// Copyright The OpenTelemetry Authors // SPDX-License-Identifier: Apache-2.0 #pragma once #include #include #include #include "opentelemetry/metrics/provider.h" #include "opentelemetry/nostd/string_view.h" #include "opentelemetry/sdk/metrics/meter.h" #include "opentelemetry/version.h" OPENTELEMETRY_BEGIN_NAMESPACE namespace exporter { namespace metrics { /** * The Prometheus Utils contains utility functions for Prometheus Exporter */ class PrometheusExporterUtils { public: /** * Helper function to convert OpenTelemetry metrics data collection * to Prometheus metrics data collection * * @param records a collection of metrics in OpenTelemetry * @param populate_target_info whether to populate target_info * @param without_otel_scope whether to populate otel_scope_name and otel_scope_version * attributes * @param without_units exporter configuration controlling whether to append unit suffix in * the exported metrics. * @param without_type_suffix exporter configuration controlling whether to append type suffix in * the exported metrics. * @return a collection of translated metrics that is acceptable by Prometheus */ static std::vector<::prometheus::MetricFamily> TranslateToPrometheus( const sdk::metrics::ResourceMetrics &data, bool populate_target_info = true, bool without_otel_scope = false, bool without_units = false, bool without_type_suffix = false); private: /** * Sanitize the given metric name or label according to Prometheus rule. * * This function is needed because names in OpenTelemetry can contain * alphanumeric characters, '_', '.', and '-', whereas in Prometheus the * name should only contain alphanumeric characters and '_'. * @param name name */ static std::string SanitizeNames(std::string name); /** * Sanitize the given metric name or label according to Prometheus rule. * * @param name label name * @param value label value * @param labels target labels */ static void AddPrometheusLabel(std::string name, std::string value, std::vector<::prometheus::ClientMetric::Label> *labels); static std::string MapToPrometheusName(const std::string &name, const std::string &unit, ::prometheus::MetricType prometheus_type, bool without_units, bool without_type_suffix); /** * A utility function that returns the equivalent Prometheus name for the provided OTLP metric * unit. * * @param raw_metric_unitName The raw metric unit for which Prometheus metric unit needs to be * computed. * @return the computed Prometheus metric unit equivalent of the OTLP metric unit */ static std::string GetEquivalentPrometheusUnit(const std::string &raw_metric_unitName); /** * This method retrieves the expanded Prometheus unit name for known abbreviations. OTLP metrics * use the c/s notation as specified at UCUM. The list of * mappings is adopted from OpenTelemetry * Collector Contrib. * * @param unit_abbreviation The unit that name that needs to be expanded/converted to Prometheus * units. * @return The expanded/converted unit name if known, otherwise returns the input unit name as-is. */ static std::string GetPrometheusUnit(const std::string &unit_abbreviation); /** * This method retrieves the expanded Prometheus unit name to be used with "per" units for known * units. For example: s => per second (singular) * * @param per_unit_abbreviation The unit abbreviation used in a 'per' unit. * @return The expanded unit equivalent to be used in 'per' unit if the input is a known unit, * otherwise returns the input as-is. */ static std::string GetPrometheusPerUnit(const std::string &per_unit_abbreviation); /** * Replaces all characters that are not a letter or a digit with '_' to make the resulting string * Prometheus compliant. This method also removes leading and trailing underscores - this is done * to keep the resulting unit similar to what is produced from the collector's implementation. * * @param str The string input that needs to be made Prometheus compliant. * @return the cleaned-up Prometheus compliant string. */ static std::string CleanUpString(const std::string &str); /** * This method is used to convert the units expressed as a rate via '/' symbol in their name to * their expanded text equivalent. For instance, km/h => km_per_hour. The method operates on the * input by splitting it in 2 parts - before and after '/' symbol and will attempt to expand any * known unit abbreviation in both parts. Unknown abbreviations & unsupported characters will * remain unchanged in the final output of this function. * * @param rate_expressed_unit The rate unit input that needs to be converted to its text * equivalent. * @return The text equivalent of unit expressed as rate. If the input does not contain '/', the * function returns it as-is. */ static std::string ConvertRateExpressedToPrometheusUnit(const std::string &rate_expressed_unit); /** * This method drops all characters enclosed within '{}' (including the curly braces) by replacing * them with an empty string. Note that this method will not produce the intended effect if there * are nested curly braces within the outer enclosure of '{}'. * *

For instance, {packet{s}s} => s}. * * @param unit The input unit from which text within curly braces needs to be removed. * @return The resulting unit after removing the text within '{}'. */ static std::string RemoveUnitPortionInBraces(const std::string &unit); static opentelemetry::sdk::metrics::AggregationType getAggregationType( const opentelemetry::sdk::metrics::PointType &point_type); /** * Translate the OTel metric type to Prometheus metric type */ static ::prometheus::MetricType TranslateType(opentelemetry::sdk::metrics::AggregationType kind, bool is_monotonic = true); /** * Add a target_info metric to collect resource attributes */ static void SetTarget(const sdk::metrics::ResourceMetrics &data, const opentelemetry::sdk::instrumentationscope::InstrumentationScope *scope, std::vector<::prometheus::MetricFamily> *output); /** * Set metric data for: * Counter => Prometheus Counter */ template static void SetData(const std::vector &values, const opentelemetry::sdk::metrics::PointAttributes &labels, const opentelemetry::sdk::instrumentationscope::InstrumentationScope *scope, ::prometheus::MetricType type, ::prometheus::MetricFamily *metric_family, const opentelemetry::sdk::resource::Resource *resource); /** * Set metric data for: * Histogram => Prometheus Histogram */ template static void SetData(const std::vector &values, const std::vector &boundaries, const std::vector &counts, const opentelemetry::sdk::metrics::PointAttributes &labels, const opentelemetry::sdk::instrumentationscope::InstrumentationScope *scope, ::prometheus::MetricFamily *metric_family, const opentelemetry::sdk::resource::Resource *resource); /** * Set time and labels to metric data */ static void SetMetricBasic( ::prometheus::ClientMetric &metric, const opentelemetry::sdk::metrics::PointAttributes &labels, const opentelemetry::sdk::instrumentationscope::InstrumentationScope *scope, const opentelemetry::sdk::resource::Resource *resource); /** * Convert attribute value to string */ static std::string AttributeValueToString( const opentelemetry::sdk::common::OwnedAttributeValue &value); /** * Handle Counter and Gauge. */ template static void SetValue(const std::vector &values, ::prometheus::MetricType type, ::prometheus::ClientMetric *metric); /** * Handle Gauge from MinMaxSumCount */ static void SetValue(double value, ::prometheus::ClientMetric *metric); /** * Handle Histogram */ template static void SetValue(const std::vector &values, const std::vector &boundaries, const std::vector &counts, ::prometheus::ClientMetric *metric); // For testing friend class SanitizeNameTester; }; } // namespace metrics } // namespace exporter OPENTELEMETRY_END_NAMESPACE