Copyright	(c) Ian Duncan 2024-2026
License	BSD-3
Stability	experimental
Safe Haskell	Safe-Inferred
Language	Haskell2010

OpenTelemetry.Environment

Description

Helpers for reading OpenTelemetry environment variables that control exporter selection, metric export intervals, exemplar filters, and log exporter choice. Used by the SDK during provider initialization.

Synopsis

lookupBooleanEnv :: String -> IO Bool
readEnv :: Read a => String -> IO (Maybe a)
readEnvDefault :: Read a => String -> a -> IO a
readEnvDefaultWithAlias :: Read a => String -> String -> a -> IO a
data MetricsExporterSelection
lookupMetricsExporterSelection :: IO (Maybe MetricsExporterSelection)
lookupMetricExportIntervalMillis :: IO (Maybe Int)
lookupMetricExportTimeoutMillis :: IO (Maybe Int)
data MetricsExemplarFilter
lookupMetricsExemplarFilter :: IO (Maybe MetricsExemplarFilter)
data LogsExporterSelection
lookupLogsExporterSelection :: IO (Maybe LogsExporterSelection)

Documentation

lookupBooleanEnv :: String -> IO Bool Source #

readEnv :: Read a => String -> IO (Maybe a) Source #

Read an environment variable and parse it with readMaybe. Returns Nothing if unset or unparseable.

readEnvDefault :: Read a => String -> a -> IO a Source #

Like readEnv but falls back to a default value if the variable is unset or unparseable.

readEnvDefaultWithAlias :: Read a => String -> String -> a -> IO a Source #

Like readEnvDefault but tries a primary key first, then a legacy alias. Useful when an env var was renamed to maintain backwards compatibility.

data MetricsExporterSelection Source #

Parsed value of OTEL_METRICS_EXPORTER (first entry if comma-separated). See https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/#exporter-selection.

Constructors

MetricsExporterNone
MetricsExporterOtlp
MetricsExporterPrometheus
MetricsExporterConsole
MetricsExporterCustom !String	A name not in the built-in set; looked up via the exporter registry.

Instances

Instances details

Show MetricsExporterSelection Source #
Instance details Defined in OpenTelemetry.Environment Methods showsPrec :: Int -> MetricsExporterSelection -> ShowS # show :: MetricsExporterSelection -> String # showList :: [MetricsExporterSelection] -> ShowS #
Eq MetricsExporterSelection Source #
Instance details Defined in OpenTelemetry.Environment Methods (==) :: MetricsExporterSelection -> MetricsExporterSelection -> Bool # (/=) :: MetricsExporterSelection -> MetricsExporterSelection -> Bool #

lookupMetricsExporterSelection :: IO (Maybe MetricsExporterSelection) Source #

Read OTEL_METRICS_EXPORTER. Unknown or empty values return Nothing (caller may default to OTLP).

lookupMetricExportIntervalMillis :: IO (Maybe Int) Source #

Read OTEL_METRIC_EXPORT_INTERVAL (milliseconds between periodic export cycles). See https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/.

lookupMetricExportTimeoutMillis :: IO (Maybe Int) Source #

Read OTEL_METRIC_EXPORT_TIMEOUT (milliseconds allowed per export call). See https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/.

data MetricsExemplarFilter Source #

Parsed OTEL_METRICS_EXEMPLAR_FILTER (when present).

Constructors

MetricsExemplarFilterTraceBased
MetricsExemplarFilterAlwaysOn
MetricsExemplarFilterAlwaysOff

Instances

Instances details

Show MetricsExemplarFilter Source #
Instance details Defined in OpenTelemetry.Environment Methods showsPrec :: Int -> MetricsExemplarFilter -> ShowS # show :: MetricsExemplarFilter -> String # showList :: [MetricsExemplarFilter] -> ShowS #
Eq MetricsExemplarFilter Source #
Instance details Defined in OpenTelemetry.Environment Methods (==) :: MetricsExemplarFilter -> MetricsExemplarFilter -> Bool # (/=) :: MetricsExemplarFilter -> MetricsExemplarFilter -> Bool #

lookupMetricsExemplarFilter :: IO (Maybe MetricsExemplarFilter) Source #

Read OTEL_METRICS_EXEMPLAR_FILTER (first segment if comma-separated). Unknown values return Nothing.

data LogsExporterSelection Source #

Parsed value of OTEL_LOGS_EXPORTER (first entry if comma-separated). See https://opentelemetry.io/docs/specs/otel/configuration/sdk-environment-variables/#exporter-selection.

Since: 0.4.0.0

Constructors

LogsExporterNone
LogsExporterOtlp
LogsExporterConsole
LogsExporterCustom !String	A name not in the built-in set; looked up via the exporter registry.

Instances

Instances details

Show LogsExporterSelection Source #
Instance details Defined in OpenTelemetry.Environment Methods showsPrec :: Int -> LogsExporterSelection -> ShowS # show :: LogsExporterSelection -> String # showList :: [LogsExporterSelection] -> ShowS #
Eq LogsExporterSelection Source #
Instance details Defined in OpenTelemetry.Environment Methods (==) :: LogsExporterSelection -> LogsExporterSelection -> Bool # (/=) :: LogsExporterSelection -> LogsExporterSelection -> Bool #

lookupLogsExporterSelection :: IO (Maybe LogsExporterSelection) Source #

Read OTEL_LOGS_EXPORTER. Empty values return Nothing (caller defaults to OTLP). Unknown names are returned as LogsExporterCustom for registry lookup.