/*
 * 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.
 */

/*
 * Protocol Buffers describing endpoints containing a service.
 */

syntax = "proto3";

package org.apache.beam.model.pipeline.v1;

option go_package = "pipeline_v1";
option java_package = "org.apache.beam.model.pipeline.v1";
option java_outer_classname = "Endpoints";

// A description of how to connect to a Beam API endpoint.
message ApiServiceDescriptor {
  // (Required) The URL to connect to.
  string url = 1;

  // (Optional) The method for authentication. If unspecified, access to the
  // url is already being performed in a trusted context (e.g. localhost,
  // private network).
  AuthenticationSpec authentication = 2;
}

message AuthenticationSpec {
  // (Required) A URN that describes the accompanying payload.
  // For any URN that is not recognized (by whomever is inspecting
  // it) the parameter payload should be treated as opaque and
  // passed as-is.
  string urn = 1;

  // (Optional) The data specifying any parameters to the URN. If
  // the URN does not require any arguments, this may be omitted.
  bytes payload = 2;
}

// TODO: Add authentication specifications as needed.
//message StandardAuthenticationSpecs {
//  enum Enum {
//    OAUTH2_CLIENT_CREDENTIALS_GRANT = 0 [(org.apache.beam.model.pipeline.v1.beam_urn) = "beam:authentication:oauth2_client_credentials_grant:v1"];
//  }
//}
//
//message OAuth2ClientCredentialsGrantPayload {
//  // (Required) The URL to submit a "client_credentials" grant type request for
//  // an OAuth access token which will be used as a bearer token for requests.
//  string url = 1;
//}
