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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

    source
    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

    source

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

    BatchConfig

    source
    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

    source
    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

    source
    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

    source
    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

    source

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

    BatchLogProcessor::run

    source
    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

    source
    type BatchProcessorState

    InMemoryLogExporter

    source
    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

    source

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

    InMemoryLogExporter::into_log_exporter

    source
    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

    source

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

    InMemoryLogExporter::reset

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

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

    InMemoryLogExporterState

    source
    type InMemoryLogExporterState

    KeyValue

    source

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

    KeyValue::from_common

    source

    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

    source
    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

    source
    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

    source

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

    LogExporter::force_flush

    source

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

    LogExporter::name

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

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

    LogExporter::new

    source
    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

    source

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

    LogExporter::shutdown_with_timeout

    source
    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

    source
    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

    source
    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

    source

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

    LogProcessor::new

    source
    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

    source

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

    LogProcessor::shutdown_with_timeout

    source
    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

    source
    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

    source
    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

    source
    type LoggerProviderState

    SdkLogger

    source

    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

    source
    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

    source
    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

    source

    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

    source

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

    SdkLoggerProvider::into_logger_provider

    source

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

    SdkLoggerProvider::logger

    source
    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

    source

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

    SdkLoggerProvider::shutdown

    source

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

    SdkLoggerProvider::shutdown_with_timeout

    source
    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

    source
    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

    source
    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

    source

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

    SdkLoggerProviderBuilder::with_batch_exporter

    source

    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

    source

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

    SdkLoggerProviderBuilder::with_resource

    source

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

    SdkLoggerProviderBuilder::with_simple_exporter

    source

    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

    source
    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

    source
    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

    source
    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

    source

    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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