[io] Switch to entrypoints when specyfying writers

libs/garf_io/garf_io/__init__.py

@@ -12,4 +12,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-__version__ = '0.0.2'
+__version__ = '0.0.3'

libs/garf_io/garf_io/exceptions.py

@@ -0,0 +1,19 @@
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Defines common library exceptions."""
+
+
+class GarfIoError(Exception):
+  """Base class for all library exceptions."""

libs/garf_io/garf_io/writer.py

@@ -15,11 +15,17 @@
 
 from __future__ import annotations
 
-from importlib import import_module
+import inspect
+from importlib.metadata import entry_points
 
+from garf_io import exceptions
 from garf_io.writers import abs_writer
 
 
+class GarfIoWriterError(exceptions.GarfIoError):
+  """Writer specific exception."""
+
+
 def create_writer(
   writer_option: str, **kwargs: str
 ) -> type[abs_writer.AbsWriter]:
@@ -35,22 +41,16 @@ def create_writer(
   Returns:
       Concrete instantiated writer.
   """
-  if writer_option in ('bq', 'bigquery'):
-    writer_module = import_module('garf_io.writers.bigquery_writer')
-    return writer_module.BigQueryWriter(**kwargs)
-  if writer_option == 'sqldb':
-    writer_module = import_module('garf_io.writers.sqldb_writer')
-    return writer_module.SqlAlchemyWriter(**kwargs)
-  if writer_option in ('sheet', 'sheets'):
-    writer_module = import_module('garf_io.writers.sheets_writer')
-    return writer_module.SheetWriter(**kwargs)
-  if writer_option == 'console':
-    writer_module = import_module('garf_io.writers.console_writer')
-    return writer_module.ConsoleWriter(**kwargs)
-  if writer_option == 'csv':
-    writer_module = import_module('garf_io.writers.csv_writer')
-    return writer_module.CsvWriter(**kwargs)
-  if writer_option == 'json':
-    writer_module = import_module('garf_io.writers.json_writer')
-    return writer_module.JsonWriter(**kwargs)
-  return import_module('garf_io.writers.null_writer').NullWriter(writer_option)
+  writers = entry_points(group='garf_writer')
+  found_writers = {}
+  for writer in writers:
+    try:
+      writer_module = writer.load()
+      for name, obj in inspect.getmembers(writer_module):
+        if inspect.isclass(obj) and issubclass(obj, abs_writer.AbsWriter):
+          found_writers[writer.name] = getattr(writer_module, name)
+    except ModuleNotFoundError:
+      continue
+  if concrete_writer := found_writers.get(writer_option):
+    return concrete_writer(**kwargs)
+  raise GarfIoWriterError(f'{writer_option} is unknown writer type!')

libs/garf_io/pyproject.toml

@@ -57,3 +57,12 @@ sheets = [
 all = [
   "garf-io[bq,sheets,sqlalchemy]"
 ]
+[project.entry-points.garf_writer]
+bq = "garf_io.writers.bigquery_writer"
+bigquery = "garf_io.writers.bigquery_writer"
+console = "garf_io.writers.console_writer"
+csv = "garf_io.writers.csv_writer"
+json = "garf_io.writers.json_writer"
+sheet = "garf_io.writers.sheets_writer"
+sheets = "garf_io.writers.sheets_writer"
+sqldb = "garf_io.writers.sqldb_writer"

libs/garf_io/tests/unit/test_writer.py

@@ -56,5 +56,5 @@ def test_create_writer_returns_correct_fields_for_json_option():
 
 
 def test_null_writer_raises_unknown_writer_error():
-  with pytest.raises(ValueError):
+  with pytest.raises(writer.GarfIoWriterError):
     writer.create_writer('non-existing-option')