Status KnowledgeBankGrpcServiceImpl::StartSessionIfNecessary()

in research/carls/knowledge_bank_grpc_service.cc [353:409]
56 lines of code
17 McCabe index (conditional complexity)

Status KnowledgeBankGrpcServiceImpl::StartSessionIfNecessary(
    const std::string& session_handle, const bool require_candidate_sampler,
    const bool require_memory_store) {
  StartSessionRequest request;
  request.ParseFromString(session_handle);
  if (require_candidate_sampler &&
      !request.config().has_candidate_sampler_config()) {
    return Status(StatusCode::FAILED_PRECONDITION,
                  "candidate_sampler_config is required but is empty.");
  }
  if (require_memory_store && !request.config().has_memory_store_config()) {
    return Status(StatusCode::FAILED_PRECONDITION,
                  "memory_store_config is required but is empty.");
  }
  absl::MutexLock lock(&map_mu_);
  if (request.config().has_knowledge_bank_config() &&
      !kb_map_.contains(session_handle)) {
    // Creates a new KnowledgeBank.
    auto knowledge_bank =
        KnowledgeBankFactory::Make(request.config().knowledge_bank_config(),
                                   request.config().embedding_dimension());
    if (knowledge_bank == nullptr) {
      return Status(StatusCode::INTERNAL, "Creating KnowledgeBank failed.");
    }
    kb_map_[session_handle] = std::move(knowledge_bank);
  }
  if (request.config().has_gradient_descent_config() &&
      !gd_map_.contains(session_handle)) {
    auto optimizer = GradientDescentOptimizer::Create(
        request.config().embedding_dimension(),
        request.config().gradient_descent_config());
    if (optimizer == nullptr) {
      return Status(StatusCode::INTERNAL,
                    "Creating GradientDescentOptimizer failed.");
    }
    gd_map_[session_handle] = std::move(optimizer);
  }
  if (request.config().has_candidate_sampler_config() &&
      !cs_map_.contains(session_handle)) {
    auto sampler = candidate_sampling::SamplerFactory::Make(
        request.config().candidate_sampler_config());
    if (sampler == nullptr) {
      return Status(StatusCode::INTERNAL, "Creating CandidateSampler failed.");
    }
    cs_map_[session_handle] = std::move(sampler);
  }
  if (request.config().has_memory_store_config() &&
      !ms_map_.contains(session_handle)) {
    auto memory_store = memory_store::MemoryStoreFactory::Make(
        request.config().memory_store_config());
    if (memory_store == nullptr) {
      return Status(StatusCode::INTERNAL, "Creating MemoryStore failed.");
    }
    ms_map_[session_handle] = std::move(memory_store);
  }
  return Status::OK;
}