Deprecate --gen2 flag.

doc/lsst.ap.verify/command-line-reference.rst

@@ -63,13 +63,17 @@ Required arguments are :option:`--dataset` and :option:`--output`.
    Specify data ID to process.
    If using :option:`--gen2`, this should use :doc:`data ID syntax </modules/lsst.pipe.base/command-line-task-dataid-howto>`, such as ``--data-query "visit=12345 ccd=1..6 filter=g"``.
    If using :option:`--gen3`, this should use :ref:`dimension expression syntax <daf_butler_dimension_expressions>`, such as ``--data-query "visit=12345 and detector in (1..6) and band='g'"``.
-   The ``-id`` form of this argument is for consistency with Gen 2 command-line tasks, and is deprecated.
 
    Multiple copies of this argument are allowed.
    For compatibility with the syntax used by command line tasks, this flag with no argument processes all data IDs.
 
    If this argument is omitted, then all data IDs in the dataset will be processed.
 
+   .. warning::
+
+      The ``--id`` form of this argument is for consistency with Gen 2 command-line tasks, and is deprecated.
+      It will be removed after Science Pipelines release 23.
+
 .. option:: --dataset <dataset_package>
 
    **Input dataset package.**
@@ -92,6 +96,10 @@ Required arguments are :option:`--dataset` and :option:`--output`.
    For the Gen 3 equivalent to this option, see :option:`--pipeline`.
    See also :doc:`new-metrics`.
 
+   .. warning::
+
+      Support for Gen 2 processing is deprecated and will be removed after Science Pipelines release 23.
+
 .. option:: --db, --db_url
 
    **Target Alert Production Database**
@@ -110,6 +118,10 @@ Required arguments are :option:`--dataset` and :option:`--output`.
    These optional flags run either the Gen 2 pipeline (`~lsst.ap.pipe.ApPipeTask`), or the Gen 3 pipeline (:file:`apPipe.yaml`).
    If neither flag is provided, the Gen 3 pipeline will be run.
 
+   .. warning::
+
+      Support for Gen 2 processing is deprecated and will be removed after Science Pipelines release 23.
+
 .. option:: -h, --help
 
    **Print help.**
@@ -134,6 +146,10 @@ Required arguments are :option:`--dataset` and :option:`--output`.
    For the Gen 3 equivalent to this option, see :option:`--pipeline`.
    See also :doc:`new-metrics`.
 
+   .. warning::
+
+      Support for Gen 2 processing is deprecated and will be removed after Science Pipelines release 23.
+
 .. option:: --metrics-file <filename>
 
    **Output metrics file. (Gen 2 only)**
@@ -142,6 +158,10 @@ Required arguments are :option:`--dataset` and :option:`--output`.
    The string ``{dataId}`` shall be replaced with the data ID associated with the job, and its use is strongly recommended.
    If omitted, the output will go to files named after ``ap_verify.{dataId}.verify.json`` in the user's working directory.
 
+   .. warning::
+
+      Support for Gen 2 processing is deprecated and will be removed after Science Pipelines release 23.
+
 .. option:: --output <workspace_dir>
 
    **Output and intermediate product path.**

python/lsst/ap/verify/ap_verify.py

@@ -31,6 +31,7 @@
 
 import argparse
 import re
+import warnings
 
 import lsst.log
 
@@ -91,6 +92,14 @@ def __init__(self):
             parents=[_InputOutputParser(), _ProcessingParser(), ApPipeParser(), MetricsParser()],
             add_help=True)
 
+    def parse_args(self, args=None, namespace=None):
+        namespace = super().parse_args(args, namespace)
+        # Code duplication; too hard to implement at shared _InputOutputParser level
+        if not namespace.useGen3:
+            warnings.warn("The --gen2 flag is deprecated; it will be removed after release 23.",
+                          category=FutureWarning)
+        return namespace
+
 
 class _IngestOnlyParser(argparse.ArgumentParser):
     """An argument parser for data needed by dataset ingestion.
@@ -109,6 +118,14 @@ def __init__(self):
             parents=[_InputOutputParser(), _ProcessingParser()],
             add_help=True)
 
+    def parse_args(self, args=None, namespace=None):
+        namespace = super().parse_args(args, namespace)
+        # Code duplication; too hard to implement at shared _InputOutputParser level
+        if not namespace.useGen3:
+            warnings.warn("The --gen2 flag is deprecated; it will be removed after release 23.",
+                          category=FutureWarning)
+        return namespace
+
 
 class _FormattedType:
     """An argparse type converter that requires strings in a particular format.