// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

syntax = "proto2";

option optimize_for = LITE_RUNTIME;

package chrome_variations;

// This defines the Protocol Buffer representation of a Chrome Variations study
// as sent to clients of the Variations server.
//
// Next tag: 12
message Study {
  // The name of the study. Should not contain spaces or special characters.
  // Ex: "my_study"
  required string name = 1;

  // The expiry date of the study in Unix time format. (Seconds since midnight
  // January 1, 1970 UTC). See: http://en.wikipedia.org/wiki/Unix_time
  //
  // A study that has expired will be disabled, which will take precedence over
  // a corresponding hardcoded field trial in the client.
  //
  // Ex: 1330893974  (corresponds to 2012-03-04 20:46:14Z)
  optional int64 expiry_date = 3;

  // Consistency setting for a study.
  enum Consistency {
    SESSION = 0;  // Can't change within a session.
    PERMANENT = 1;  // Can't change for a given user.
  }

  // Consistency setting for this study. Optional - defaults to SESSION.
  // Ex: PERMANENT
  optional Consistency consistency = 7 [default = SESSION];

  // Name of the experiment that gets the default experience. This experiment
  // must be included in the list below.
  // Ex: "default"
  optional string default_experiment_name = 8;

  // An experiment within the study.
  //
  // Next tag: 4
  message Experiment {
    // The name of the experiment within the study.
    // Ex: "bucketA"
    required string name = 1;
    // The cut of the total probability taken for this group (the x in x / N,
    // where N is the sum of all x’s).
    // Ex: "50"
    required uint32 probability_weight = 2;
    // Optional id used to uniquely identify this experiment for Google web
    // properties.
    optional uint64 google_web_experiment_id = 3;
    // Optional id used to uniquely identify this experiment for Google Update.
    optional uint64 google_update_experiment_id = 4;
  }

  // List of experiments in this study. This list should include the default /
  // control group.
  //
  // For example, to specify that 99% of users get the default behavior, while
  // 0.5% of users get experience "A" and 0.5% of users get experience "B",
  // specify the values below.
  // Ex: { "default": 990, "A": 5, "B": 5 }
  repeated Experiment experiment = 9;

  // Possible Chrome release channels.
  // See: http://dev.chromium.org/getting-involved/dev-channel
  enum Channel {
    CANARY = 0;
    DEV = 1;
    BETA = 2;
    STABLE = 3;
  }

  // Possible Chrome operating system platforms.
  enum Platform {
    PLATFORM_WINDOWS  = 0;
    PLATFORM_MAC      = 1;
    PLATFORM_LINUX    = 2;
    PLATFORM_CHROMEOS = 3;
    PLATFORM_ANDROID  = 4;
    PLATFORM_IOS      = 5;
  }

  // Filtering criteria specifying whether this study is applicable to a given
  // Chrome instance.
  //
  // Next tag: 7
  message Filter {
    // The start date of the study in Unix time format. (Seconds since midnight
    // January 1, 1970 UTC). See: http://en.wikipedia.org/wiki/Unix_time
    // Ex: 1330893974  (corresponds to 2012-03-04 20:46:14Z)
    optional int64 start_date = 1;

    // The minimum Chrome version for this study, allowing a trailing '*'
    // character for pattern matching. Inclusive. (To check for a match, iterate
    // over each component checking >= until a * or end of string is reached.)
    // Optional - if not specified, there is no minimum version.
    // Ex: "17.0.963.46", "17.0.963.*", "17.*"
    optional string min_version = 2;

    // The maximum Chrome version for this study; same formatting as
    // |min_version| above. Inclusive. (To check for a match, iterate over each
    // component checking <= until a * or end of string is reached.)
    // Optional - if not specified, there is no maximum version.
    // Ex: "19.*"
    optional string max_version = 3;

    // List of channels that will receive this study. If omitted, the study
    // applies to all channels.
    // Ex: [BETA, STABLE]
    repeated Channel channel = 4;

    // List of platforms that will receive this study. If omitted, the study
    // applies to all platforms.
    // Ex: [PLATFORM_WINDOWS, PLATFORM_MAC]
    repeated Platform platform = 5;

    // List of locales that will receive this study. If omitted, the study
    // applies to all locales.
    // Ex: ["en-US", "en-CA"]
    repeated string locale = 6;
  }

  // Filtering criteria for this study. A study that is filtered out for a given
  // client is equivalent to that study not being sent at all.
  optional Filter filter = 10;

  // Randomization seed to be used when |consistency| is set to PERMANENT. If
  // not specified, randomization will be done using the trial name.
  optional uint32 randomization_seed = 11;
}