grpc/examples/pubsub/subscriber.cc

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#include <grpc++/client_context.h>

#include "examples/pubsub/subscriber.h"

using tech::pubsub::Topic;
using tech::pubsub::DeleteTopicRequest;
using tech::pubsub::GetTopicRequest;
using tech::pubsub::SubscriberService;
using tech::pubsub::ListTopicsRequest;
using tech::pubsub::ListTopicsResponse;
using tech::pubsub::PublishRequest;
using tech::pubsub::PubsubMessage;

namespace grpc {
namespace examples {
namespace pubsub {

Subscriber::Subscriber(std::shared_ptr<Channel> channel)
    : stub_(SubscriberService::NewStub(channel)) {}

void Subscriber::Shutdown() { stub_.reset(); }

Status Subscriber::CreateSubscription(const grpc::string& topic,
                                      const grpc::string& name) {
  tech::pubsub::Subscription request;
  tech::pubsub::Subscription response;
  ClientContext context;

  request.set_topic(topic);
  request.set_name(name);

  return stub_->CreateSubscription(&context, request, &response);
}

Status Subscriber::GetSubscription(const grpc::string& name,
                                   grpc::string* topic) {
  tech::pubsub::GetSubscriptionRequest request;
  tech::pubsub::Subscription response;
  ClientContext context;

  request.set_subscription(name);

  Status s = stub_->GetSubscription(&context, request, &response);
  *topic = response.topic();
  return s;
}

Status Subscriber::DeleteSubscription(const grpc::string& name) {
  tech::pubsub::DeleteSubscriptionRequest request;
  proto2::Empty response;
  ClientContext context;

  request.set_subscription(name);

  return stub_->DeleteSubscription(&context, request, &response);
}

Status Subscriber::Pull(const grpc::string& name, grpc::string* data) {
  tech::pubsub::PullRequest request;
  tech::pubsub::PullResponse response;
  ClientContext context;

  request.set_subscription(name);
  Status s = stub_->Pull(&context, request, &response);
  if (s.IsOk()) {
    tech::pubsub::PubsubEvent event = response.pubsub_event();
    if (event.has_message()) {
      *data = event.message().data();
    }
    tech::pubsub::AcknowledgeRequest ack;
    proto2::Empty empty;
    ClientContext ack_context;
    ack.set_subscription(name);
    ack.add_ack_id(response.ack_id());
    stub_->Acknowledge(&ack_context, ack, &empty);
  }
  return s;
}

}  // namespace pubsub
}  // namespace examples
}  // namespace grpc