config

type Attribute struct {
	Key   string `mapstructure:"key"`
	Value any    `mapstructure:"value"`
}

type Config struct {
	// Directory is the data directory used by the database to store files.
	// If the directory is empty in-memory storage is used.
	Directory string `mapstructure:"directory"`

	// PassThrough is a configuration that determines whether summary
	// metrics should be passed through as they are or aggregated. This
	// is because they lead to lossy aggregations.
	PassThrough PassThrough `mapstructure:"pass_through"`

	// Intervals is a list of interval configuration that the processor
	// will aggregate over. The interval duration must be in increasing
	// order and must be a factor of the smallest interval duration.
	// TODO (lahsivjar): Make specifying interval easier. We can just
	// optimize the timer to run on differnt times and remove any
	// restriction on different interval configuration.
	Intervals []IntervalConfig `mapstructure:"intervals"`

	// MetadataKeys is a list of client.Metadata keys that will be
	// propagated through the metrics aggregated by the processor.
	//
	// Only the listed metadata keys will be propagated to the
	// resulting metrics.
	//
	// Entries are case-insensitive. Duplicated entries will
	// trigger a validation error.
	MetadataKeys []string `mapstructure:"metadata_keys"`

	ResourceLimit  LimitConfig `mapstructure:"resource_limit"`
	ScopeLimit     LimitConfig `mapstructure:"scope_limit"`
	MetricLimit    LimitConfig `mapstructure:"metric_limit"`
	DatapointLimit LimitConfig `mapstructure:"datapoint_limit"`

	// ExponentialHistogramMaxBuckets sets the maximum number of buckets
	// to use for resulting exponential histograms from merge operations.
	// This allows to bound the maximum number of buckets used by the
	// exponential histograms which could be huge if histograms with
	// precisions ranging in, say, minutes and milliseconds are merged
	// together. Defaults to 160.
	ExponentialHistogramMaxBuckets int `mapstructure:"exponential_histogram_max_buckets"`
}

type IntervalConfig struct {
	Duration time.Duration `mapstructure:"duration"`
	// Statements are a list of OTTL statements to be executed on the
	// metrics produced for a given interval. The list of available
	// OTTL paths for datapoints can be checked at:
	// https://pkg.go.dev/github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl/contexts/ottldatapoint#section-readme
	// The list of available OTTL editors can be checked at:
	// https://pkg.go.dev/github.com/open-telemetry/opentelemetry-collector-contrib/pkg/ottl/ottlfuncs#section-readme
	Statements []string `mapstructure:"statements"`
}

type LimitConfig struct {
	MaxCardinality int64          `mapstructure:"max_cardinality"`
	Overflow       OverflowConfig `mapstructure:"overflow"`
}

type OverflowConfig struct {
	// Attributes are added to the overflow bucket for the respective
	// limit. For example, attributes defined for an overflow config
	// representing a scope will be added to the overflow scope attributes.
	Attributes []Attribute `mapstructure:"attributes"`
}

type PassThrough struct {
	// Summary is a flag that determines whether summary metrics should
	// be passed through as they are or aggregated. Since summaries don't
	// have an associated temporality, we assume that summaries are
	// always cumulative.
	Summary bool `mapstructure:"summary"`
}