feat(storage): implement compose method (#912)

Author: leondialpad

storage/gcloud/aio/storage/storage.py

@@ -484,6 +484,43 @@ async def upload_from_filename(
             contents = await file_object.read()
             return await self.upload(bucket, object_name, contents, **kwargs)
 
+    # https://cloud.google.com/storage/docs/json_api/v1/objects/compose
+    async def compose(
+        self, bucket: str, object_name: str,
+        source_object_names: List[str], *,
+        content_type: Optional[str] = None,
+        params: Optional[Dict[str, str]] = None,
+        headers: Optional[Dict[str, Any]] = None,
+        session: Optional[Session] = None,
+        timeout: int = DEFAULT_TIMEOUT,
+    ) -> Dict[str, Any]:
+        url = (
+            f'{self._api_root_read}/{bucket}/o/'
+            f'{quote(object_name, safe="")}/compose'
+        )
+        headers = headers or {}
+        headers.update(await self._headers())
+        params = params or {}
+
+        payload: Dict[str, Any] = {
+            'sourceObjects': [{'name': name} for name in source_object_names],
+        }
+        if content_type:
+            payload['destination'] = {'contentType': content_type}
+        body = json.dumps(payload).encode('utf-8')
+        headers.update({
+            'Content-Length': str(len(body)),
+            'Content-Type': 'application/json; charset=UTF-8',
+        })
+
+        s = AioSession(session) if session else self.session
+        resp = await s.post(
+            url, headers=headers, params=params, timeout=timeout,
+            data=body,
+        )
+        data: Dict[str, Any] = await resp.json(content_type=None)
+        return data
+
     @staticmethod
     def _get_stream_len(stream: IO[AnyStr]) -> int:
         current = stream.tell()

storage/pyproject.rest.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "gcloud-rest-storage"
-version = "9.4.0"
+version = "9.5.0"
 description = "Python Client for Google Cloud Storage"
 readme = "README.rst"
 

storage/pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "gcloud-aio-storage"
-version = "9.4.0"
+version = "9.5.0"
 description = "Python Client for Google Cloud Storage"
 readme = "README.rst"
 

storage/tests/integration/compose_test.py

@@ -0,0 +1,55 @@
+import uuid
+
+import pytest
+from gcloud.aio.auth import BUILD_GCLOUD_REST  # pylint: disable=no-name-in-module
+from gcloud.aio.storage import Storage
+
+# Selectively load libraries based on the package
+if BUILD_GCLOUD_REST:
+    from requests import Session
+else:
+    from aiohttp import ClientSession as Session
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize(
+    'shard_data,expected_data,content_type,file_extension', [
+        (['foo ', 'bar'], b'foo bar', 'text/plain', 'txt'),
+        (['{"foo":', '1,', '"bar":2}'],
+         b'{"foo":1,"bar":2}', 'application/json', 'json'),
+    ],
+)
+async def test_compose(
+    bucket_name, creds, shard_data,
+    expected_data, content_type, file_extension,
+):
+    def random_name():
+        return f'{uuid.uuid4().hex}/{uuid.uuid4().hex}.{file_extension}'
+
+    shard_names = [random_name() for _ in shard_data]
+    object_name = random_name()
+
+    async with Session() as session:
+        storage = Storage(service_file=creds, session=session)
+
+        for shard_name, shard_datum in zip(shard_names, shard_data):
+            await storage.upload(
+                bucket_name,
+                shard_name,
+                shard_datum,
+                metadata={
+                    'Content-Disposition': 'inline',
+                },
+            )
+        res = await storage.compose(
+            bucket_name,
+            object_name,
+            shard_names,
+            content_type=content_type,
+        )
+
+        assert res['name'] == object_name
+        assert res['contentType'] == content_type
+
+        downloaded_data = await storage.download(bucket_name, res['name'])
+        assert downloaded_data == expected_data