Add '--show inputs' option to 'pipetask build'.

Author: TallJimbo

doc/changes/DM-52738.feature.md

@@ -0,0 +1 @@
+Adds the `--show inputs` option to `pipetask build`.

python/lsst/ctrl/mpexec/cli/opt/options.py

@@ -322,7 +322,8 @@
         show subset labels and associated tasks; ``uri`` to show
         predicted dataset URIs of quanta; ``pipeline-graph`` for a
         text-based visualization of the pipeline (tasks and dataset types);
-        ``task-graph`` for a text-based visualization of just the tasks.
+        ``task-graph`` for a text-based visualization of just the tasks;
+        ``inputs`` for a list of overall-input dataset types.
         With -b, pipeline-graph and task-graph include additional information.
         """
     ),

python/lsst/ctrl/mpexec/showInfo.py

@@ -113,6 +113,7 @@ class ShowInfo:
         "pipeline-graph",
         "task-graph",
         "subsets",
+        "inputs",
     }
     graph_commands = {"graph", "workflow", "uri"}
 
@@ -186,6 +187,14 @@ def show_pipeline_info(self, pipeline_graph_factory: PipelineGraphFactory) -> No
                     visualization.show(
                         pipeline_graph_factory(visualization_only=True), self.stream, dataset_types=False
                     )
+                case "inputs":
+                    pg = pipeline_graph_factory(visualization_only=True)
+                    for dataset_type_name, dataset_type_node in sorted(pg.iter_overall_inputs()):
+                        print(
+                            dataset_type_name,
+                            dataset_type_node.dimensions,
+                            dataset_type_node.storage_class_name,
+                        )
                 case _:
                     raise RuntimeError(f"Unexpectedly tried to process command {command!r}.")
             self.handled.add(command)