Add sample for CRUD on GCS.

(or at least, CRD)

Author: Jerjou Cheng

storage/api/crud_object.py

@@ -0,0 +1,149 @@
+#!/usr/bin/env python
+
+# Copyright (C) 2016 Google Inc.
+#
+# 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
+#
+#            http://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.
+
+"""Application for uploading an object using the Cloud Storage API.
+
+This sample is used on this page:
+
+    https://cloud.google.com/storage/docs/json_api/v1/json-api-python-samples
+
+For more information, see the README.md under /storage.
+"""
+
+import argparse
+import filecmp
+import json
+import tempfile
+
+from googleapiclient import discovery
+from googleapiclient import http
+
+from oauth2client.client import GoogleCredentials
+
+
+def main(bucket, filename, readers=[], owners=[]):
+    print('Uploading object..')
+    resp = upload_object(bucket, filename, readers, owners)
+    print(json.dumps(resp, indent=2))
+
+    print('Fetching object..')
+    with tempfile.NamedTemporaryFile(mode='w+b') as tmpfile:
+        get_object(bucket, filename, out_file=tmpfile)
+        tmpfile.seek(0)
+
+        if not filecmp.cmp(filename, tmpfile.name):
+            raise Exception('Downloaded file != uploaded object')
+
+    print('Deleting object..')
+    resp = delete_object(bucket, filename)
+    if resp:
+        print(json.dumps(resp, indent=2))
+    print 'Done'
+
+
+def create_service():
+    # Get the application default credentials. When running locally, these are
+    # available after running `gcloud init`. When running on compute
+    # engine, these are available from the environment.
+    credentials = GoogleCredentials.get_application_default()
+
+    # Construct the service object for interacting with the Cloud Storage API -
+    # the 'storage' service, at version 'v1'.
+    # You can browse other available api services and versions here:
+    #     http://g.co/dev/api-client-library/python/apis/
+    return discovery.build('storage', 'v1', credentials=credentials)
+
+
+def upload_object(bucket, filename, readers, owners):
+    service = create_service()
+
+    # This is the request body as specified:
+    # http://g.co/cloud/storage/docs/json_api/v1/objects/insert#request
+    body = {
+        'name': filename,
+    }
+
+    # If specified, create the access control objects and add them to the
+    # request body
+    if readers or owners:
+        body['acl'] = []
+    for r in readers:
+        body['acl'].append({
+            'entity': 'user-%s' % r,
+            'role': 'READER',
+            'email': r
+        })
+    for o in owners:
+        body['acl'].append({
+            'entity': 'user-%s' % o,
+            'role': 'OWNER',
+            'email': o
+        })
+
+    # Now insert them into the specified bucket as a media insertion.
+    # http://g.co/dev/resources/api-libraries/documentation/storage/v1/python/latest/storage_v1.objects.html#insert
+    with open(filename, 'rb') as f:
+        req = service.objects().insert(
+            bucket=bucket, body=body,
+            # You can also just set media_body=filename, but # for the sake of
+            # demonstration, pass in the more generic file handle, which could
+            # very well be a StringIO or similar.
+            media_body=http.MediaIoBaseUpload(f, 'application/octet-stream'))
+        resp = req.execute()
+
+    return resp
+
+
+def get_object(bucket, filename, out_file):
+    service = create_service()
+
+    # Use get_media instead of get to get the actual contents of the object.
+    # http://g.co/dev/resources/api-libraries/documentation/storage/v1/python/latest/storage_v1.objects.html#get_media
+    req = service.objects().get_media(bucket=bucket, object=filename)
+
+    downloader = http.MediaIoBaseDownload(out_file, req)
+
+    done = False
+    while done is False:
+        status, done = downloader.next_chunk()
+        print("Download {}%.".format(int(status.progress() * 100)))
+
+    return out_file
+
+
+def delete_object(bucket, filename):
+    service = create_service()
+
+    req = service.objects().delete(bucket=bucket, object=filename)
+    resp = req.execute()
+
+    return resp
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(
+        description=__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter)
+    parser.add_argument('filename', help='The name of the file to upload')
+    parser.add_argument('bucket', help='Your Cloud Storage bucket.')
+    parser.add_argument('--reader', action='append', default=[],
+                        help='Your Cloud Storage bucket.')
+    parser.add_argument('--owner', action='append', default=[],
+                        help='Your Cloud Storage bucket.')
+
+    args = parser.parse_args()
+
+    main(args.bucket, args.filename, args.reader, args.owner)

storage/api/crud_object_test.py

@@ -0,0 +1,22 @@
+# Copyright 2016, Google, Inc.
+# 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
+#
+#    http://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.
+
+from crud_object import main
+
+
+def test_main(cloud_config, capsys):
+    main(cloud_config.storage_bucket, __file__)
+    out, err = capsys.readouterr()
+
+    assert not re.search(r'Downloaded file [!]=', out)
+    assert re.search(r'Uploading.*Fetching.*Deleting.*Done', out)