feat: create app for diffpy.cmi CLI

news/app-creation.rst

@@ -0,0 +1,23 @@
+**Added:**
+
+* Add CLI to return diffpy.cmi version and help page.
+
+**Changed:**
+
+* <news item>
+
+**Deprecated:**
+
+* <news item>
+
+**Removed:**
+
+* <news item>
+
+**Fixed:**
+
+* <news item>
+
+**Security:**
+
+* <news item>

pyproject.toml

@@ -48,6 +48,9 @@ include = ["*"]  # package names should match these glob patterns (["*"] by defa
 exclude = []  # exclude packages matching these glob patterns (empty by default)
 namespaces = false  # to disable scanning PEP 420 namespaces (true by default)
 
+[project.scripts]
+diffpy-cmi = "diffpy.cmi.app:main"
+
 [tool.setuptools.dynamic]
 dependencies = {file = ["requirements/pip.txt"]}
 

src/diffpy/cmi/__init__.py

@@ -12,7 +12,8 @@
 # See LICENSE.rst for license information.
 #
 ##############################################################################
-"""Complex modeling infrastructure: a modulare framework for multi-modal modeling of scientific data."""
+"""Complex modeling infrastructure:
+a modulare framework for multi-modal modeling of scientific data."""
 
 # package version
 from diffpy.cmi.version import __version__  # noqa

src/diffpy/cmi/app.py

@@ -0,0 +1,58 @@
+import getopt
+import sys
+
+from diffpy.cmi.version import __version__
+
+
+def usage():
+    """Print short help message."""
+    print(
+        """\
+
+Welcome to diffpy-CMI, a complex modeling infrastructure
+designed for multi-modal analysis of scientific data.
+While broadly applicable to a wide range of problems,
+including those beyond materials science, diffpy-CMI currently
+provides robust tools for modeling atomic structure based on
+Pair Distribution Function (PDF) and Small-Angle Scattering (SAS) data.
+Its modular Python architecture enables extensible workflows,
+with additional capabilities continually being developed.
+
+Docs: https://www.diffpy.org/diffpy.cmi
+
+Usage:
+    diffpy-cmi [--version] [--help]
+
+Options:
+    -V, --version     Show version and exit
+    -h, --help        Show this message and exit
+"""
+    )
+
+
+def version():
+    print(f"diffpy-cmi {__version__}")
+
+
+def main():
+    try:
+        opts, args = getopt.gnu_getopt(sys.argv[1:], "hV", ["help", "version"])
+    except getopt.GetoptError as err:
+        print(f"Error: {err}", file=sys.stderr)
+        usage()
+        sys.exit(1)
+
+    for opt, _ in opts:
+        if opt in ("-h", "--help"):
+            usage()
+            return
+        elif opt in ("-V", "--version"):
+            version()
+            return
+
+    # Default behavior (if no arguments)
+    usage()
+
+
+if __name__ == "__main__":
+    main()