Resolve "Add a command-line interface"

.github/dependabot.yaml

@@ -4,7 +4,13 @@ updates:
     directory: "/"
     schedule:
       interval: "weekly"
+    reviewers:
+      - "btschwertfeger"
   - package-ecosystem: "pip"
     directory: "/"
     schedule:
       interval: "weekly"
+    reviewers:
+      - "btschwertfeger"
+    ignore:
+      - dependency-name: "ruff"

.github/workflows/_codecov.yaml

@@ -45,7 +45,7 @@ jobs:
         run: python -m pip install --upgrade pip
 
       - name: Install package
-        run: python -m pip install ".[dev]"
+        run: python -m pip install ".[dev,test]"
 
       - name: Generate coverage report
         run: pytest --cov --cov-report=xml

.github/workflows/_test.yaml

@@ -37,7 +37,7 @@ jobs:
           python -m pip install --upgrade pip
 
       - name: Install package
-        run: python -m pip install ".[dev]"
+        run: python -m pip install ".[dev,test]"
 
       - name: Run unit tests
         run: pytest -vv tests

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.2.2
+    rev: v0.3.5
     hooks:
       - id: ruff
         args:

Makefile

@@ -24,7 +24,7 @@ build:
 .PHONY: dev
 dev:
 	@git lfs install
-	$(PYTHON) -m pip install -e ".[dev]"
+	$(PYTHON) -m pip install -e ".[dev,test]"
 
 ## install		Install the package
 ##

README.md

@@ -24,7 +24,7 @@ Welcome to python-cmethods, a powerful Python package designed for bias
 correction and adjustment of climate data. Built with a focus on ease of use and
 efficiency, python-cmethods offers a comprehensive suite of functions tailored
 for applying bias correction methods to climate model simulations and
-observational datasets.
+observational datasets via command-line interface and API.
 
 Please cite this project as described in
 https://zenodo.org/doi/10.5281/zenodo.7652755.
@@ -143,7 +143,64 @@ python3 -m pip install python-cmethods
 
 <a name="examples"></a>
 
-## 4. Usage and Examples
+## 4. CLI Usage
+
+The python-cmethods package provides a command-line interface for applying
+various bias correction methods out of the box.
+
+Keep in mind that due to the various kinds of data and possibilities to
+pre-process those, the CLI only provides a basic application of the implemented
+techniques. For special parameters, adjustments, and data preparation, please
+use programming interface.
+
+Listing the parameters and their requirements is available by passing the
+`--help` option:
+
+```bash
+cmethods --help
+```
+
+Applying the cmethods tool on the provided example data using the linear scaling
+approach is shown below:
+
+```bash
+cmethods \
+  --obs examples/input_data/observations.nc \
+  --simh examples/input_data/control.nc \
+  --simp examples/input_data/scenario.nc \
+  --method linear_scaling \
+  --kind add \
+  --variable tas \
+  --group time.month \
+  --output linear_scaling.nc
+
+2024/04/08 18:11:12     INFO | Loading data sets ...
+2024/04/08 18:11:12     INFO | Data sets loaded ...
+2024/04/08 18:11:12     INFO | Applying linear_scaling ...
+2024/04/08 18:11:15     INFO | Saving result to linear_scaling.nc ...
+```
+
+For applying a distribution-based bias correction technique, the following
+example may help:
+
+```bash
+cmethods \
+  --obs examples/input_data/observations.nc \
+  --simh examples/input_data/control.nc \
+  --simp examples/input_data/scenario.nc \
+  --method quantile_delta_mapping \
+  --kind add \
+  --variable tas \
+  --quantiles 1000 \
+  --output quantile_delta_mapping.nc
+
+2024/04/08 18:16:34     INFO | Loading data sets ...
+2024/04/08 18:16:35     INFO | Data sets loaded ...
+2024/04/08 18:16:35     INFO | Applying quantile_delta_mapping ...
+2024/04/08 18:16:35     INFO | Saving result to quantile_delta_mapping.nc ...
+```
+
+## 5. Programming Interface Usage and Examples
 
 ```python
 import xarray as xr

cmethods/__init__.py

@@ -3,6 +3,7 @@
 # Copyright (C) 2023 Benjamin Thomas Schwertfeger
 # GitHub: https://github.com/btschwertfeger
 #
+# pylint: disable=consider-using-f-string,logging-not-lazy
 
 r"""
     Module providing the a method named "adjust" to apply different bias
@@ -24,12 +25,170 @@
     _{m} = long-term monthly interval
 """
 
-from cmethods.core import adjust
+from __future__ import annotations
+
+import logging
+import sys
 
-__author__ = "Benjamin Thomas Schwertfeger"
-__copyright__ = __author__
-__email__ = "contact@b-schwertfeger.de"
-__link__ = "https://github.com/btschwertfeger"
-__github__ = "https://github.com/btschwertfeger/python-cmethods"
+import cloup
+import xarray as xr
+from cloup import (
+    HelpFormatter,
+    HelpTheme,
+    Path,
+    Style,
+    command,
+    option,
+    option_group,
+    version_option,
+)
+from cloup.constraints import Equal, If, require_all
+
+from cmethods.core import adjust
 
 __all__ = ["adjust"]
+
+
+@command(
+    context_settings={
+        "auto_envvar_prefix": "CMETHODS",
+        "help_option_names": ["-h", "--help"],
+    },
+    formatter_settings=HelpFormatter.settings(
+        theme=HelpTheme(
+            invoked_command=Style(fg="bright_yellow"),
+            heading=Style(fg="bright_white", bold=True),
+            constraint=Style(fg="magenta"),
+            col1=Style(fg="bright_yellow"),
+        ),
+    ),
+)
+@version_option(message="%version%")
+@option(
+    "--obs",
+    "--observations",
+    required=True,
+    type=Path(exists=True),
+    help="Reference data set (control period)",
+)
+@option(
+    "--simh",
+    "--simulated-historical",
+    required=True,
+    type=Path(exists=True),
+    help="Modeled data set (control period)",
+)
+@option(
+    "--simp",
+    "--simulated-scenario",
+    required=True,
+    type=Path(exists=True),
+    help="Modeled data set (scenario period)",
+)
+@option(
+    "--method",
+    required=True,
+    type=cloup.Choice(
+        [
+            "linear_scaling",
+            "variance_scaling",
+            "delta_method",
+            "quantile_mapping",
+            "quantile_delta_mapping",
+        ],
+        case_sensitive=False,
+    ),
+    help="Bias adjustment method to apply",
+)
+@option(
+    "--kind",
+    required=True,
+    type=cloup.Choice(["+", "add", "*", "mult"]),
+    help="Kind of adjustment",
+)
+@option(
+    "--variable",
+    required=True,
+    type=str,
+    help="Variable of interest",
+)
+@option(
+    "-o",
+    "--output",
+    required=True,
+    type=str,
+    callback=lambda _, __, value: (value if value.endswith(".nc") else f"{value}.nc"),
+    help="Output file name",
+)
+@option_group(
+    "Scaling-Based Adjustment Options",
+    option(
+        "--group",
+        type=str,
+        help="Temporal grouping",
+    ),
+    constraint=If(
+        Equal("method", "linear_scaling")
+        & Equal("method", "variance_scaling")
+        & Equal("method", "delta_method"),
+        then=require_all,
+    ),
+)
+@option_group(
+    "Distribution-Based Adjustment Options",
+    option(
+        "--quantiles",
+        type=int,
+        help="Quantiles to respect",
+    ),
+    constraint=If(
+        Equal("method", "quantile_mapping") & Equal("method", "quantile_delta_mapping"),
+        then=require_all,
+    ),
+)
+def cli(**kwargs) -> None:
+    """
+    Command-line tool to apply bias correction procedures to climate data.
+
+    Copyright (C) 2023 Benjamin Thomas Schwertfeger\n
+    GitHub: https://github.com/btschwertfeger/python-cmethods
+    """
+
+    logging.basicConfig(
+        format="%(asctime)s %(levelname)8s | %(message)s",
+        datefmt="%Y/%m/%d %H:%M:%S",
+        level=logging.INFO,
+    )
+
+    logging.info("Loading data sets ...")
+    try:
+        for key, message in zip(
+            ("obs", "simh", "simp"),
+            (
+                "observation data set",
+                "modeled data set of the control period",
+                "modeled data set of the scenario period",
+            ),
+        ):
+            kwargs[key] = xr.open_dataset(kwargs[key])
+            if not isinstance(kwargs[key], xr.Dataset):
+                raise TypeError("The data sets must be type xarray.Dataset")
+
+            if kwargs["variable"] not in kwargs[key]:
+                raise KeyError(
+                    f"Variable '{kwargs['variable']}' is missing in the {message}",
+                )
+            kwargs[key] = kwargs[key][kwargs["variable"]]
+    except (TypeError, KeyError) as exc:
+        logging.error(exc)
+        sys.exit(1)
+
+    logging.info("Data sets loaded ...")
+    kwargs["n_quantiles"] = kwargs["quantiles"]
+    del kwargs["quantiles"]
+
+    logging.info("Applying %s ..." % kwargs["method"])
+    result = adjust(**kwargs)
+
+    logging.info("Saving result to %s ..." % kwargs["output"])
+    result.to_netcdf(kwargs["output"])

doc/cli.rst

@@ -0,0 +1,41 @@
+.. -*- coding: utf-8 -*-
+.. Copyright (C) 2023 Benjamin Thomas Schwertfeger
+.. GitHub: https://github.com/btschwertfeger
+..
+
+Command-Line Interface
+======================
+
+The command-line interface provides the following help instructions
+
+.. code-block:: bash
+
+    cmethods --help
+
+    Usage: cmethods [OPTIONS]
+
+      Command line tool to apply bias adjustment procedures to climate data.
+
+    Scaling-Based Adjustment Options:
+      [all required if --method="linear_scaling" and --method="variance_scaling" and
+      --method="delta_method"]
+      --group TEXT                Temporal grouping
+
+    Distribution-Based Adjustment Options:
+      [all required if --method="quantile_mapping" and
+      --method="quantile_delta_mapping"]
+      --quantiles INTEGER         Quantiles to respect
+
+    Other options:
+      --version                   Show the version and exit.
+      --obs, --observations PATH  Reference data set (control period)  [required]
+      --simh, --simulated-historical PATH
+                                Modeled data set (control period)  [required]
+      --simp, --simulated-scenario PATH
+                                Modeled data set (scenario period)  [required]
+      --method [linear_scaling|variance_scaling|delta_method|quantile_mapping|quantile_delta_mapping]
+                                Bias adjustment method to apply  [required]
+      --kind [add|mult]           Kind of adjustment  [required]
+      --variable TEXT             Variable of interest  [required]
+      -o, --output TEXT           Output file name  [required]
+      -h, --help                  Show this message and exit.

doc/cmethods.rst

@@ -1,3 +1,7 @@
+.. -*- coding: utf-8 -*-
+.. Copyright (C) 2023 Benjamin Thomas Schwertfeger
+.. GitHub: https://github.com/btschwertfeger
+..
 
 Classes and Functions
 =====================