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#OpenTelemetry Logs SDK

This package implements the SDK objects needed to produce and export log records.

#Main types

  • SdkLoggerProvider: owns shared resource and processor configuration
  • SdkLogger: creates scoped log records
  • LogRecord: immutable exported log payload
  • BatchConfig: queue and timing configuration for batch export
  • LogProcessor: processing hook interface
  • SimpleLogProcessor, BatchLogProcessor: processor implementations
  • LogExporter: exporter callback wrapper
  • InMemoryLogExporter: test helper

#Processing model

Async SdkLogger::emit() snapshots the current provider resource and instrumentation scope into a LogRecord, then forwards that record through every configured processor.

BatchLogProcessor buffers records in memory. When the queue reaches the batch size it flushes immediately; otherwise it relies on run() to flush on the configured interval. The queue is bounded, and the oldest record is dropped when the queue is full.

BatchConfig::default() reads:

  • OTEL_BLRP_SCHEDULE_DELAY
  • OTEL_BLRP_MAX_QUEUE_SIZE
  • OTEL_BLRP_MAX_EXPORT_BATCH_SIZE
  • OTEL_BLRP_EXPORT_TIMEOUT

#Trace-aware logging

If emit() receives a context with a valid active span, the emitted log record stores a local SpanContext so exporters can correlate logs with traces.

AnyValue

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pub(all) enum AnyValue {
  Bool(Bool)
  Int64(Int64)
  Double(Double)
  String(String)
  Bytes(Bytes)
  Array(Array[AnyValue])
  Map(Array[KeyValue])
} derive(Eq, ToJson, 
Debug)

Structured log value preserved by the SDK and OTLP exporter.

Use Map and Array when the backend should receive structured payloads rather than preformatted strings. Spec: https://opentelemetry.io/docs/specs/otel/common/#anyvalue

AnyValue::from_common

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Converts a shared SDK attribute value into a log-specific structured value. Spec: https://opentelemetry.io/docs/specs/otel/common/#anyvalue

BatchConfig

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pub struct BatchConfig {
  max_queue_size : Int
  max_export_batch_size : Int
  scheduled_delay_millis : Int
  export_timeout_millis : Int
} derive(Compare, Eq, Hash, ToJson, 
Debug)

Configuration for batch log processing. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#batching-processor

BatchConfig::new

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fn BatchConfig::new(max_queue_size? : Int, max_export_batch_size? : Int, scheduled_delay_millis? : Int, export_timeout_millis? : Int) -> BatchConfig

Creates normalized batch log processor configuration. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#batching-processor

BatchLogProcessor

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pub struct BatchLogProcessor {
  inner : LogProcessor
  state : 
Ref[BatchProcessorState]
}

Processor that buffers log records and exports them in batches.

The background loop is not started automatically. Use global/facade spawn_background_tasks() after provider registration. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#batching-processor

BatchLogProcessor::into_log_processor

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fn BatchLogProcessor::into_log_processor(self : BatchLogProcessor) -> LogProcessor

Erases the concrete batch processor type into LogProcessor. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#batching-processor

BatchLogProcessor::new

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Creates a batch log processor with a bounded queue. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#batching-processor

BatchLogProcessor::run

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async fn BatchLogProcessor::run(self : BatchLogProcessor) -> Unit

Background loop for scheduled batch exports. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#batching-processor

BatchProcessorState

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type BatchProcessorState

InMemoryLogExporter

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pub struct InMemoryLogExporter {
  state : 
Ref[InMemoryLogExporterState]
}

Test exporter that keeps finished logs in memory. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordexporter

InMemoryLogExporter::finished_logs

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Returns the finished log records accumulated so far. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordexporter

InMemoryLogExporter::into_log_exporter

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fn InMemoryLogExporter::into_log_exporter(self : InMemoryLogExporter) -> LogExporter

Erases the concrete in-memory exporter type into LogExporter. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#export

InMemoryLogExporter::new

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Creates an empty in-memory log exporter. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordexporter

InMemoryLogExporter::reset

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fn InMemoryLogExporter::reset(self : InMemoryLogExporter) -> Unit

Clears the in-memory log buffer. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordexporter

InMemoryLogExporterState

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type InMemoryLogExporterState

KeyValue

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Structured log attribute key/value pair. Spec: https://opentelemetry.io/docs/specs/otel/logs/data-model/#field-attributes

KeyValue::from_common

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Converts a shared SDK attribute into a log-specific structured attribute. Spec: https://opentelemetry.io/docs/specs/otel/logs/data-model/#field-attributes

KeyValue::new

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fn KeyValue::new(key : StringView, value : AnyValue) -> KeyValue

Creates a structured log attribute. Spec: https://opentelemetry.io/docs/specs/otel/logs/data-model/#field-attributes

LogExporter

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pub struct LogExporter {
  export_fn : async (ArrayView[LogRecord]) -> Result[Unit, 
OTelSdkError]
  force_flush_fn : async () -> Result[Unit, 
OTelSdkError]
  shutdown_fn : async () -> Result[Unit, 
OTelSdkError]
  name_fn : () -> String
}

Exporter callback wrapper for log batches. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordexporter

LogExporter::export_batch

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Exports one batch of log records. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#export

LogExporter::force_flush

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Requests exporter flush. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#forceflush

LogExporter::name

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fn LogExporter::name(self : LogExporter) -> String

Returns a human-readable exporter name. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordexporter

LogExporter::new

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fn LogExporter::new(export_fn : async (ArrayView[LogRecord]) -> Result[Unit, 
OTelSdkError], force_flush_fn? : async () -> Result[Unit, 
OTelSdkError], shutdown_fn? : async () -> Result[Unit, 
OTelSdkError], name_fn? : () -> String) -> LogExporter

Builds a log exporter from callbacks. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordexporter

LogExporter::shutdown

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Requests exporter shutdown. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#shutdown

LogExporter::shutdown_with_timeout

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async fn LogExporter::shutdown_with_timeout(self : LogExporter, timeout_millis : Int) -> Result[Unit, 
OTelSdkError]

Requests exporter shutdown with an optional timeout budget in milliseconds. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#shutdown

LogProcessor

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pub struct LogProcessor {
  emit_fn : async (LogRecord) -> Unit
  force_flush_fn : async () -> Result[Unit, 
OTelSdkError]
  shutdown_fn : async () -> Result[Unit, 
OTelSdkError]
}

Processing hook interface for logs.

Processors receive immutable log snapshots after the logger attaches resource and instrumentation scope metadata. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordprocessor

LogProcessor::emit

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async fn LogProcessor::emit(self : LogProcessor, record : LogRecord) -> Unit

Processes one log record. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordprocessor

LogProcessor::force_flush

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Requests processor flush. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordprocessor

LogProcessor::new

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fn LogProcessor::new(emit_fn? : async (LogRecord) -> Unit, force_flush_fn? : async () -> Result[Unit, 
OTelSdkError], shutdown_fn? : async () -> Result[Unit, 
OTelSdkError]) -> LogProcessor

Builds a log processor from callbacks. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordprocessor

LogProcessor::shutdown

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Requests processor shutdown. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordprocessor

LogProcessor::shutdown_with_timeout

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async fn LogProcessor::shutdown_with_timeout(self : LogProcessor, timeout_millis : Int) -> Result[Unit, 
OTelSdkError]

Requests processor shutdown with an optional timeout budget in milliseconds. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logrecordprocessor

LogRecord

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pub struct LogRecord {
  event_name : String?
  target : String?
  body : AnyValue
  timestamp_unix_nano : Int64
  observed_timestamp_unix_nano : Int64
  severity_number : SeverityNumber?
  severity_text : String?
  attributes : Array[KeyValue]
  trace_context : 
SpanContext?
  resource : 
Resource
  instrumentation_scope : 
InstrumentationScope
} derive(Eq, ToJson, 
Debug)

Immutable log payload exported by processors and exporters. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#additional-logrecord-interfaces

LogRecord::new

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fn LogRecord::new(body : AnyValue, timestamp_unix_nano? : Int64, observed_timestamp_unix_nano? : Int64, severity_number? : SeverityNumber?, severity_text? : String?, event_name? : String?, target? : String?, attributes? : ArrayView[KeyValue], trace_context? : 
SpanContext?, resource? : 
Resource, instrumentation_scope? : 
InstrumentationScope) -> LogRecord

Creates a log record snapshot.

This is the immutable SDK-side representation. Public API users usually build interface/logs.LogRecord values and let Logger::emit() convert them into this type. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#additional-logrecord-interfaces

LoggerProviderState

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type LoggerProviderState

SdkLogger

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Logger scoped to one instrumentation library.

The instrumentation scope is copied onto every emitted log record. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logger

SdkLogger::emit

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async fn SdkLogger::emit(self : SdkLogger, body : AnyValue, context? : 
Context, severity_number? : SeverityNumber?, severity_text? : String?, event_name? : String?, target? : String?, attributes? : ArrayView[KeyValue], timestamp_unix_nano? : Int64, observed_timestamp_unix_nano? : Int64) -> Unit

Emits one log record through the provider pipeline.

The logger attaches resource and instrumentation scope metadata before forwarding the record to processors. Spec: https://opentelemetry.io/docs/specs/otel/logs/api/#emit-a-logrecord

SdkLoggerProvider

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pub struct SdkLoggerProvider {
  state : 
Ref[LoggerProviderState]
}

Owns resource metadata and the processor pipeline for loggers.

Applications create one provider, configure processors/exporters, register it if needed, then shut it down during application teardown. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProvider::builder

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Starts building a logger provider with the default resource.

Add processors or exporters before calling build(). A provider with no processors accepts logs but exports nothing. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProvider::force_flush

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Flushes every configured processor. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#forceflush

SdkLoggerProvider::into_logger_provider

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Erases this SDK provider into the public logs API provider. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProvider::logger

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fn SdkLoggerProvider::logger(self : SdkLoggerProvider, name : StringView, version? : String?, schema_url? : String?, attributes? : ArrayView[
KeyValue]) -> SdkLogger

Creates a logger scoped to the supplied instrumentation library metadata. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#logger-creation

SdkLoggerProvider::resource

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Returns the provider resource. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProvider::shutdown

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Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#shutdown

SdkLoggerProvider::shutdown_with_timeout

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async fn SdkLoggerProvider::shutdown_with_timeout(self : SdkLoggerProvider, timeout_millis : Int) -> Result[Unit, 
OTelSdkError]

Shuts down every configured processor and marks the provider unusable. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#shutdown

SdkLoggerProvider::spawn_batch_processor_tasks

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fn SdkLoggerProvider::spawn_batch_processor_tasks(self : SdkLoggerProvider, group : 
TaskGroup[Unit], allow_failure? : Bool) -> Unit

Spawns background tasks for all configured batch processors. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProviderBuilder

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pub struct SdkLoggerProviderBuilder {
  resource : 
Resource
  processors : Array[LogProcessor]
  batch_processors : Array[BatchLogProcessor]
}

Builder for SdkLoggerProvider. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProviderBuilder::build

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Builds the logger provider. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProviderBuilder::with_batch_exporter

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Appends a batch processor around the exporter and registers it for background execution.

The processor is registered with the provider, but its export loop only runs after spawn_batch_processor_tasks() or the facade/global equivalent is called. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProviderBuilder::with_log_processor

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Appends a processor to the logger pipeline. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProviderBuilder::with_resource

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Replaces the provider resource. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SdkLoggerProviderBuilder::with_simple_exporter

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Appends a simple processor around the exporter.

Each emitted log is exported from SdkLogger::emit(). Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#loggerprovider

SeverityNumber

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pub(all) enum SeverityNumber {
  Trace
  Trace2
  Trace3
  Trace4
  Debug
  Debug2
  Debug3
  Debug4
  Info
  Info2
  Info3
  Info4
  Warn
  Warn2
  Warn3
  Warn4
  Error
  Error2
  Error3
  Error4
  Fatal
  Fatal2
  Fatal3
  Fatal4
} derive(Compare, Eq, Hash, ToJson, 
Debug)

Full OpenTelemetry severity ladder used by LogRecord.

The 24 slots let bridges preserve finer-grained severity from existing logging frameworks. Spec: https://opentelemetry.io/docs/specs/otel/logs/data-model/#field-severitynumber

SimpleLogProcessor

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pub struct SimpleLogProcessor {
  inner : LogProcessor
}

Processor that exports each log record immediately.

Useful for tests and local debugging. Network exporters should usually be wrapped by BatchLogProcessor. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#simple-processor

SimpleLogProcessor::into_log_processor

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fn SimpleLogProcessor::into_log_processor(self : SimpleLogProcessor) -> LogProcessor

Erases the concrete simple processor type into LogProcessor. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#simple-processor

SimpleLogProcessor::new

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Creates a simple processor that exports each emitted record immediately. Spec: https://opentelemetry.io/docs/specs/otel/logs/sdk/#simple-processor

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