Add sink multitask example. (#64)

Author: doru1004

examples/cloud_object_storage/cos_sink_multitask.py

@@ -0,0 +1,90 @@
+#
+# Copyright IBM Corporation 2021
+#
+# 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.
+#
+
+import ray
+import rayvens
+import sys
+import time
+
+# This example demonstrates how to send objects to the AWS S3 or
+# IBM Cloud Object Storage.
+
+# Parse command-line arguments
+if len(sys.argv) < 5:
+    print(f'usage: {sys.argv[0]} <bucket> <access_key_id> <secret_access_key>'
+          '<endpoint> [<region>]')
+    sys.exit(1)
+bucket = sys.argv[1]
+access_key_id = sys.argv[2]
+secret_access_key = sys.argv[3]
+endpoint = sys.argv[4]
+region = None
+if len(sys.argv) == 6:
+    region = sys.argv[5]
+
+# Initialize Ray and Rayvens
+ray.init()
+
+# TODO: make header setting work for Kafka transport. Currently the
+# Camel-K component for Kafka does not propagate message headers. This
+# will be fixed by Camel-K 1.8.0 release.
+# rayvens.init(transport="kafka")
+rayvens.init()
+
+# Create an object stream
+stream = rayvens.Stream('upload-file')
+
+# Configure the sink
+sink_config = dict(kind='cloud-object-storage-sink',
+                   bucket_name=bucket,
+                   access_key_id=access_key_id,
+                   secret_access_key=secret_access_key,
+                   endpoint=endpoint)
+
+if region is not None:
+    sink_config['region'] = region
+
+# Run the sink
+sink = stream.add_sink(sink_config)
+
+
+# Operator sub-task:
+@ray.remote
+def sub_task(context, intermediate_data):
+    contents = "sub-task " + intermediate_data
+    print(contents)
+    sub_task_outgoing_event = rayvens.OutputEvent(
+        contents,
+        {"CamelAwsS3Key": "custom_file_" + intermediate_data + ".json"})
+    context.publish(sub_task_outgoing_event)
+
+
+# Operator task:
+@ray.remote
+def multi_part_task(context, incoming_event):
+    print("multi-part-task:", incoming_event)
+    for i in range(3):
+        sub_task.remote(context, str(i))
+
+
+# Add multi-task operator to stream.
+stream.add_multitask_operator(multi_part_task)
+
+# Send file contents to Cloud Object Storage:
+stream << "Random Event"
+
+# Run for a while
+time.sleep(10)