components/variations/proto/study.proto - chromium/src - Git at Google

 // 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 variations;

 // This defines the Protocol Buffer representation of a Chrome Variations study
 // as sent to clients of the Variations server.
 //
 // Next tag: 13
 message Study {
   // The name of the study. Should not contain spaces or special characters.
   // Ex: "my_study"
   required string name = 1;

   // DEPRECATED: Prefer end_date instead.
   // 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, and users will be assigned
   // groups based on the default_experiment_name. This 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. If not specified, a generic default
   // experiment name is used.
   // Ex: "default"
   optional string default_experiment_name = 8;

   // An experiment within the study.
   //
   // Next tag: 14
   message Experiment {
     // A named parameter value for this experiment.
     //
     // Next tag: 3
     message Param {
       // The name of the parameter.
       optional string name = 1;

       // The value of the parameter.
       optional string value = 2;
     }

     // The name of the experiment within the study.
     // Ex: "bucketA"
     required string name = 1;

     // The cut of the total probability taken for this experiment (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 allow this experiment to trigger experimental
     // behavior on Google web properties.
     optional uint64 google_web_trigger_experiment_id = 8;

     // Optional id used to uniquely identify this experiment for Chrome Sync.
     optional uint64 chrome_sync_experiment_id = 10;

     // Specifies the feature association parameters for this experiment group.
     //
     // Next tag: 5
     message FeatureAssociation {
       // Optional list of features to enable when this experiment is selected.
       // Command-line overrides take precedence over this setting. No feature
       // listed here should exist in the |disable_feature| list.
       repeated string enable_feature = 1;

       // Optional list of features to disable when this experiment is selected.
       // Command-line overrides take precedence over this setting. No feature
       // listed here should exist in the |enable_feature| list.
       repeated string disable_feature = 2;

       // Similar to |forcing_flag|, this is an optional name of a feature which
       // will cause this experiment to be activated, if that feature is enabled
       // from the command-line. Experiment with this set are not eligible for
       // selection via a random dice roll.
       // Mutually exclusive with |forcing_flag|, |forcing_feature_off| or
       // having a non-zero |probability_weight|.
       optional string forcing_feature_on = 3;

       // Similar to |forcing_flag|, this is an optional name of a feature which
       // will cause this experiment to be activated, if that feature is disabled
       // from the command-line. Experiment with this set are not eligible for
       // selection via a random dice roll.
       // Mutually exclusive with |forcing_flag|, |forcing_feature_on| or having
       // a non-zero |probability_weight|.
       optional string forcing_feature_off = 4;
     }
     optional FeatureAssociation feature_association = 12;

     // Optional name of a Chrome flag that, when present, causes this experiment
     // to be forced. If the forcing_flag field is set, users will not be
     // assigned to this experiment unless that flag is present in Chrome's
     // command line.
     // Mutually exclusive with |forcing_feature_on|, |forcing_feature_off| or
     // having a non-zero |probability_weight|.
     optional string forcing_flag = 5;

     // Parameter values for this experiment.
     repeated Param param = 6;

     enum Type {
       // Regular experiment group. This is the default value and can be omitted.
       NORMAL = 0;

       // Changes to this experiment group are ignored for the purposes of
       // kill-switch triggering. Included to allow the flexibility to not
       // trigger this logic for specific cases (e.g. a group rename without
       // any functionality changes).
       IGNORE_CHANGE = 1;

       // This is a kill-switch group that should be killed at "best effort"
       // priority, e.g. with a hot dog menu badge. The experiment must have a
       // probability_weight of 0.
       KILL_BEST_EFFORT = 2;

       // This is a kill-switch group that should be killed with "critical"
       // priority. Depending on platform this may result in showing a
       // non-dismissible restart prompt with a timer. This should only be used
       // in very serious emergency circumstances. The experiment must have a
       // probability_weight of 0.
       KILL_CRITICAL = 3;
     }
     optional Type type = 7 [default = NORMAL];

     // A UI string to override, and the new value to use.
     message OverrideUIString {
       // The first 32 bits of the MD5 hash digest of the resource name to
       // override.
       // e.g. Hash("IDS_BOOKMARK_BAR_UNDO")
       optional fixed32 name_hash = 1;

       // The new value of the string being overridden.
       // e.g. "Undo"
       optional string value = 2;
     }
     repeated OverrideUIString override_ui_string = 9;
   }

   // List of experiments in this study. This list should include the default /
   // control experiment.
   //
   // 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 {
     // UNKNOWN value is defined here for the benefit of code using this enum
     // type, but is not actually meant to be encoded in the protobuf.
     UNKNOWN = -1;
     CANARY = 0;
     DEV = 1;
     BETA = 2;
     STABLE = 3;
   }

   // Possible Chrome operating system platforms.
   // These names must match those in tools/variations/fieldtrial_to_struct.py.
   enum Platform {
     PLATFORM_WINDOWS         = 0;
     PLATFORM_MAC             = 1;
     PLATFORM_LINUX           = 2;
     PLATFORM_CHROMEOS        = 3;
     PLATFORM_ANDROID         = 4;
     PLATFORM_IOS             = 5;
     PLATFORM_ANDROID_WEBVIEW = 6;
     PLATFORM_FUCHSIA         = 7;
   }

   // Possible form factors Chrome is running on.
   enum FormFactor {
     // Chrome Desktop on Windows, Mac, Linux, or Chrome OS.
     DESKTOP = 0;
     // Phone-based mobile Chrome, e.g. an Android phone or iPhone.
     PHONE   = 1;
     // Tablet-based mobile Chrome, e.g. an Android tablet or iPad.
     TABLET  = 2;
     // Chrome OS running in single-app Kiosk mode.
     KIOSK   = 3;
   }

   // Filtering criteria specifying whether this study is applicable to a given
   // Chrome instance.
   //
   // Next tag: 16
   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 end 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)
     // Mutually exclusive with expiry_date. The difference between end_date and
     // expiry_date is that, when end_date is past, the field trial will not be
     // created. When expiry_date is past, the trial is still created, but will
     // be disabled, causing it to select its default group.
     optional int64 end_date = 13;

     // 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, unless |exclude_locale| is specified. Mutually
     // exclusive with |exclude_locale|.
     // Ex: ["en-US", "en-CA"]
     repeated string locale = 6;

     // List of locales that will be excluded from this study. If omitted, the
     // study applies to all locales unless |locale| is specified. Mutually
     // exclusive with |locale|.
     // Ex: ["en-US", "en-CA"]
     repeated string exclude_locale = 12;

     // List of form factors that will receive this study. If omitted, the study
     // applies to all form factors, unless |exclude_form_factor| is specified.
     // Mutually exclusive with |exclude_form_factor|.
     // Ex: [PHONE, TABLET]
     repeated FormFactor form_factor = 7;

     // List of form factors that will be excluded from this study. If omitted,
     // the study applies to all form factors unless |form_factor| is specified.
     // Mutually exclusive with |form_factor|.
     // Takes the same range of values as form_factor, e.g. [PHONE, TABLET].
     repeated FormFactor exclude_form_factor = 14;

     // List of Chrome OS hardware classes that will receive this study.
     //
     // Starting with Chrome M67, this does a case insensitive match on the same
     // hardware class field that is reported to UMA in the SystemProfileProto's
     // |hardware.hardware_class| field.
     //
     // Older versions did a case sensitive substring comparison, which was
     // problematic for short hardware classes like "eve" that existed as
     // substrings of other longer ones.
     //
     // If omitted, the study applies to all hardware classes unless
     // |exclude_hardware_class| is specified. Mutually exclusive with
     // |exclude_hardware_class|.
     // Ex: ["veyron_minnie", "daisy"]
     repeated string hardware_class = 8;

     // List of Chrome OS hardware classes that will be excluded in this study.
     //
     // Starting with Chrome M67, this does a case insensitive match on the same
     // hardware class field that is reported to UMA in the SystemProfileProto's
     // |hardware.hardware_class| field.
     //
     // Older versions did a case sensitive substring comparison, which was
     // problematic for short hardware classes like "eve" that existed as
     // substrings of other longer ones.
     //
     // If omitted, the study applies to all hardware classes unless
     // |hardware_class| is specified. Mutually exclusive with |hardware_class|.
     // Ex: ["veyron_minnie", "daisy"]
     repeated string exclude_hardware_class = 9;

     // List of lowercase ISO 3166-1 alpha-2 country codes that will receive this
     // study. If omitted, the study applies to all countries unless
     // |exclude_country| is specified. Mutually exclusive with
     // |exclude_country|.
     // Ex: ["in", "us"]
     repeated string country = 10;

     // List of lowercase ISO 3166-1 alpha-2 country codes that will be excluded
     // from this study. If omitted, the study applies to all countries unless
     // |country| is specified. Mutually exclusive with |country|.
     // Ex: ["in", "us"]
     repeated string exclude_country = 11;

     // Specifies whether the config should apply to low-end devices only. This
     // is currently only supported on Android.
     optional bool is_low_end_device = 15;
   }

   // 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;

   // Specifies whether the study starts as active initially, or whether it
   // requires the client to query its state before it is marked as active.
   enum ActivationType {
     // The study will be activated when its state is queried by the client.
     // This is recommended for most studies that include client code.
     ACTIVATION_EXPLICIT  = 0;
     // The study will be automatically activated when it is created. This
     // is recommended for studies that do not have any client logic.
     ACTIVATION_AUTO      = 1;
   }

   // Activation type for this study. Defaults to ACTIVATION_EXPLICIT if omitted.
   optional ActivationType activation_type = 12;
 }
	// 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 variations;

	// This defines the Protocol Buffer representation of a Chrome Variations study
	// as sent to clients of the Variations server.
	//
	// Next tag: 13
	message Study {
	// The name of the study. Should not contain spaces or special characters.
	// Ex: "my_study"
	required string name = 1;

	// DEPRECATED: Prefer end_date instead.
	// 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, and users will be assigned
	// groups based on the default_experiment_name. This 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. If not specified, a generic default
	// experiment name is used.
	// Ex: "default"
	optional string default_experiment_name = 8;

	// An experiment within the study.
	//
	// Next tag: 14
	message Experiment {
	// A named parameter value for this experiment.
	//
	// Next tag: 3
	message Param {
	// The name of the parameter.
	optional string name = 1;

	// The value of the parameter.
	optional string value = 2;
	}

	// The name of the experiment within the study.
	// Ex: "bucketA"
	required string name = 1;

	// The cut of the total probability taken for this experiment (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 allow this experiment to trigger experimental
	// behavior on Google web properties.
	optional uint64 google_web_trigger_experiment_id = 8;

	// Optional id used to uniquely identify this experiment for Chrome Sync.
	optional uint64 chrome_sync_experiment_id = 10;

	// Specifies the feature association parameters for this experiment group.
	//
	// Next tag: 5
	message FeatureAssociation {
	// Optional list of features to enable when this experiment is selected.
	// Command-line overrides take precedence over this setting. No feature
	// listed here should exist in the \|disable_feature\| list.
	repeated string enable_feature = 1;

	// Optional list of features to disable when this experiment is selected.
	// Command-line overrides take precedence over this setting. No feature
	// listed here should exist in the \|enable_feature\| list.
	repeated string disable_feature = 2;

	// Similar to \|forcing_flag\|, this is an optional name of a feature which
	// will cause this experiment to be activated, if that feature is enabled
	// from the command-line. Experiment with this set are not eligible for
	// selection via a random dice roll.
	// Mutually exclusive with \|forcing_flag\|, \|forcing_feature_off\| or
	// having a non-zero \|probability_weight\|.
	optional string forcing_feature_on = 3;

	// Similar to \|forcing_flag\|, this is an optional name of a feature which
	// will cause this experiment to be activated, if that feature is disabled
	// from the command-line. Experiment with this set are not eligible for
	// selection via a random dice roll.
	// Mutually exclusive with \|forcing_flag\|, \|forcing_feature_on\| or having
	// a non-zero \|probability_weight\|.
	optional string forcing_feature_off = 4;
	}
	optional FeatureAssociation feature_association = 12;

	// Optional name of a Chrome flag that, when present, causes this experiment
	// to be forced. If the forcing_flag field is set, users will not be
	// assigned to this experiment unless that flag is present in Chrome's
	// command line.
	// Mutually exclusive with \|forcing_feature_on\|, \|forcing_feature_off\| or
	// having a non-zero \|probability_weight\|.
	optional string forcing_flag = 5;

	// Parameter values for this experiment.
	repeated Param param = 6;

	enum Type {
	// Regular experiment group. This is the default value and can be omitted.
	NORMAL = 0;

	// Changes to this experiment group are ignored for the purposes of
	// kill-switch triggering. Included to allow the flexibility to not
	// trigger this logic for specific cases (e.g. a group rename without
	// any functionality changes).
	IGNORE_CHANGE = 1;

	// This is a kill-switch group that should be killed at "best effort"
	// priority, e.g. with a hot dog menu badge. The experiment must have a
	// probability_weight of 0.
	KILL_BEST_EFFORT = 2;

	// This is a kill-switch group that should be killed with "critical"
	// priority. Depending on platform this may result in showing a
	// non-dismissible restart prompt with a timer. This should only be used
	// in very serious emergency circumstances. The experiment must have a
	// probability_weight of 0.
	KILL_CRITICAL = 3;
	}
	optional Type type = 7 [default = NORMAL];

	// A UI string to override, and the new value to use.
	message OverrideUIString {
	// The first 32 bits of the MD5 hash digest of the resource name to
	// override.
	// e.g. Hash("IDS_BOOKMARK_BAR_UNDO")
	optional fixed32 name_hash = 1;

	// The new value of the string being overridden.
	// e.g. "Undo"
	optional string value = 2;
	}
	repeated OverrideUIString override_ui_string = 9;
	}

	// List of experiments in this study. This list should include the default /
	// control experiment.
	//
	// 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 {
	// UNKNOWN value is defined here for the benefit of code using this enum
	// type, but is not actually meant to be encoded in the protobuf.
	UNKNOWN = -1;
	CANARY = 0;
	DEV = 1;
	BETA = 2;
	STABLE = 3;
	}

	// Possible Chrome operating system platforms.
	// These names must match those in tools/variations/fieldtrial_to_struct.py.
	enum Platform {
	PLATFORM_WINDOWS = 0;
	PLATFORM_MAC = 1;
	PLATFORM_LINUX = 2;
	PLATFORM_CHROMEOS = 3;
	PLATFORM_ANDROID = 4;
	PLATFORM_IOS = 5;
	PLATFORM_ANDROID_WEBVIEW = 6;
	PLATFORM_FUCHSIA = 7;
	}

	// Possible form factors Chrome is running on.
	enum FormFactor {
	// Chrome Desktop on Windows, Mac, Linux, or Chrome OS.
	DESKTOP = 0;
	// Phone-based mobile Chrome, e.g. an Android phone or iPhone.
	PHONE = 1;
	// Tablet-based mobile Chrome, e.g. an Android tablet or iPad.
	TABLET = 2;
	// Chrome OS running in single-app Kiosk mode.
	KIOSK = 3;
	}

	// Filtering criteria specifying whether this study is applicable to a given
	// Chrome instance.
	//
	// Next tag: 16
	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 end 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)
	// Mutually exclusive with expiry_date. The difference between end_date and
	// expiry_date is that, when end_date is past, the field trial will not be
	// created. When expiry_date is past, the trial is still created, but will
	// be disabled, causing it to select its default group.
	optional int64 end_date = 13;

	// 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, unless \|exclude_locale\| is specified. Mutually
	// exclusive with \|exclude_locale\|.
	// Ex: ["en-US", "en-CA"]
	repeated string locale = 6;

	// List of locales that will be excluded from this study. If omitted, the
	// study applies to all locales unless \|locale\| is specified. Mutually
	// exclusive with \|locale\|.
	// Ex: ["en-US", "en-CA"]
	repeated string exclude_locale = 12;

	// List of form factors that will receive this study. If omitted, the study
	// applies to all form factors, unless \|exclude_form_factor\| is specified.
	// Mutually exclusive with \|exclude_form_factor\|.
	// Ex: [PHONE, TABLET]
	repeated FormFactor form_factor = 7;

	// List of form factors that will be excluded from this study. If omitted,
	// the study applies to all form factors unless \|form_factor\| is specified.
	// Mutually exclusive with \|form_factor\|.
	// Takes the same range of values as form_factor, e.g. [PHONE, TABLET].
	repeated FormFactor exclude_form_factor = 14;

	// List of Chrome OS hardware classes that will receive this study.
	//
	// Starting with Chrome M67, this does a case insensitive match on the same
	// hardware class field that is reported to UMA in the SystemProfileProto's
	// \|hardware.hardware_class\| field.
	//
	// Older versions did a case sensitive substring comparison, which was
	// problematic for short hardware classes like "eve" that existed as
	// substrings of other longer ones.
	//
	// If omitted, the study applies to all hardware classes unless
	// \|exclude_hardware_class\| is specified. Mutually exclusive with
	// \|exclude_hardware_class\|.
	// Ex: ["veyron_minnie", "daisy"]
	repeated string hardware_class = 8;

	// List of Chrome OS hardware classes that will be excluded in this study.
	//
	// Starting with Chrome M67, this does a case insensitive match on the same
	// hardware class field that is reported to UMA in the SystemProfileProto's
	// \|hardware.hardware_class\| field.
	//
	// Older versions did a case sensitive substring comparison, which was
	// problematic for short hardware classes like "eve" that existed as
	// substrings of other longer ones.
	//
	// If omitted, the study applies to all hardware classes unless
	// \|hardware_class\| is specified. Mutually exclusive with \|hardware_class\|.
	// Ex: ["veyron_minnie", "daisy"]
	repeated string exclude_hardware_class = 9;

	// List of lowercase ISO 3166-1 alpha-2 country codes that will receive this
	// study. If omitted, the study applies to all countries unless
	// \|exclude_country\| is specified. Mutually exclusive with
	// \|exclude_country\|.
	// Ex: ["in", "us"]
	repeated string country = 10;

	// List of lowercase ISO 3166-1 alpha-2 country codes that will be excluded
	// from this study. If omitted, the study applies to all countries unless
	// \|country\| is specified. Mutually exclusive with \|country\|.
	// Ex: ["in", "us"]
	repeated string exclude_country = 11;

	// Specifies whether the config should apply to low-end devices only. This
	// is currently only supported on Android.
	optional bool is_low_end_device = 15;
	}

	// 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;

	// Specifies whether the study starts as active initially, or whether it
	// requires the client to query its state before it is marked as active.
	enum ActivationType {
	// The study will be activated when its state is queried by the client.
	// This is recommended for most studies that include client code.
	ACTIVATION_EXPLICIT = 0;
	// The study will be automatically activated when it is created. This
	// is recommended for studies that do not have any client logic.
	ACTIVATION_AUTO = 1;
	}

	// Activation type for this study. Defaults to ACTIVATION_EXPLICIT if omitted.
	optional ActivationType activation_type = 12;
	}