3rdparty/libprocess/src/logging.cpp

// 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 <string>

#include "process/delay.hpp"
#include "process/future.hpp"
#include "process/help.hpp"
#include "process/http.hpp"
#include "process/logging.hpp"

#include "stout/numify.hpp"
#include "stout/option.hpp"
#include "stout/stringify.hpp"
#include "stout/try.hpp"

namespace process {

Future<http::Response> Logging::toggle(const http::Request& request)
{
  Option<std::string> level = request.url.query.get("level");
  Option<std::string> duration = request.url.query.get("duration");

  if (level.isNone() && duration.isNone()) {
    return http::OK(stringify(FLAGS_v) + "\n");
  }

  if (level.isSome() && duration.isNone()) {
    return http::BadRequest("Expecting 'duration=value' in query.\n");
  } else if (level.isNone() && duration.isSome()) {
    return http::BadRequest("Expecting 'level=value' in query.\n");
  }

  Try<int> v = numify<int>(level.get());

  if (v.isError()) {
    return http::BadRequest(v.error() + ".\n");
  }

  if (v.get() < 0) {
    return http::BadRequest(
        "Invalid level '" + stringify(v.get()) + "'.\n");
  } else if (v.get() < original) {
    return http::BadRequest(
        "'" + stringify(v.get()) + "' < original level.\n");
  }

  Try<Duration> d = Duration::parse(duration.get());

  if (d.isError()) {
    return http::BadRequest(d.error() + ".\n");
  }

  // Set the logging level.
  set(v.get());

  // Start a revert timer (if necessary).
  if (v.get() != original) {
    timeout = d.get();
    delay(timeout.remaining(), this, &This::revert);
  }

  return http::OK();
}


const std::string Logging::TOGGLE_HELP()
{
  return HELP(
    TLDR(
        "Sets the logging verbosity level for a specified duration."),
    DESCRIPTION(
        "The libprocess library uses [glog][glog] for logging. The library",
        "only uses verbose logging which means nothing will be output unless",
        "the verbosity level is set (by default it's 0, libprocess uses"
        "levels 1, 2, and 3).",
        "",
        "**NOTE:** If your application uses glog this will also affect",
        "your verbose logging.",
        "",
        "Query parameters:",
        "",
        ">        level=VALUE          Verbosity level (e.g., 1, 2, 3)",
        ">        duration=VALUE       Duration to keep verbosity level",
        ">                             toggled (e.g., 10secs, 15mins, etc.)"),
    REFERENCES(
        "[glog]: https://code.google.com/p/google-glog"));
}

} // namespace process {