functions: consolidate redundant GCS samples (#4305)

* functions: remove redundant GCS sample

* Fix typo: data -> event

* Add missing integration test

* Data -> event fix, take 2

* Lint-fix attempt

* Fix lint

* Address comments: data -> event

* Test-fix: restore missing requirements-test.txt

Author: Ace Nassri

functions/gcs/README.md

@@ -88,12 +88,25 @@ def hello_pubsub(event, context):
 # [START functions_helloworld_storage]
 def hello_gcs(event, context):
     """Background Cloud Function to be triggered by Cloud Storage.
+       This generic function logs relevant data when a file is changed.
+
     Args:
-         event (dict): The dictionary with data specific to this type of event.
-         context (google.cloud.functions.Context): The Cloud Functions
-         event metadata.
+        event (dict):  The dictionary with data specific to this type of event.
+                       The `data` field contains a description of the event in
+                       the Cloud Storage `object` format described here:
+                       https://cloud.google.com/storage/docs/json_api/v1/objects#resource
+        context (google.cloud.functions.Context): Metadata of triggering event.
+    Returns:
+        None; the output is written to Stackdriver Logging
     """
-    print("File: {}.".format(event['objectId']))
+
+    print('Event ID: {}'.format(context.event_id))
+    print('Event type: {}'.format(context.event_type))
+    print('Bucket: {}'.format(event['bucket']))
+    print('File: {}'.format(event['name']))
+    print('Metageneration: {}'.format(event['metageneration']))
+    print('Created: {}'.format(event['timeCreated']))
+    print('Updated: {}'.format(event['updated']))
 # [END functions_helloworld_storage]
 
 

functions/gcs/main.py

@@ -1,4 +1,4 @@
-functions-framework==2.0.0
-mock==4.0.2
-pytest==6.0.1
+functions-framework==2.0.0	
+mock==4.0.2	
+pytest==6.0.1	
 uuid==1.30

functions/gcs/main_test.py

@@ -13,15 +13,27 @@
 # limitations under the License.
 
 # [START functions_storage_unit_test]
+import mock
+
 import main
 
 
 def test_print(capsys):
     name = 'test'
-    data = {'objectId': name}
+    event = {
+        'bucket': 'some-bucket',
+        'name': name,
+        'metageneration': 'some-metageneration',
+        'timeCreated': '0',
+        'updated': '0'
+    }
+
+    context = mock.MagicMock()
+    context.event_id = 'some-id'
+    context.event_type = 'gcs-event'
 
     # Call tested function
-    main.hello_gcs(data, None)
+    main.hello_gcs(event, context)
     out, err = capsys.readouterr()
-    assert out == 'File: {}.\n'.format(name)
+    assert 'File: {}\n'.format(name) in out
 # [END functions_storage_unit_test]

functions/gcs/requirements-test.txt

@@ -0,0 +1,74 @@
+# Copyright 2020 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
+#
+#     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.
+
+# [START functions_storage_integration_test]
+import datetime
+import os
+import subprocess
+import uuid
+
+import requests
+from requests.packages.urllib3.util.retry import Retry
+
+
+def test_print_name():
+    filename = str(uuid.uuid4())
+    port = 8089  # Each running framework instance needs a unique port
+
+    example_timestamp = datetime.datetime.now().isoformat()
+    storage_message = {
+        'data': {
+            'name': filename,
+            'bucket': 'my_bucket',
+            'metageneration': '1',
+            'timeCreated': example_timestamp,
+            'updated': example_timestamp
+        }
+    }
+
+    process = subprocess.Popen(
+      [
+        'functions-framework',
+        '--target', 'hello_gcs',
+        '--signature-type', 'event',
+        '--port', str(port)
+      ],
+      cwd=os.path.dirname(__file__),
+      stdout=subprocess.PIPE
+    )
+
+    # Send HTTP request simulating Pub/Sub message
+    # (GCF translates Pub/Sub messages to HTTP requests internally)
+    url = f'http://localhost:{port}/'
+
+    retry_policy = Retry(total=6, backoff_factor=1)
+    retry_adapter = requests.adapters.HTTPAdapter(
+      max_retries=retry_policy)
+
+    session = requests.Session()
+    session.mount(url, retry_adapter)
+
+    response = session.post(url, json=storage_message)
+
+    assert response.status_code == 200
+
+    # Stop the functions framework process
+    process.kill()
+    process.wait()
+    out, err = process.communicate()
+
+    print(out, err, response.content)
+
+    assert f'File: {filename}' in str(out)
+# [END functions_storage_integration_test]

functions/gcs/requirements.txt

@@ -61,7 +61,7 @@ def test_hello_gcs(uploaded_file):
         'functions',
         'logs',
         'read',
-        'hello_gcs',
+        'hello_gcs_generic',
         '--start-time',
         start_time
     ], stdout=subprocess.PIPE)