Use entry points for subcommand discovery

.gitignore

@@ -26,3 +26,4 @@ tests/tmp*
 version.py
 tests/trivial_camera/qe_curves/ccd00/19700101T000000.ecsv
 tests/trivial_camera/qe_curves/ccd00/19800101T000000.ecsv
+python/*.dist-info/

pyproject.toml

@@ -1,3 +1,6 @@
+[project.entry-points.'butler.cli']
+obs_base = "lsst.obs.base.cli:get_cli_subcommands"
+
 [tool.towncrier]
     package = "lsst.obs.base"
     package_dir = "python"

python/lsst/obs/base/cli/__init__.py

@@ -0,0 +1 @@
+from ._get_cli_subcommands import get_cli_subcommands

python/lsst/obs/base/cli/_get_cli_subcommands.py

@@ -0,0 +1,37 @@
+# This file is part of obs_base.
+#
+# Developed for the LSST Data Management System.
+# This product includes software developed by the LSST Project
+# (http://www.lsst.org).
+# See the COPYRIGHT file at the top-level directory of this distribution
+# for details of code ownership.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+__all__ = ["get_cli_subcommands"]
+
+import click
+
+from . import cmd
+
+
+def get_cli_subcommands() -> list[click.Command]:
+    """Return the location of the CLI command plugin definitions.
+
+    Returns
+    -------
+    commands : `list` [ `click.Command` ]
+        The command-line subcommands provided by this package.
+    """
+    return [getattr(cmd, c) for c in cmd.__all__]

ups/obs_base.table

@@ -15,4 +15,3 @@ setupOptional(log)
 
 envPrepend(PYTHONPATH, ${PRODUCT_DIR}/python)
 envPrepend(PATH, ${PRODUCT_DIR}/bin)
-envPrepend(DAF_BUTLER_PLUGINS, ${PRODUCT_DIR}/python/lsst/obs/base/cli/resources.yaml)