of YAML file

    Raises:
        ModuleNotFoundError: pyyaml library is not installed

    Returns:
        ConfigDict: dictionary loaded from file
    """

    yaml = try_import("yaml")

    if yaml is None:  # pragma: no cover
        message = "Please install the pyyaml library."
        raise ModuleNotFoundError(message)

    with open(param_value, "r", encoding="utf-8") as _file:
        conf: ConfigDict = yaml.safe_load(_file)

    return conf

```

--------------------------------

### Using `is_eager=True` for Config Parameters in Typer

Source: https://manderscience.com/typer-config/latest/how

Demonstrates how to define a configuration parameter with `is_eager=True` to ensure it is processed first. This is crucial when directly using the `config` parameter in your Typer application to avoid unpredictable parameter values.

```python
config: str = typer.Option("", is_eager=True, callback=...)
```

--------------------------------

### use_config Decorator

Source: https://manderscience.com/typer-config/latest/api

The `use_config` decorator allows you to easily integrate configuration loading into your Typer commands. It accepts a callback function to handle the configuration loading process and allows customization of the parameter name and help text.

```APIDOC
## use_config Decorator

### Description
Decorator for using configuration on a typer command.

### Method
DECORATOR

### Endpoint
N/A (Decorator)

### Parameters
#### Arguments
- **callback** (ConfigParameterCallback) - Required - config parameter callback to load
- **param_name** (TyperParameterName) - Optional - name of config parameter. Defaults to "config".
- **param_help** (str) - Optional - config parameter help string. Defaults to "Configuration file.".

### Request Example
```python
import typer
from typer_config.decorators import use_config
from typer_config import yaml_conf_callback

app = typer.Typer()

@app.command()
@use_config(yaml_conf_callback)
def main(...):
    pass
```

### Response
#### Success Response
- **TyperCommandDecorator** (TyperCommandDecorator) - decorator to apply to command
```

--------------------------------

### JSON File Loader

Source: https://manderscience.com/typer-config/latest/api

Loads configuration data from a JSON file. This function parses the JSON content into a dictionary.

```APIDOC
## json_loader

### Description
JSON file loader. Parses the JSON content of a file into a configuration dictionary.

### Method
N/A (Function)

### Endpoint
N/A (Function)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```python
# config = json_loader("path/to/your/config.json")
```

### Response
#### Success Response (200)
- **ConfigDict** (`ConfigDict`) - dictionary loaded from file

#### Response Example
```json
{
  "key1": "value1",
  "key2": {
    "nested_key": "nested_value"
  }
}
```
```

--------------------------------

### File Existence Check and Warning

Source: https://manderscience.com/typer-config/latest/api

Checks if a file exists at the given path. If the file does not exist, it issues a warning using a simple format. Returns a boolean indicating the file's existence.

```python
from pathlib import Path
from typing import Union
from warnings import showwarning

# Assuming SimpleWarningFormat and ORIGINAL_WARNING_FORMATTER are defined elsewhere
# For this standalone snippet, we'll include them:

ORIGINAL_WARNING_FORMATTER = warnings.formatwarning

class SimpleWarningFormat:
    """Simple Warning Formatter."""
    def __enter__(self) -> None:
        warnings.formatwarning = lambda msg, category, *args, **kwargs: f"{category.__name__}: {msg}\n"
    def __exit__(self, exc_type, exc_value, exc_tb) -> None:
        warnings.formatwarning = ORIGINAL_WARNING_FORMATTER

def file_exists_and_warn(file_path: Union[Path, str]) -> bool:
    """Check if file exists and warn if it doesn't exist.

    Args:
        file_path (Union[Path, str]): file path to check

    Returns:
        bool: whether file exists
    """

    file_path_exists = Path(file_path).is_file()

    if not file_path_exists:
        msg = f"No such file: '{file_path}'"

        with SimpleWarningFormat():
            showwarning(msg, UserWarning, "", 0)

    return file_path_exists

```

--------------------------------

### Load JSON Configuration File

Source: https://manderscience.com/typer-config/latest/api

Loads configuration from a JSON file into a ConfigDict. This function takes the path to the JSON file as input. It directly parses the JSON content and returns it as a dictionary. No external libraries beyond standard Python are required for this loader.

```python
def json_loader(param_value: TyperParameterValue) -> ConfigDict:
    """JSON file loader.

    Args:
        param_value (TyperParameterValue): path of JSON file

    Returns:
        ConfigDict: dictionary loaded from file
    """

    with open(param_value, "r", encoding="utf-8") as _file:
        conf: ConfigDict = json.load(_file)

    return conf

```

--------------------------------

### file_exists_and_warn

Source: https://manderscience.com/typer-config/latest/api

Checks if a given file path exists. If the file does not exist, it issues a warning to the user.

```APIDOC
## file_exists_and_warn

### Description
Check if file exists and warn if it doesn't exist.

### Method
*Not applicable (function signature provided)*

### Endpoint
*Not applicable (function signature provided)*

### Parameters
#### Path Parameters
*None*

#### Query Parameters
*None*

#### Request Body
*None*

### Request Example
*Not applicable (function signature provided)*

### Response
#### Success Response (200)
*Not applicable (function signature provided)*

#### Response Example
*Not applicable (function signature provided)*

**Function Signature:**
```python
file_exists_and_warn(file_path: Union[Path, str]) -> bool
```

**Parameters:**
- `file_path` (Union[Path, str]) - Required - file path to check

**Returns:**
- `bool` (bool) - whether file exists
```

--------------------------------

### JSON Dumper for Configuration

Source: https://manderscience.com/typer-config/latest/api

The `json_dumper` function is responsible for writing a configuration dictionary to a JSON file. It takes the configuration as a `ConfigDict` and the output file path as arguments. It opens the file in write mode with UTF-8 encoding.

```python
def json_dumper(config: ConfigDict, location: FilePath) -> None:
    """Dump config to JSON file.

    Args:
        config (ConfigDict): configuration
        location (FilePath): file to write
    """
    with open(location, "w", encoding="utf-8") as _file:
        json.dump(config, _file)
```

--------------------------------

### Dump YAML Config Decorator for Typer Commands

Source: https://manderscience.com/typer-config/latest/api

The `dump_yaml_config` decorator is used with Typer commands to automatically save invocation parameters to a YAML file. It requires the `pyyaml` library to be installed. The decorator takes the file path as an argument and must be placed after the `@app.command()` decorator.

```python
def dump_yaml_config(location: FilePath) -> TyperCommandDecorator:
    """Decorator for dumping a YAML file with parameters
    from an invocation of a typer command.

    Usage:
        ```py
        import typer
        from typer.decorators import dump_yaml_config

        app = typer.Typer()

        @app.command()
        # NOTE: @dump_yaml_config MUST BE AFTER @app.command()
        @dump_yaml_config("config_dump_dir/params.yml")
        def cmd(...):
            ...
        ```

    Args:
        location (FilePath): config file to write

    Returns:
        TyperCommandDecorator: command decorator
    """
    return dump_config(dumper=yaml_dumper, location=location)
```

--------------------------------

### Python Typer App with YAML Schema Validation

Source: https://manderscience.com/typer-config/latest/examples/schema

This Python script defines a Typer application that accepts a configuration file. It uses a schema to validate the contents of the YAML configuration file loaded via `yaml_loader` and `conf_callback_factory`. The `use_config` decorator applies the custom configuration callback.

```python
from typing import Any, Dict
from typing_extensions import Annotated

from schema import Schema
import typer
from typer_config import yaml_loader, conf_callback_factory, use_config

schema = Schema({"arg1": str, "opt1": str, "opt2": str})


def validator_loader(param_value: str) -> Dict[str, Any]:
    conf = yaml_loader(param_value)
    conf = schema.validate(conf)  # raises an exception if not valid
    return conf


validator_callback = conf_callback_factory(validator_loader)

app = typer.Typer()


@app.command()
@use_config(validator_callback)
def main(
    arg1: str,
    opt1: Annotated[str, typer.Option()],
    opt2: Annotated[str, typer.Option()] = "hello",
):
    typer.echo(f"{opt1} {opt2} {arg1}")


if __name__ == "__main__":
    app()

```

--------------------------------

### use_dotenv_config Decorator

Source: https://manderscience.com/typer-config/latest/api

This decorator allows you to easily load configuration from a .env file for your Typer commands. It handles parameter creation, loading, and transformation of the configuration data.

```APIDOC
## use_dotenv_config Decorator

### Description
Decorator for using dotenv configuration on a typer command. It simplifies the process of loading configuration from `.env` files into your Typer application.

### Method
Decorator

### Endpoint
N/A (Decorator)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```python
import typer
from typer_config.decorators import use_dotenv_config

app = typer.Typer()

@app.command()
@use_dotenv_config(section=['database'], param_name='db_config')
def main(db_config: dict = typer.Option(...)):
    print(f"Database config: {db_config}")

if __name__ == '__main__':
    app()
```

### Response
#### Success Response (200)
N/A (Decorator)

#### Response Example
N/A (Decorator)
```

--------------------------------

### Python Pydantic and Typer App with YAML Config Validation

Source: https://manderscience.com/typer-config/latest/examples/pydantic

A Python script using Typer and Pydantic to load and validate application configuration from a YAML file. It defines a Pydantic BaseModel for configuration structure and uses a custom callback factory to perform validation before the application logic executes. Dependencies include 'typer', 'pydantic', and 'typer-config'.

```python
from typing import Any, Dict
from typing_extensions import Annotated

from pydantic import BaseModel
import typer
from typer_config.loaders import yaml_loader
from typer_config.callbacks import conf_callback_factory
from typer_config.decorators import use_config


class AppConfig(BaseModel):
    arg1: str
    opt1: str
    opt2: str


def validator_loader(param_value: str) -> Dict[str, Any]:
    conf = yaml_loader(param_value)
    AppConfig.validate(conf)  # raises an exception if not valid
    return conf


validator_callback = conf_callback_factory(validator_loader)

app = typer.Typer()


@app.command()
@use_config(validator_callback)
def main(
    arg1: str,
    opt1: Annotated[str, typer.Option()],
    opt2: Annotated[str, typer.Option()] = "hello",
):
    typer.echo(f"{opt1} {opt2} {arg1}")


if __name__ == "__main__":
    app()

```

--------------------------------

### Simple Warning Formatter Context Manager

Source: https://manderscience.com/typer-config/latest/api

A context manager that temporarily overrides the default warning formatter to provide a simpler format. It restores the original formatter upon exiting the context.

```python
import warnings
from typing import Any

ORIGINAL_WARNING_FORMATTER = warnings.formatwarning

class SimpleWarningFormat:
    """Simple Warning Formatter."""

    def __enter__(self: SimpleWarningFormat) -> None:  # noqa: D105
        warnings.formatwarning = (
            lambda msg, category, *args, **kwargs: f"{category.__name__}: {msg}\n"  # noqa: ARG005
        )

    def __exit__(
        self: SimpleWarningFormat,
        exc_type: Any,  # noqa: ANN401
        exc_value: Any,  # noqa: ANN401
        exc_tb: Any,  # noqa: ANN401
    ) -> None:
        warnings.formatwarning = ORIGINAL_WARNING_FORMATTER

```

--------------------------------

### Dotenv Configuration Callback

Source: https://manderscience.com/typer-config/latest/api

Provides a callback function for Typer to load configuration from .env files. It uses a factory to create a callback that transforms loaded environment variables.

```APIDOC
## dotenv_conf_callback

### Description
Dotenv typer config parameter callback.

### Method
N/A (This is a callback function definition)

### Endpoint
N/A

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```python
# This is a callback, not directly invoked with a request body.
# Example usage within a Typer app would involve defining a parameter
# that uses this callback.
```

### Response
#### Success Response (N/A)
N/A

#### Response Example
```json
{
  "message": "Configuration loaded from .env file"
}
```

### Raises
- **BadParameter**: bad parameter value
```

--------------------------------

### JSON Configuration Callback

Source: https://manderscience.com/typer-config/latest/api

Offers a callback function for Typer to load configuration from JSON files. It wraps a JSON loader with transformation capabilities.

```APIDOC
## json_conf_callback

### Description
JSON typer config parameter callback.

### Method
N/A (This is a callback function definition)

### Endpoint
N/A

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```python
# This is a callback, not directly invoked with a request body.
# Example usage within a Typer app would involve defining a parameter
# that uses this callback.
```

### Response
#### Success Response (N/A)
N/A

#### Response Example
```json
{
  "message": "Configuration loaded from JSON file"
}
```

### Raises
- **BadParameter**: bad parameter value
```

--------------------------------

### TOML Configuration Callback

Source: https://manderscience.com/typer-config/latest/api

Provides a callback function for Typer to load configuration from TOML files. It utilizes a factory and loader transformer for TOML data.

```APIDOC
## toml_conf_callback

### Description
TOML typer config parameter callback.

### Method
N/A (This is a callback function definition)

### Endpoint
N/A

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```python
# This is a callback, not directly invoked with a request body.
# Example usage within a Typer app would involve defining a parameter
# that uses this callback.
```

### Response
#### Success Response (N/A)
N/A

#### Response Example
```json
{
  "message": "Configuration loaded from TOML file"
}
```

### Raises
- **BadParameter**: bad parameter value
```

--------------------------------

### Use Configuration Decorator for Typer Commands (Python)

Source: https://manderscience.com/typer-config/latest/api

The `use_config` decorator is applied to Typer commands to automatically load configuration from a file. It requires a callback function to process the configuration and can be customized with parameter name and help text. This decorator modifies the command's signature to include the configuration parameter.

```python
from typing import Callable, Any
from inspect import signature, Parameter
from functools import wraps

from typer import TyperCommand, Option

# Assuming these types are defined elsewhere in the library
TyperParameterName = str
ConfigParameterCallback = Callable[[str], Any]
TyperCommandDecorator = Callable[[TyperCommand], TyperCommand]

def use_config(
    callback: ConfigParameterCallback,
    param_name: TyperParameterName = "config",
    param_help: str = "Configuration file.",
) -> TyperCommandDecorator:
    """Decorator for using configuration on a typer command.

    Usage:
        ```py
        import typer
        from typer_config.decorators import use_config
        from typer_config import yaml_conf_callback # whichever callback to use

        app = typer.Typer()

        @app.command()
        @use_config(yaml_conf_callback)
        def main(...):
            pass # ... command logic
        ```

    Args:
        callback (ConfigParameterCallback): config parameter callback to load
        param_name (TyperParameterName, optional): name of config parameter.
            Defaults to "config".
        param_help (str, optional): config parameter help string.
            Defaults to "Configuration file.".

    Returns:
        TyperCommandDecorator: decorator to apply to command
    """

    def decorator(cmd: TyperCommand) -> TyperCommand:
        # NOTE: modifying a function's __signature__ is dangerous
        # in the sense that it only affects inspect.signature().
        # It does not affect the actual function implementation.
        # So, a caller can be confused how to pass parameters to
        # the function with modified signature.
        sig = signature(cmd, eval_str=True)

        config_param = Parameter(
            param_name,
            kind=Parameter.KEYWORD_ONLY,
            annotation=str,
            default=Option("", callback=callback, is_eager=True, help=param_help),
        )

        new_sig = sig.replace(parameters=[*sig.parameters.values(), config_param])

        @wraps(cmd)
        def wrapped(*args, **kwargs):  # noqa: ANN20,ANN002,ANN003
            # NOTE: need to delete the config parameter
            # to match the wrapped command's signature.
            kwargs.pop(param_name, None)

            return cmd(*args, **kwargs)

        wrapped.__signature__ = new_sig  # type: ignore

        return wrapped

    return decorator

```

--------------------------------

### Load INI Configuration File

Source: https://manderscience.com/typer-config/latest/api

Loads configuration from an INI file into a ConfigDict. INI files require top-level sections. This loader is often combined with `loader_transformer` to extract specific sections from the loaded configuration. It takes the path to the INI file as input and returns a dictionary representing the file's content.

```python
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 `loader_transformer`
        to extract the correct section.
        For example:
        ```py
        ini_section_loader = loader_transformer(
            ini_loader,
            config_transformer=lambda config: config["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

```

--------------------------------

### SimpleWarningFormat

Source: https://manderscience.com/typer-config/latest/api

A context manager that temporarily changes the global warning format to a simpler one, useful for custom warning messages.

```APIDOC
## SimpleWarningFormat

### Description
Simple Warning Formatter.

### Method
*Not applicable (class definition provided)*

### Endpoint
*Not applicable (class definition provided)*

### Parameters
*None*

### Request Example
*None*

### Response
*None*

**Class Definition:**
```python
class SimpleWarningFormat:
    """Simple Warning Formatter."""

    def __enter__(self: SimpleWarningFormat) -> None:
        warnings.formatwarning = (
            lambda msg, category, *args, **kwargs: f"{category.__name__}: {msg}\n" 
        )

    def __exit__(
        self: SimpleWarningFormat,
        exc_type: Any, 
        exc_value: Any,
        exc_tb: Any,
    ) -> None:
        warnings.formatwarning = ORIGINAL_WARNING_FORMATTER
```
```

--------------------------------

### conf_callback_factory

Source: https://manderscience.com/typer-config/latest/api

Creates a Typer configuration callback function. This factory allows you to define how configuration files are loaded and merged into the Typer CLI's default context.

```APIDOC
## conf_callback_factory

### Description
Typer configuration callback factory. This function creates a callback that loads configuration from a specified loader and updates the Click context's default map.

### Method
Factory Function

### Endpoint
N/A (This is a Python function, not an HTTP endpoint)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None (This is a Python function signature)

### Request Example
```python
from typer_config import conf_callback_factory, ConfigLoader
from typer import Typer, Context, CallbackParam

def my_config_loader(value: str) -> dict:
    # Implement your config loading logic here
    # For example, load from a file based on the value
    if value == "prod":
        return {"database_url": "postgres://prod_user@host/prod_db"}
    return {"database_url": "postgres://dev_user@host/dev_db"}

callback = conf_callback_factory(loader=my_config_loader)

# Example usage within a Typer app (simplified)
def main(config_env: str = typer.Option(..., callback=callback)):
    print(f"Config environment: {config_env}")

if __name__ == "__main__":
    from typer import Typer
    app = Typer()
    app.command()(main)
    app([]) # Example call, in real use it would be `app(['--config-env', 'prod'])`
```

### Response
#### Success Response (200)
Returns a `ConfigParameterCallback` function.

#### Response Example
```python
# The returned value is a callable function, not a direct JSON response.
def config_parameter_callback(ctx: Context, param: CallbackParam, param_value: str):
    # ... internal logic ...
    return param_value
```
```

--------------------------------

### YAML Configuration Callback

Source: https://manderscience.com/typer-config/latest/api

Offers a callback function for Typer to load configuration from YAML files. It integrates a YAML loader with conditional logic.

```APIDOC
## yaml_conf_callback

### Description
YAML typer config parameter callback.

### Method
N/A (This is a callback function definition)

### Endpoint
N/A

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```python
# This is a callback, not directly invoked with a request body.
# Example usage within a Typer app would involve defining a parameter
# that uses this callback.
```

### Response
#### Success Response (N/A)
N/A

#### Response Example
```json
{
  "message": "Configuration loaded from YAML file"
}
```

### Raises
- **BadParameter**: bad parameter value
```

--------------------------------

### Create Typer Config Callback Factory (Python)

Source: https://manderscience.com/typer-config/latest/api

The conf_callback_factory is a Python function that generates a configuration parameter callback for Typer applications. It takes a ConfigLoader, which processes CLI arguments into a dictionary, and merges this dictionary into the Click context's default map. This function is crucial for enabling configuration loading from external sources into Typer applications.

```python
from typing import Dict, Any
from typer.models import CallbackParam
from click import Context
from typer.main import TyperParameterValue
from typer.exceptions import BadParameter


ConfigLoader = lambda param_value: Dict[str, Any]
ConfigParameterCallback = Any

def conf_callback_factory(loader: ConfigLoader) -> ConfigParameterCallback:
    """Typer configuration callback factory.

    Args:
        loader (ConfigLoader): Config loader function that takes the value
            passed to the typer CLI and returns a dictionary that is
            applied to the click context's default map.

    Returns:
        ConfigParameterCallback: Configuration parameter callback function.
    """

    def _callback(
        ctx: Context, param: CallbackParam, param_value: TyperParameterValue
    ) -> TyperParameterValue:
        """Generated typer config parameter callback.

        Args:
            ctx (typer.Context): typer context (automatically passed)
            param (typer.CallbackParam): typer callback parameter (automatically passed)
            param_value (TyperParameterValue): parameter value passed to typer
                (automatically passed)

        Raises:
            BadParameter: bad parameter value

        Returns:
            TyperParameterValue: must return back the given parameter
        """
        try:
            conf = loader(param_value)  # Load config file
            ctx.default_map = ctx.default_map or {}  # Initialize the default map
            ctx.default_map.update(conf)  # Merge the config Dict into default_map
        except Exception as ex:
            raise BadParameter(str(ex), ctx=ctx, param=param) from ex
        return param_value

    return _callback

```

--------------------------------

### Dump Configuration to JSON using Typer Decorator

Source: https://manderscience.com/typer-config/latest/api

The `dump_json_config` decorator simplifies the process of saving Typer command arguments to a JSON file. It leverages the `dump_config` function internally, using a predefined `json_dumper`. Similar to `dump_config`, this decorator must be placed after `@app.command()` and requires the file path for the output JSON.

```python
def dump_json_config(location: FilePath) -> TyperCommandDecorator:
    """Decorator for dumping a JSON file with parameters
    from an invocation of a typer command.

    Usage:
        ```py
        import typer
        from typer.decorators import dump_json_config

        app = typer.Typer()

        @app.command()
        # NOTE: @dump_json_config MUST BE AFTER @app.command()
        @dump_json_config("config_dump_dir/params.json")
        def cmd(...):
            ...
        ```

    Args:
        location (FilePath): config file to write

    Returns:
        TyperCommandDecorator: command decorator
    """
    return dump_config(dumper=json_dumper, location=location)

```

--------------------------------

### conf_callback_factory

Source: https://manderscience.com/typer-config/latest/api

Creates a configuration callback function for Typer CLI applications. This callback loads configuration values using a provided loader and updates the Click context's default map.

```APIDOC
## conf_callback_factory

### Description
Creates a configuration callback function for Typer CLI applications. This callback loads configuration values using a provided loader and updates the Click context's default map.

### Method
Factory Function

### Endpoint
N/A (This is a Python function, not a REST endpoint)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Request Example
```python
from typer import Typer, Context, CallbackParam
from typer.models import TyperParameterValue
from typing import Dict, Any

# Assume ConfigLoader and ConfigParameterCallback are defined elsewhere
ConfigLoader = Any
ConfigParameterCallback = Any

def conf_callback_factory(loader: ConfigLoader) -> ConfigParameterCallback:
    """Typer configuration callback factory."""
    def _callback(
        ctx: Context,
        param: CallbackParam,
        param_value: TyperParameterValue
    ) -> TyperParameterValue:
        try:
            conf = loader(param_value)
            ctx.default_map = ctx.default_map or {}
            ctx.default_map.update(conf)
        except Exception as ex:
            raise Exception(str(ex)) from ex # Simplified exception for example
        return param_value
    return _callback

# Example Usage:
def my_config_loader(value: str) -> Dict[str, Any]:
    # In a real scenario, this would load from a file based on 'value'
    if value == "dev":
        return {"database_url": "sqlite:///dev.db", "debug": True}
    return {} # Default empty config


config_callback = conf_callback_factory(my_config_loader)

# This 'config_callback' would then be used in a Typer application
# Example: app.add_option('--config', callback=config_callback)
```

### Response
#### Success Response (200)
N/A (This is a Python function, not a REST endpoint)

#### Response Example
N/A
```

--------------------------------

### Python Decorator for Typer Configuration Loading

Source: https://manderscience.com/typer-config/latest/api

The `use_config` decorator in `typer-config` is used to add configuration loading capabilities to Typer commands. It takes a callback function to handle configuration loading and optionally allows customization of the parameter name and help string. This decorator modifies the command's signature to include the configuration parameter.

```python
from inspect import Parameter, signature
from functools import wraps

from typer import Option
from typer.models import TyperCommand

# Assuming these types are defined elsewhere in the library
# from .callback import ConfigParameterCallback
# from .typing import TyperParameterName
# from .decorators import TyperCommandDecorator

# Placeholder types for demonstration purposes
class ConfigParameterCallback:
    pass

class TyperParameterName(str):
    pass

class TyperCommandDecorator(object):
    pass

def use_config(
    callback: ConfigParameterCallback,
    param_name: TyperParameterName = "config",
    param_help: str = "Configuration file.",
) -> TyperCommandDecorator:
    """Decorator for using configuration on a typer command.

    Usage:
        ```py
        import typer
        from typer_config.decorators import use_config
        from typer_config import yaml_conf_callback # whichever callback to use

        app = typer.Typer()

        @app.command()
        @use_config(yaml_conf_callback)
        def main(...):
            ...
        ```

    Args:
        callback (ConfigParameterCallback): config parameter callback to load
        param_name (TyperParameterName, optional): name of config parameter.
            Defaults to "config".
        param_help (str, optional): config parameter help string.
            Defaults to "Configuration file.".

    Returns:
        TyperCommandDecorator: decorator to apply to command
    """

    def decorator(cmd: TyperCommand) -> TyperCommand:
        # NOTE: modifying a function's __signature__ is dangerous
        # in the sense that it only affects inspect.signature().
        # It does not affect the actual function implementation.
        # So, a caller can be confused how to pass parameters to
        # the function with modified signature.
        sig = signature(cmd, eval_str=True)

        config_param = Parameter(
            param_name,
            kind=Parameter.KEYWORD_ONLY,
            annotation=str,
            default=Option("", callback=callback, is_eager=True, help=param_help),
        )

        new_sig = sig.replace(parameters=[*sig.parameters.values(), config_param])

        @wraps(cmd)
        def wrapped(*args, **kwargs):  # noqa: ANN20,ANN002,ANN003
            # NOTE: need to delete the config parameter
            # to match the wrapped command's signature.
            kwargs.pop(param_name, None)

            return cmd(*args, **kwargs)

        wrapped.__signature__ = new_sig  # type: ignore

        return wrapped

    return decorator

```
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