// Copyright 2016 The Fuchsia 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.

syntax = "proto3";

package cobalt.shuffler;

option go_package = "shuffler";

////////////////////////////////////////////////////////////////////////////
// Messages that describe the shuffler configuration. A global configuration
// is provided that is applicable to all metrics.
////////////////////////////////////////////////////////////////////////////

message Policy {
  // Specifies Shuffler's dispatch frequency in hours. For example, if
  // |frequency_in_hours| is 48 then every two days the Shuffler will send
  // Observations to the Analyzer.
  uint32 frequency_in_hours = 1;

  // Specifies the probability of dropping random incoming observations from
  // Encoder clients before being persisted on Shuffler. For example, if
  // p=0.25 then each observation would have a 25% chance of being dropped.
  // It should be a value in the range [0.0, 1.0]. A dropped observation will
  // not count towards the threshold.
  float p_observation_drop = 2;

  // The minimum number of Observations that must be present in a batch
  // before the Shuffler will dispatch that batch to the Analyzer.
  //
  // A batch consists of a collection of Observations that all have the
  // same |ObservationMetadata| i.e., (metric_id, day_index). The Shuffler
  // dispatches Observations to the Analyzer on a per-batch basis.
  // For each batch if the size of that batch is at least |threshold| then
  // the Observations in that batch will be dispatched to the Analyzer and
  // deleted from the Shuffler.
  //
  // For each batch whose contents are not dispatched to the Analyzer
  // because the batch size is too small, the Shuffler will delete those
  // Observations from the batch whose age is at least |disposal_age_days|.
  uint32 threshold = 3;

  // The URL of the Analyzer.
  string analyzer_url = 4;

  // An Observation that has not been dispatched to the Analyzer will be
  // discarded after it has been present on the Shuffler for this many
  // days.
  uint32 disposal_age_days = 5;
}

// Provides configuration parameters for Shuffler. An instance of
// ShufflerConfig is deserialized from a text file.
message ShufflerConfig {
  Policy global_config = 1;
}