status_builder.cc

// Copyright 2019 The MediaPipe Authors.
//
// Licensed 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.

#include "status_builder.h"

#include <memory>
#include <sstream>

#include "absl/memory/memory.h"
#include "absl/status/status.h"
#include "absl/strings/str_cat.h"

namespace mediapipe {

StatusBuilder::StatusBuilder(const StatusBuilder &sb)
    : impl_(sb.impl_ ? std::make_unique<Impl>(*sb.impl_) : nullptr) {}

StatusBuilder &StatusBuilder::operator=(const StatusBuilder &sb) {
  if (!sb.impl_) {
    impl_ = nullptr;
    return *this;
  }
  if (impl_) {
    *impl_ = *sb.impl_;
    return *this;
  }
  impl_ = std::make_unique<Impl>(*sb.impl_);

  return *this;
}

StatusBuilder &StatusBuilder::SetAppend() & {
  if (!impl_)
    return *this;
  impl_->join_style = Impl::MessageJoinStyle::kAppend;
  return *this;
}

StatusBuilder &&StatusBuilder::SetAppend() && { return std::move(SetAppend()); }

StatusBuilder &StatusBuilder::SetPrepend() & {
  if (!impl_)
    return *this;
  impl_->join_style = Impl::MessageJoinStyle::kPrepend;
  return *this;
}

StatusBuilder &&StatusBuilder::SetPrepend() && {
  return std::move(SetPrepend());
}

StatusBuilder &StatusBuilder::SetNoLogging() & {
  if (!impl_)
    return *this;
  impl_->no_logging = true;
  return *this;
}

StatusBuilder &&StatusBuilder::SetNoLogging() && {
  return std::move(SetNoLogging());
}

StatusBuilder::operator absl::Status() const & {
  return StatusBuilder(*this).JoinMessageToStatus();
}

StatusBuilder::operator absl::Status() && { return JoinMessageToStatus(); }

absl::Status StatusBuilder::JoinMessageToStatus() {
  if (!impl_) {
    return absl::OkStatus();
  }
  return impl_->JoinMessageToStatus();
}

absl::Status StatusBuilder::Impl::JoinMessageToStatus() {
  if (stream.str().empty() || no_logging) {
    return status;
  }
  return absl::Status(status.code(), [this]() {
    switch (join_style) {
    case MessageJoinStyle::kAnnotate:
      return absl::StrCat(status.message(), "; ", stream.str());
    case MessageJoinStyle::kPrepend:
      return absl::StrCat(stream.str(), status.message());
    case MessageJoinStyle::kAppend:
      // fall through
    default:
      return absl::StrCat(status.message(), stream.str());
    }
  }());
}

StatusBuilder::Impl::Impl(const absl::Status &status,
                          mediapipe::source_location location)
    : status(status), location(location), stream() {}

StatusBuilder::Impl::Impl(absl::Status &&status,
                          mediapipe::source_location location)
    : status(std::move(status)), location(location), stream() {}

StatusBuilder::Impl::Impl(const Impl &other)
    : status(other.status), location(other.location),
      no_logging(other.no_logging), stream(other.stream.str()),
      join_style(other.join_style) {}

StatusBuilder::Impl &StatusBuilder::Impl::operator=(const Impl &other) {
  status = other.status;
  location = other.location;
  no_logging = other.no_logging;
  stream = std::ostringstream(other.stream.str());
  join_style = other.join_style;

  return *this;
}

} // namespace mediapipe