Make mirror_file fail if file object already exists (#7134)

src/azul/indexer/mirror_controller.py

@@ -152,8 +152,13 @@ def mirror_file(self,
         deployment_is_stable = (config.deployment.is_stable
                                 and not config.deployment.is_unit_test
                                 and catalog not in config.integration_test_catalogs)
+
         if file_is_large and not deployment_is_stable:
             log.info('Not mirroring file to save cost: %r', file)
+        elif self.service.info_exists(catalog, file):
+            log.info('File is already mirrored, skipping upload: %r', file)
+        elif self.service.file_exists(catalog, file):
+            assert False, R('File object is already present', file)
         else:
             # Ensure we test with multiple parts on lower deployments
             part_size = FilePart.default_size if deployment_is_stable else FilePart.min_size

src/azul/indexer/mirror_service.py

@@ -191,9 +191,17 @@ def mirror_object_key(self, file: File) -> str:
     def info_object_key(self, file: File) -> str:
         return self._file_key('info', file, extension='.json')
 
-    def is_mirrored(self, catalog: CatalogName, file: File) -> bool:
+    def info_exists(self, catalog: CatalogName, file: File) -> bool:
         return self._get_info(catalog, file) is not None
 
+    def file_exists(self, catalog: CatalogName, file: File) -> bool:
+        try:
+            self._storage(catalog).head(self.mirror_object_key(file))
+        except StorageObjectNotFound:
+            return False
+        else:
+            return True
+
     def _file_key(self, prefix: str, file: File, *, extension: str = '') -> str:
         digest = file.digest
         assert all(c in string.hexdigits for c in digest.value), R(
@@ -214,17 +222,15 @@ def mirror_file(self, catalog: CatalogName, file: File):
         Upload the file in a single request. For larger files, use
         :meth:`begin_mirroring_file` instead.
         """
-        if self.is_mirrored(catalog, file):
-            log.info('File is already mirrored, skipping upload: %r', file)
-        else:
-            file_content = self._download(catalog, file)
-            self._storage(catalog).put(object_key=self.mirror_object_key(file),
-                                       data=file_content,
-                                       content_type=file.content_type)
-            hasher = get_resumable_hasher(file.digest.type)
-            hasher.update(file_content)
-            self._verify_digest(file, hasher)
-            self._put_info(catalog, file)
+        file_content = self._download(catalog, file)
+        self._storage(catalog).put(object_key=self.mirror_object_key(file),
+                                   data=file_content,
+                                   content_type=file.content_type,
+                                   overwrite=False)
+        hasher = get_resumable_hasher(file.digest.type)
+        hasher.update(file_content)
+        self._verify_digest(file, hasher)
+        self._put_info(catalog, file)
 
     def begin_mirroring_file(self, catalog: CatalogName, file: File) -> str:
         """
@@ -268,7 +274,9 @@ def finish_mirroring_file(self,
         Complete a multipart upload begun with :meth:`begin_mirroring_file`.
         """
         upload = self._get_upload(catalog, file, upload_id)
-        self._storage(catalog).complete_multipart_upload(upload, etags)
+        self._storage(catalog).complete_multipart_upload(upload,
+                                                         etags,
+                                                         overwrite=False)
         self._verify_digest(file, hasher)
         self._get_info(catalog, file)
         self._put_info(catalog, file)

src/azul/service/repository_controller.py

@@ -266,7 +266,7 @@ def download_file(self,
         plugin = self.repository_plugin(catalog)
 
         is_mirrored = (config.enable_mirroring
-                       and self.mirror_service.is_mirrored(catalog, file))
+                       and self.mirror_service.info_exists(catalog, file))
         if is_mirrored:
             download = MirrorFileDownload(
                 file=file,

src/azul/service/storage_service.py

@@ -29,6 +29,8 @@
     urlencode,
 )
 
+import botocore
+import botocore.exceptions
 from botocore.response import (
     StreamingBody,
 )
@@ -75,6 +77,10 @@ class StorageObjectNotFound(Exception):
     pass
 
 
+class StorageObjectExists(Exception):
+    pass
+
+
 class StorageService:
 
     def __init__(self, bucket_name: str | None = None):
@@ -92,7 +98,7 @@ def head(self, object_key: str) -> HeadObjectOutputTypeDef:
                                         Key=object_key)
         except self._s3.exceptions.ClientError as e:
             if int(e.response['Error']['Code']) == 404:
-                raise StorageObjectNotFound
+                raise StorageObjectNotFound(object_key)
             else:
                 raise e
 
@@ -101,7 +107,7 @@ def get(self, object_key: str) -> bytes:
             response = self._s3.get_object(Bucket=self.bucket_name,
                                            Key=object_key)
         except self._s3.exceptions.NoSuchKey:
-            raise StorageObjectNotFound
+            raise StorageObjectNotFound(object_key)
         else:
             return response['Body'].read()
 
@@ -110,12 +116,19 @@ def put(self,
             data: bytes,
             content_type: str | None = None,
             tagging: Tagging | None = None,
+            *,
+            overwrite: bool = True,
             **kwargs):
-        self._s3.put_object(Bucket=self.bucket_name,
-                            Key=object_key,
-                            Body=data,
-                            **self._object_creation_kwargs(content_type=content_type, tagging=tagging),
-                            **kwargs)
+        try:
+            self._s3.put_object(Bucket=self.bucket_name,
+                                Key=object_key,
+                                Body=data,
+                                **self._object_creation_kwargs(content_type=content_type,
+                                                               tagging=tagging,
+                                                               overwrite=overwrite),
+                                **kwargs)
+        except botocore.exceptions.ClientError as e:
+            self._handle_overwrite(e, object_key)
 
     def list(self, prefix: str) -> OrderedSet[str]:
         keys, num_keys = OrderedSet(), 0
@@ -155,15 +168,22 @@ def upload_multipart_part(self,
 
     def complete_multipart_upload(self,
                                   upload: MultipartUpload,
-                                  etags: Sequence[str]) -> None:
+                                  etags: Sequence[str],
+                                  *,
+                                  overwrite: bool = True,
+                                  ) -> None:
         parts = [
             {
                 'PartNumber': index + 1,
                 'ETag': etag
             }
             for index, etag in enumerate(etags)
         ]
-        upload.complete(MultipartUpload={'Parts': parts})
+        try:
+            upload.complete(MultipartUpload={'Parts': parts},
+                            **self._object_creation_kwargs(overwrite=overwrite))
+        except botocore.exceptions.ClientError as e:
+            self._handle_overwrite(e, upload.object_key)
 
     def upload(self,
                file_path: str,
@@ -179,14 +199,19 @@ def upload(self,
         if tagging:
             self.put_object_tagging(object_key, tagging)
 
-    def _object_creation_kwargs(self, *,
+    def _object_creation_kwargs(self,
+                                *,
                                 content_type: str | None = None,
-                                tagging: Tagging | None = None):
+                                tagging: Tagging | None = None,
+                                overwrite: bool = True
+                                ) -> Mapping[str, str]:
         kwargs = {}
         if content_type is not None:
             kwargs['ContentType'] = content_type
         if tagging is not None:
             kwargs['Tagging'] = urlencode(tagging)
+        if overwrite is False:
+            kwargs['IfNoneMatch'] = '*'
         return kwargs
 
     def get_presigned_url(self, key: str, file_name: str | None = None) -> str:
@@ -281,6 +306,17 @@ def _time_until_object_expires(self,
                       expiration_header, expected_expiry)
         return time_left
 
+    def _handle_overwrite(self,
+                          exception: botocore.exceptions.ClientError,
+                          object_key: str
+                          ):
+        error = exception.response['Error']
+        code, condition = error['Code'], error['Condition']
+        if code == 'PreconditionFailed' and condition == 'If-None-Match':
+            raise StorageObjectExists(object_key)
+        else:
+            raise exception
+
 
 @dataclass
 class Part:

test/indexer/test_mirror_controller.py

@@ -75,9 +75,18 @@ def test_mirroring(self):
                 with self.subTest('mirror_partition'):
                     file, file_message = self._test_mirror_partition(partition_message)
 
-                    with self.subTest('mirror_file'):
+                    with self.subTest('mirror_file', corrupted=False, exists=False):
                         self._test_mirror_file(file, file_message)
 
+                    self._s3.delete_object(Bucket=self.mirror_bucket,
+                                           Key=self.mirror_controller.service.info_object_key(file))
+
+                    with self.subTest('mirror_file', corrupted=True):
+                        self._test_corrupted_download(file_message)
+
+                    with self.subTest('mirror_file', corrupted=False, exists=True):
+                        self._test_reuploaded_file(file_message)
+
     _file_contents = b'lorem ipsum dolor sit\n'
 
     @property
@@ -136,14 +145,23 @@ def _test_mirror_file(self, file, file_message):
                                        Key=self.mirror_controller.service.mirror_object_key(file))
         mirrored_file_contents = response['Body'].read()
         self.assertEqual(mirrored_file_contents, self._file_contents)
+
+    def _test_corrupted_download(self, file_message):
+        event = [self._mock_sqs_record(file_message)]
         corrupted_contents = self._file_contents[:-1] + b'Q'
         with patch.object(MirrorService, '_download', return_value=corrupted_contents):
-            # Force reupload attempt in spite of info object being present
-            with patch.object(MirrorService, 'is_mirrored', return_value=False):
-                with self.assertRaises(AssertionError) as e:
-                    self.mirror_controller.mirror(event)
+            with self.assertRaises(AssertionError) as e:
+                self.mirror_controller.mirror(event)
             self.assertTrue(R.caused(e.exception))
 
+    def _test_reuploaded_file(self, file_message):
+        event = [self._mock_sqs_record(file_message)]
+        with patch.object(MirrorService, '_download', return_value=self._file_contents):
+            with self.assertRaises(AssertionError) as e:
+                self.mirror_controller.mirror(event)
+        self.assertTrue(R.caused(e.exception))
+        self.assertEqual(e.exception.args[0].args[0], 'File object is already present')
+
     def test_info_schema(self):
         client = http_client(log)
         file = MagicMock(content_type='text/plain')

test/service/test_repository_files.py

@@ -117,7 +117,7 @@ def assertUrlEqual(self, a: Union[str, furl], b: Union[str, furl]):
 @mock.patch.object(SourceService, '_put', new=MagicMock())
 @mock.patch.object(SourceService, '_get')
 @mock.patch.object(BaseMirrorService,
-                   'is_mirrored',
+                   'info_exists',
                    new=MagicMock(return_value=False))
 class TestRepositoryFilesWithTDR(DCP2TestCase, RepositoryFilesTestCase):
 
@@ -250,7 +250,7 @@ def _test(*, authenticate: bool, cache: bool):
 
 
 @mock.patch.object(BaseMirrorService,
-                   'is_mirrored',
+                   'info_exists',
                    new=MagicMock(return_value=False))
 class TestRepositoryFilesWithDSS(DCP1TestCase,
                                  RepositoryFilesTestCase,
@@ -424,7 +424,7 @@ def test_repository_files(self):
         mirror_service = MirrorService(schema_url_func=MagicMock())
         with mock.patch.object(MirrorService, '_download', return_value=file_content):
             mirror_service.mirror_file(self.catalog, file)
-        self.assertTrue(mirror_service.is_mirrored(self.catalog, file))
+        self.assertTrue(mirror_service.info_exists(self.catalog, file))
 
         client = http_client(log)
         args = dict(catalog=self.catalog, version=file_version)