Merge pull request #15614 from [BEAM-12953] [Playground] Create protobuf file for front-back communication

* Add protofile

* Fix typos.

* add proto/grpc as dependencies

* Change protobuf file

* Renamed some fields and inserted SDK_UNSPECIFIED status

* Refactoring proto file

* Change int32 pipeline_id to string pipeline_uuid

* Edit comments for some messages.

Co-authored-by: gravicapa <dasha.m91@gmail.com>
Co-authored-by: Ilya Kozyrev <ilya.kozyrev@akvelon.com>
Co-authored-by: Pavel Avilov <avilovpavel6@gmail.com>

Author: 4 people

playground/backend/go.mod

@@ -15,4 +15,9 @@
 
 module beam.apache.org/playground/backend
 
-go 1.16
+go 1.16
+
+require (
+	google.golang.org/grpc v1.41.0
+	google.golang.org/protobuf v1.27.1
+)

playground/playground/v1/playground.proto

@@ -0,0 +1,95 @@
+/*
+ * 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.
+ */
+
+syntax = "proto3";
+
+option go_package = "github.com/apache/beam/playground/v1;playground";
+package playground.v1;
+
+enum Sdk {
+  SDK_UNSPECIFIED = 0;
+  SDK_JAVA = 1;
+  SDK_GO = 2;
+  SDK_PYTHON = 3;
+  SDK_SCIO = 4;
+}
+
+enum Status {
+  STATUS_UNSPECIFIED = 0;
+  STATUS_EXECUTING = 1;
+  STATUS_FINISHED = 2;
+  STATUS_ERROR = 3;
+}
+
+// RunCodeRequest represents a code text and options of SDK which executes the code.
+message RunCodeRequest {
+  string code = 1;
+  Sdk sdk = 2;
+}
+
+// RunCodeResponse contains information of the pipeline uuid.
+message RunCodeResponse {
+  string pipeline_uuid = 1;
+}
+
+// CheckStatusRequest contains information of the pipeline uuid.
+message CheckStatusRequest {
+  string pipeline_uuid = 1;
+}
+
+// StatusInfo contains information about the status of the code execution.
+message CheckStatusResponse {
+  Status status = 1;
+}
+
+// GetCompileOutputRequest contains information of the pipeline uuid.
+message GetCompileOutputRequest {
+  string pipeline_uuid = 1;
+}
+
+// GetCompileOutputResponse represents the result of the compiled code.
+message GetCompileOutputResponse {
+  string output = 1;
+  Status compilation_status = 2;
+}
+
+// GetRunOutputRequest contains information of the pipeline uuid.
+message GetRunOutputRequest {
+  string pipeline_uuid = 1;
+}
+
+// RunOutputResponse represents the result of the executed code.
+message GetRunOutputResponse {
+  string output = 1;
+  Status compilation_status = 2;
+}
+
+service PlaygroundService {
+
+  // Submit the job for an execution and get the pipeline uuid.
+  rpc RunCode(RunCodeRequest) returns (RunCodeResponse);
+
+  // Get the status of pipeline execution.
+  rpc CheckStatus(CheckStatusRequest) returns (CheckStatusResponse);
+
+  // Get the result of pipeline execution.
+  rpc GetRunOutput(GetRunOutputRequest) returns (GetRunOutputResponse);
+
+  // Get the result of pipeline compilation.
+  rpc GetCompileOutput(GetCompileOutputRequest) returns (GetCompileOutputResponse);
+}