// Copyright 2018 The Fuchsia 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 = "proto3";

package cobalt;

import "src/registry/report_definition.proto";

option go_package = "src/registry;config";

// A Metric is a category of Events that a user logs to Cobalt.
//
// A Metric belongs to a Project and has a name and a type.
//
// When an Event is logged in Cobalt's Logger interface, a Metric is
// specified and the Event then belongs to that Metric.
//
// A MetricDefinition includes a list of ReportDefinitions. These are the
// definitions of the Reports that should be run for that Metric. Generating a
// Report involves the Cobalt client sending Observations to the server based
// on the Events belonging to the Metric, and the server performing an analysis
// of those Observations in order to generate the Report output.
//
// When an Observation is sent from a Cobalt client to the server, it contains
// a Metric id and a Report id. This indicates that the
// Observation is derived from the Events belonging to the Metric for the
// purpose of generating the Report.
//
// A MetricDefinition is used to define a Metric.
//
// Next ID: 27
message MetricDefinition {
  reserved 6, 7, 9, 13, 14, 15, 17, 21, 23, 24;
  reserved "event_codes", "event_code_buffer_max", "max_event_code", "parts",
      "proto_name", "string_buffer_max", "replacement_metric_id",
      "no_replacement_metric", "customer_name", "project_name";

  // Unique name for this Metric within its owning project.
  // The name must obey the syntax of a C variable name and must have length
  // at most 64.
  string metric_name = 1;

  // These three numbers form this Metric's unique numerical ID in Cobalt. The
  // Cobalt registry YAML parser will automatically set the value of
  // customer_id and project_id based on the context of the YAML file.
  // The user must manually set the |id| field to a number uniquely identifying
  // this Metric within its project.
  uint32 customer_id = 2;
  uint32 project_id = 3;
  uint32 id = 4;

  // A Metric has one of the following types.
  // Next ID: 12
  enum MetricType {
    reserved 1, 2, 3, 4, 5, 6, 7, 9999;
    reserved "CUSTOM", "ELAPSED_TIME", "EVENT_COUNT", "EVENT_OCCURRED",
        "FRAME_RATE", "INT_HISTOGRAM", "MEMORY_USAGE", "STRING_USED";

    UNSET = 0;

    // Records that an event has occurred one or many times.
    //
    // MetricDefinition fields:
    // - metric_dimensions (0 or more)
    // - metric_semantics (required)
    OCCURRENCE = 8;

    // Records an integer measurement.
    //
    // MetricDefinition fields:
    // - metric_dimensions (0 or more)
    // - metric_units (Either this field or metric_units_other is required.)
    // - metric_units_other (Either metric_units or this field is required.)
    // - metric_semantics (required)
    INTEGER = 9;

    // Records many approximate integer measurements.
    //
    // MetricDefinition fields:
    // - metric_dimensions (0 or more)
    // - int_buckets
    // - metric_units (Either this field or metric_units other is required.)
    // - metric_units_other (Either metric_units or this field is required.)
    // - metric_semantics (required)
    INTEGER_HISTOGRAM = 10;

    // Records the fact that a string was observed.
    //
    // MetricDefinition fields:
    // - metric_dimensions (0 or more)
    // - metric_semantics (required)
    // - string_candidate_file. (required)
    STRING = 11;
  }

  MetricType metric_type = 5;

  // A container for enumerated sets of event codes.
  message MetricDimension {
    // Name of the dimension. Used only in the generated library for the names
    // of the constants.
    string dimension = 1;

    // The enumerated set of event codes for this dimension.
    //
    // The keys are the numeric codes and the values are the
    // human-readable labels for the codes. It is OK to add new elements to this
    // map or to change the spelling of labels after data collection has
    // started. It is not OK to change the meaning of any of the codes.
    //
    // If an event code for a dimension is not passed to the Cobalt logger for
    // an event that occurred, the value zero will be used. Therefore, it is
    // not recommended to associate the zero event code with a meaningful
    // label. Instead, omit the zero event code and your reports will contain
    // event code labels of `<code 0>` when the event code was not specified,
    // or specify an explicit zero value with a label of `Unknown` or `Unset`.
    map<uint32, string> event_codes = 2;

    // max_event_code is the maximal value for any event in this dimension.
    // Subject to the following rules:
    //
    // 1. If you specify max_event_code, you cannot use a value greater than
    //    that.
    // 2. If you do not specify max_event_code, you can only use one of the
    //    explicitly registered values (event_codes).
    // 3. For the purposes of validation, each dimension is assigned a number
    //    which is equal to max_event_code+1 if max_event_code is set, or else
    //    equal to the number of registered values. The product of all of these
    //    values must not exceed 1024.
    // 4. Adding, removing, or changing max_event_code is allowed so long as the
    //    above rules are not violated.
    uint32 max_event_code = 3;

    reserved 4;
    reserved "also_treat_as_legacy";

    // event_code_aliases is used by the code generator to generate additional
    // enum variants. This is intended as a temporary step to allow a soft
    // cross-repo rename of an event_code variant, and should be cleaned up as
    // soon as possible.
    //
    // The expected use case is as follows (config abbridged for clarity):
    //
    // Step 1: Have a metric
    //
    //   event_codes:
    //     - 1: BadName
    //
    // Step 2: Rename an event code, adding an alias
    //
    //   event_codes:
    //     - 1: GoodName
    //   event_code_aliases:
    //     GoodName: BadName
    //
    // Step 3: After all references to `BadName` are removed
    //
    //   event_codes:
    //     - 1: GoodName
    //
    map<string, string> event_code_aliases = 5;
  }

  // A list of MetricDimensions.
  //
  // This field is used in most Metric types.
  repeated MetricDimension metric_dimensions = 16;

  // For metrics of types INTEGER and INTEGER_HISTOGRAM, specifies the units of
  // the integer. Either metric_units or metric_units_other must be specified.
  // Use metric_units_other if none of the pre-defined MetricUnits are
  // appropriate.
  MetricUnits metric_units = 18;
  string metric_units_other = 19;

  // Specifies a list of pre-defined semantic categories for the metric.
  // This should augment the description given in the comments.
  repeated MetricSemantics metric_semantics = 20;

  // The path to a list of candidate strings for a metric of type STRING.
  // The path should be relative to the root of the Cobalt registry, for
  // instance "fuchsia/test_app2/application_names.txt". String candidate
  // files should ideally be placed in the same registry and directory as the
  // project that uses it.
  //
  // This is a required field for metrics of type STRING.
  string string_candidate_file = 22;

  // The set of buckets for the histograms for this metric. This field is used
  // only with metrics of type INTEGER_HISTOGRAM.
  IntegerBuckets int_buckets = 8;

  /////////// The rest of the fields are used with all Metric types ///////////

  // A TimeZonePolicy specifies how the day index of an Event should be computed
  // based on the system time when the Event is logged.
  enum TimeZonePolicy {
    // Use the date in UTC at logging time to compute the day index.
    UTC = 0;

    // Use the device-local date at logging time to compute the day index.
    LOCAL = 1;

    // Use the time zone specified in the `other_time_zone` field to compute the
    // day index.
    OTHER_TIME_ZONE = 2;
  }

  // The TimeZonePolicy for this Metric (Optional. Defaults to UTC)
  TimeZonePolicy time_zone_policy = 10;

  // An IANA time zone identifier (https://iana.org/time-zones). Should be set
  // if and only if the metric's `time_zone_policy` is OTHER_TIME_ZONE.
  string other_time_zone = 25;

  message Metadata {
    reserved 2;
    reserved "owner";

    // The date after which this metric is no longer valid. If this field is not
    // supplied, the metric is considered currently expired, and is not
    // guaranteed to be reported by cobalt.
    //
    // The date must be expressed in yyyy/mm/dd form.
    // It may be at most one year in the future.
    string expiration_date = 1;

    // Maximum ReleaseStage for which this Metric is allowed to be collected.
    ReleaseStage max_release_stage = 4;

    // If 'also_log_locally' is true, Cobalt will log it when it receives events
    // associated with this metric.
    bool also_log_locally = 5;
  }
  Metadata meta_data = 11;

  // The Reports to run for this Metric.
  repeated ReportDefinition reports = 12;

  // Report IDs that have been previously used and deleted from this metric.
  // These IDs must not be reused in new reports.
  repeated uint32 deleted_report_ids = 26;
}

enum MetricUnits {
  METRIC_UNITS_OTHER = 0;

  // Units of time
  NANOSECONDS = 1;
  MICROSECONDS = 2;
  MILLISECONDS = 3;
  SECONDS = 4;
  MINUTES = 5;

  // Units of data size
  BYTES = 6;
  KIBIBYTES = 7;   // 2^10 bytes
  KILOBYTES = 8;   // 10^3 bytes
  MEBIBYTES = 9;   // 2^20 bytes
  MEGABYTES = 10;  // 10^6 bytes
}

enum MetricSemantics {
  METRIC_SEMANTICS_UNSPECIFIED = 0;

  // The metric measure how much CPU is being used.
  CPU = 1;

  // The metric measures size of a data structure.
  DATA_SIZE = 2;

  // The metric measures frame rendering performance.
  FRAME_RENDERING = 3;

  // The metric measures the latency of an operation.
  LATENCY = 4;

  // The metric measures the amount of memory being used.
  MEMORY_USAGE = 5;

  // The metric measures something about the devices network communication.
  NETWORK_COMMUNICATION = 6;

  // The metric is being used to measure some property of the real world
  // environment outside of the device.
  OUTSIDE_ENVIRONMENT = 7;

  // The metric is being used to track how often a feature or system is used.
  USAGE_COUNTING = 8;
}