fix: allow passing just key to ImportCommandHandler

so config can override designated handler, and command still work

src/wuttasync/cli/base.py

@@ -50,19 +50,35 @@ class ImportCommandHandler(GenericHandler):
     create this handler and call its :meth:`run()` method.
 
     This handler does not know how to import/export data, but it knows
-    how to make its :attr:`import_handler` do it.
+    how to make its :attr:`import_handler` do it.  Likewise, the
+    import handler is not "CLI-aware" - so this provides the glue.
 
     :param import_handler: During construction, caller can specify the
        :attr:`import_handler` as any of:
 
        * import handler instance
        * import handler factory (e.g. class)
-       * import handler spec (cf. :func:`~wuttjamaican:wuttjamaican.util.load_object()`)
+       * import handler :term:`spec`
 
-       For example::
+    :param key: Optional :term:`import/export key` to use for handler
+       lookup.  Only used if ``import_handler`` param is not set.
 
-          handler = ImportCommandHandler(
-              config, import_handler='wuttasync.importing.csv:FromCsvToWutta')
+    Typical usage for custom commands will be to provide the spec::
+
+       handler = ImportCommandHandler(
+           config, "poser.importing.foo:FromFooToPoser"
+       )
+
+    Library authors may prefer to use the import/export key; this lets
+    the command work with any designated handler::
+
+       handler = ImportCommandHandler(
+           config, key="import.to_poser.from_foo"
+       )
+
+    See also
+    :meth:`~wuttasync.app.WuttaSyncAppProvider.get_import_handler()`
+    which does the lookup by key.
     """
 
     import_handler = None
@@ -71,7 +87,7 @@ class ImportCommandHandler(GenericHandler):
     invoked when command runs.  See also :meth:`run()`.
     """
 
-    def __init__(self, config, import_handler=None):
+    def __init__(self, config, import_handler=None, key=None):
         super().__init__(config)
 
         if import_handler:
@@ -83,6 +99,9 @@ class ImportCommandHandler(GenericHandler):
                 factory = self.app.load_object(import_handler)
                 self.import_handler = factory(self.config)
 
+        elif key:
+            self.import_handler = self.app.get_import_handler(key, require=True)
+
     def run(self, params, progress=None):  # pylint: disable=unused-argument
         """
         Run the import/export job(s) based on command line params.

src/wuttasync/cli/import_csv.py

@@ -38,7 +38,5 @@ def import_csv(ctx: typer.Context, **kwargs):  # pylint: disable=unused-argument
     Import data from CSV file(s) to Wutta DB
     """
     config = ctx.parent.wutta_config
-    handler = ImportCommandHandler(
-        config, import_handler="wuttasync.importing.csv:FromCsvToWutta"
-    )
+    handler = ImportCommandHandler(config, key="import.to_wutta.from_csv")
     handler.run(ctx.params)

src/wuttasync/cli/import_versions.py

@@ -69,7 +69,5 @@ def import_versions(  # pylint: disable=unused-argument
         )
         sys.exit(1)
 
-    handler = ImportCommandHandler(
-        config, import_handler="wuttasync.importing.versions:FromWuttaToVersions"
-    )
+    handler = ImportCommandHandler(config, key="import.to_versions.from_wutta")
     handler.run(ctx.params)

tests/cli/test_base.py

@@ -34,6 +34,10 @@ class TestImportCommandHandler(DataTestCase):
         handler = self.make_handler(import_handler=myhandler)
         self.assertIs(handler.import_handler, myhandler)
 
+        # as key
+        handler = self.make_handler(key="import.to_wutta.from_csv")
+        self.assertIsInstance(handler.import_handler, FromCsvToWutta)
+
     def test_run(self):
         handler = self.make_handler(
             import_handler="wuttasync.importing.csv:FromCsvToWutta"