Revert "add PetrelBackend (#291)" (#293)

This reverts commit 7f80a2c6.

mmcv/fileio/file_client.py

 import inspect
-import warnings
 from abc import ABCMeta, abstractmethod
 
 
@@ -21,63 +20,18 @@ class BaseStorageBackend(metaclass=ABCMeta):
 
 
 class CephBackend(BaseStorageBackend):
-    """Ceph storage backend.
+    """Ceph storage backend."""
 
-    Args:
-        path_mapping (dict|None): path mapping dict from local path to Petrel
-            path. When `path_mapping={'src': 'dst'}`, `src` in `filepath` will
-            be replaced by `dst`. Default: None.
-    """
-
-    def __init__(self, path_mapping=None):
+    def __init__(self):
         try:
             import ceph
-            warnings.warn('Ceph is deprecate in favor of Petrel.')
         except ImportError:
             raise ImportError('Please install ceph to enable CephBackend.')
 
         self._client = ceph.S3Client()
-        assert isinstance(path_mapping, dict) or path_mapping is None
-        self.path_mapping = path_mapping
-
-    def get(self, filepath):
-        filepath = str(filepath)
-        if self.path_mapping is not None:
-            for k, v in self.path_mapping.items():
-                filepath = filepath.replace(k, v)
-        value = self._client.Get(filepath)
-        value_buf = memoryview(value)
-        return value_buf
-
-    def get_text(self, filepath):
-        raise NotImplementedError
-
-
-class PetrelBackend(BaseStorageBackend):
-    """Petrel storage backend (for internal use).
-
-    Args:
-        path_mapping (dict|None): path mapping dict from local path to Petrel
-            path. When `path_mapping={'src': 'dst'}`, `src` in `filepath` will
-            be replaced by `dst`. Default: None.
-    """
-
-    def __init__(self, path_mapping=None):
-        try:
-            import petrel_client
-        except ImportError:
-            raise ImportError('Please install petrel_client to enable '
-                              'PetrelBackend.')
-
-        self._client = petrel_client.client.Client()
-        assert isinstance(path_mapping, dict) or path_mapping is None
-        self.path_mapping = path_mapping
 
     def get(self, filepath):
         filepath = str(filepath)
-        if self.path_mapping is not None:
-            for k, v in self.path_mapping.items():
-                filepath = filepath.replace(k, v)
         value = self._client.Get(filepath)
         value_buf = memoryview(value)
         return value_buf
@@ -210,7 +164,6 @@ class FileClient(object):
         'ceph': CephBackend,
         'memcached': MemcachedBackend,
         'lmdb': LmdbBackend,
-        'petrel': PetrelBackend,
     }
 
     def __init__(self, backend='disk', **kwargs):

tests/test_fileclient.py

@@ -8,7 +8,6 @@ import mmcv
 from mmcv import BaseStorageBackend, FileClient
 
 sys.modules['ceph'] = MagicMock()
-sys.modules['petrel_client'] = MagicMock()
 sys.modules['mc'] = MagicMock()
 
 
@@ -62,9 +61,6 @@ class TestFileClient(object):
 
     @patch('ceph.S3Client', MockS3Client)
     def test_ceph_backend(self):
-        with pytest.warns(
-                Warning, match='Ceph is deprecate in favor of Petrel.'):
-            FileClient('ceph')
         ceph_backend = FileClient('ceph')
 
         # input path is Path object
@@ -83,56 +79,6 @@ class TestFileClient(object):
         img = mmcv.imfrombytes(img_bytes)
         assert img.shape == self.img_shape
 
-        # `path_mapping` is either None or dict
-        with pytest.raises(AssertionError):
-            FileClient('ceph', path_mapping=1)
-        # test `path_mapping`
-        ceph_path = 's3://user/data'
-        ceph_backend = FileClient(
-            'ceph', path_mapping={str(self.test_data_dir): ceph_path})
-        ceph_backend.client._client.Get = MagicMock(
-            return_value=ceph_backend.client._client.Get(self.img_path))
-        img_bytes = ceph_backend.get(self.img_path)
-        img = mmcv.imfrombytes(img_bytes)
-        assert img.shape == self.img_shape
-        ceph_backend.client._client.Get.assert_called_with(
-            str(self.img_path).replace(str(self.test_data_dir), ceph_path))
-
-    @patch('petrel_client.client.Client', MockS3Client)
-    def test_petrel_backend(self):
-        petrel_backend = FileClient('petrel')
-
-        # input path is Path object
-        with pytest.raises(NotImplementedError):
-            petrel_backend.get_text(self.text_path)
-        # input path is str
-        with pytest.raises(NotImplementedError):
-            petrel_backend.get_text(str(self.text_path))
-
-        # input path is Path object
-        img_bytes = petrel_backend.get(self.img_path)
-        img = mmcv.imfrombytes(img_bytes)
-        assert img.shape == self.img_shape
-        # input path is str
-        img_bytes = petrel_backend.get(str(self.img_path))
-        img = mmcv.imfrombytes(img_bytes)
-        assert img.shape == self.img_shape
-
-        # `path_mapping` is either None or dict
-        with pytest.raises(AssertionError):
-            FileClient('petrel', path_mapping=1)
-        # test `path_mapping`
-        petrel_path = 's3://user/data'
-        petrel_backend = FileClient(
-            'petrel', path_mapping={str(self.test_data_dir): petrel_path})
-        petrel_backend.client._client.Get = MagicMock(
-            return_value=petrel_backend.client._client.Get(self.img_path))
-        img_bytes = petrel_backend.get(self.img_path)
-        img = mmcv.imfrombytes(img_bytes)
-        assert img.shape == self.img_shape
-        petrel_backend.client._client.Get.assert_called_with(
-            str(self.img_path).replace(str(self.test_data_dir), petrel_path))
-
     @patch('mc.MemcachedClient.GetInstance', MockMemcachedClient)
     @patch('mc.pyvector', MagicMock)
     @patch('mc.ConvertBuffer', lambda x: x.content)