[HUDI-845] Added locking capability to allow multiple writers (#2374)

* [HUDI-845] Added locking capability to allow multiple writers
1. Added LockProvider API for pluggable lock methodologies
2. Added Resolution Strategy API to allow for pluggable conflict resolution
3. Added TableService client API to schedule table services
4. Added Transaction Manager for wrapping actions within transactions

hudi-integ-test/src/test/resources/unit-test-cow-dag-spark-datasource.yaml

@@ -0,0 +1,43 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you 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.
+dag_name: unit-test-cow-dag-spark-datasource
+dag_rounds: 1
+dag_intermittent_delay_mins: 1
+dag_content:
+  first_insert:
+    config:
+      record_size: 70000
+      num_partitions_insert: 1
+      repeat_count: 2
+      num_records_insert: 100
+    type: SparkInsertNode
+    deps: none
+  first_upsert:
+    config:
+      record_size: 70000
+      num_partitions_insert: 1
+      repeat_count: 1
+      num_records_insert: 100
+    type: SparkUpsertNode
+    deps: first_insert
+  second_upsert:
+    config:
+      record_size: 70000
+      num_partitions_insert: 1
+      repeat_count: 1
+      num_records_insert: 100
+    type: SparkUpsertNode
+    deps: first_upsert