feat: finalize logger

README.md

@@ -8,12 +8,13 @@ This repository is the Dart implementation of the [OpenTelemetry project](https:
 | - | - |
 | Traces | Beta |
 | Metrics | Alpha |
-| Logs | Unimplemented |
+| Logs | Beta |
 
 ## Getting Started
 
 This section will show you how to initialize the OpenTelemetry SDK, capture a span, and propagate context.
 
+### Tacers
 ### Initialize the OpenTelemetry SDK
 
 ```dart
@@ -62,6 +63,45 @@ void main(List<String> args) {
 }
 ```
 
+### Logs
+#### Initialize the OpenTelemetry SDK
+
+```dart
+import 'package:opentelemetry/sdk.dart'
+    show
+    BatchLogRecordProcessor,
+        OTLPLogExporter,
+        ConsoleExporter,
+        SimpleLogRecordProcessor,
+        TracerProviderBase;
+import 'package:opentelemetry/api.dart'
+    show registerGlobalLogProvider, globalLogProvider;
+
+void main(List<String> args) {
+  final logProvider = TracerProviderBase(processors: [
+    BatchLogRecordProcessor(
+        OTLPLogExporter(Uri.parse('https://my-collector.com/v1/traces'))),
+    SimpleLogRecordProcessor(ConsoleLogRecordExporter())
+  ]);
+
+  registerGlobalLogProvider(logProvider);
+  final tracer = globalLogProvider.get('logger-name');
+}
+```
+
+### Capture a Log 
+```dart
+import 'package:opentelemetry/api.dart' show StatusCode, globalLogProvider;
+
+void main(List<String> args) {
+  final logger = globalLogProvider.get('logger-name');
+
+  logger.emit(body: "Hello World!");
+}
+```
+
+
+
 ### Propagate Context
 
 ### Intra-process

lib/api.dart

@@ -5,22 +5,21 @@ export 'src/api/common/attribute.dart' show Attribute;
 export 'src/api/common/resource_attributes.dart' show ResourceAttributes;
 export 'src/api/common/semantic_attributes.dart' show SemanticAttributes;
 export 'src/api/context/context.dart'
-    show
-        Context,
-        ContextKey,
-        contextWithSpan,
-        contextWithSpanContext,
-        spanContextFromContext,
-        spanFromContext,
-        zone;
-export 'src/api/context/context_manager.dart'
-    show globalContextManager, registerGlobalContextManager;
+    show Context, ContextKey, contextWithSpan, contextWithSpanContext, spanContextFromContext, spanFromContext, zone;
+export 'src/api/context/context_manager.dart' show globalContextManager, registerGlobalContextManager;
 export 'src/api/exporters/span_exporter.dart' show SpanExporter;
 export 'src/api/instrumentation_library.dart' show InstrumentationLibrary;
+export 'src/api/logs/log_record.dart' show Severity;
+export 'src/api/logs/logger.dart' show Logger;
+export 'src/api/logs/logger_provider.dart' show LoggerProvider;
+export 'src/api/logs/noop/noop_logger.dart' show NoopLogger;
+export 'src/api/logs/noop/noop_logger_provider.dart' show NoopLoggerProvider;
 export 'src/api/open_telemetry.dart'
     show
+        globalLogProvider,
         globalTextMapPropagator,
         globalTracerProvider,
+        registerGlobalLogProvider,
         registerGlobalTextMapPropagator,
         registerGlobalTracerProvider,
         trace,
@@ -30,8 +29,7 @@ export 'src/api/open_telemetry.dart'
 export 'src/api/propagation/extractors/text_map_getter.dart' show TextMapGetter;
 export 'src/api/propagation/injectors/text_map_setter.dart' show TextMapSetter;
 export 'src/api/propagation/text_map_propagator.dart' show TextMapPropagator;
-export 'src/api/propagation/w3c_trace_context_propagator.dart'
-    show W3CTraceContextPropagator;
+export 'src/api/propagation/w3c_trace_context_propagator.dart' show W3CTraceContextPropagator;
 export 'src/api/span_processors/span_processor.dart' show SpanProcessor;
 export 'src/api/trace/id_generator.dart' show IdGenerator;
 export 'src/api/trace/span.dart' show Span, SpanKind;

lib/sdk.dart

@@ -1,30 +1,37 @@
 // Copyright 2021-2022 Workiva.
 // Licensed under the Apache License, Version 2.0. Please see https://github.com/Workiva/opentelemetry-dart/blob/master/LICENSE for more information
 
-export 'src/sdk/instrumentation_library.dart' show InstrumentationLibrary;
 export 'src/sdk/common/attributes.dart' show Attributes;
 export 'src/sdk/common/instrumentation_scope.dart' show InstrumentationScope;
+export 'src/sdk/instrumentation_library.dart' show InstrumentationLibrary;
+export 'src/sdk/logs/export_result.dart' show ExportResult, ExportResultCode;
+export 'src/sdk/logs/exporters/console_log_record_exporter.dart' show ConsoleLogRecordExporter;
+export 'src/sdk/logs/exporters/inmemory_log_record_exporter.dart' show InMemoryLogRecordExporter;
+export 'src/sdk/logs/exporters/log_record_exporter.dart' show LogRecordExporter;
+export 'src/sdk/logs/exporters/otlp_log_exporter.dart' show OTLPLogExporter;
+export 'src/sdk/logs/log_record.dart' show ReadableLogRecord, ReadWriteLogRecord, LogRecord;
+export 'src/sdk/logs/log_record_limit.dart' show LogRecordLimits;
+export 'src/sdk/logs/logger.dart' show Logger;
+export 'src/sdk/logs/logger_provider.dart' show LoggerProvider;
+export 'src/sdk/logs/processors/batch_log_record_processor.dart' show BatchLogRecordProcessor;
+export 'src/sdk/logs/processors/log_record_processor.dart' show LogRecordProcessor;
+export 'src/sdk/logs/processors/simple_log_record_processor.dart' show SimpleLogRecordProcessor;
 export 'src/sdk/resource/resource.dart' show Resource;
-export 'src/sdk/time_providers/datetime_time_provider.dart'
-    show DateTimeTimeProvider;
+export 'src/sdk/time_providers/datetime_time_provider.dart' show DateTimeTimeProvider;
 export 'src/sdk/time_providers/time_provider.dart' show TimeProvider;
-export 'src/sdk/trace/exporters/span_exporter.dart' show SpanExporter;
 export 'src/sdk/trace/exporters/collector_exporter.dart' show CollectorExporter;
 export 'src/sdk/trace/exporters/console_exporter.dart' show ConsoleExporter;
+export 'src/sdk/trace/exporters/span_exporter.dart' show SpanExporter;
 export 'src/sdk/trace/id_generator.dart' show IdGenerator;
+export 'src/sdk/trace/read_only_span.dart' show ReadOnlySpan;
+export 'src/sdk/trace/read_write_span.dart' show ReadWriteSpan;
 export 'src/sdk/trace/sampling/always_off_sampler.dart' show AlwaysOffSampler;
 export 'src/sdk/trace/sampling/always_on_sampler.dart' show AlwaysOnSampler;
-export 'src/sdk/trace/sampling/parent_based_sampler.dart'
-    show ParentBasedSampler;
+export 'src/sdk/trace/sampling/parent_based_sampler.dart' show ParentBasedSampler;
 export 'src/sdk/trace/sampling/sampler.dart' show Sampler;
-export 'src/sdk/trace/sampling/sampling_result.dart'
-    show Decision, SamplingResult;
-export 'src/sdk/trace/read_only_span.dart' show ReadOnlySpan;
-export 'src/sdk/trace/read_write_span.dart' show ReadWriteSpan;
+export 'src/sdk/trace/sampling/sampling_result.dart' show Decision, SamplingResult;
 export 'src/sdk/trace/span_limits.dart' show SpanLimits;
+export 'src/sdk/trace/span_processors/batch_processor.dart' show BatchSpanProcessor;
+export 'src/sdk/trace/span_processors/simple_processor.dart' show SimpleSpanProcessor;
 export 'src/sdk/trace/span_processors/span_processor.dart' show SpanProcessor;
-export 'src/sdk/trace/span_processors/batch_processor.dart'
-    show BatchSpanProcessor;
-export 'src/sdk/trace/span_processors/simple_processor.dart'
-    show SimpleSpanProcessor;
 export 'src/sdk/trace/tracer_provider.dart' show TracerProviderBase;

lib/src/api/context/context.dart

@@ -7,7 +7,7 @@ import 'package:collection/collection.dart';
 import 'package:logging/logging.dart';
 import 'package:meta/meta.dart';
 
-import '../../../api.dart';
+import '../../../api.dart' hide Logger;
 import '../trace/nonrecording_span.dart' show NonRecordingSpan;
 
 final Logger _log = Logger('opentelemetry');

lib/src/api/logs/logger.dart

@@ -2,12 +2,11 @@
 // Licensed under the Apache License, Version 2.0. Please see https://github.com/Workiva/opentelemetry-dart/blob/master/LICENSE for more information
 
 import '../../../api.dart' as api;
-import '../../../sdk.dart' as sdk;
 import 'log_record.dart';
 
 abstract class Logger {
   void emit({
-    sdk.Attributes? attributes,
+    List<api.Attribute> attributes = const <api.Attribute>[],
     api.Context? context,
     dynamic body,
     DateTime? observedTimestamp,

lib/src/api/logs/logger_provider.dart

@@ -7,7 +7,7 @@ import 'package:opentelemetry/src/api/logs/logger.dart';
 abstract class LoggerProvider {
   /// Gets or creates a [Logger] instance.
   ///
-  /// The meter is identified by the combination of [name], [version],
+  /// The logger is identified by the combination of [name], [version],
   /// [schemaUrl] and [attributes]. The [name] SHOULD uniquely identify the
   /// instrumentation scope, such as the instrumentation library
   /// (e.g. io.opentelemetry.contrib.mongodb), package, module or class name.

lib/src/api/logs/noop/noop_logger.dart

@@ -1,17 +1,17 @@
 // Copyright 2021-2022 Workiva.
 // Licensed under the Apache License, Version 2.0. Please see https://github.com/Workiva/opentelemetry-dart/blob/master/LICENSE for more information
 
+import 'package:opentelemetry/src/api/common/attribute.dart';
 import 'package:opentelemetry/src/api/context/context.dart';
 import 'package:opentelemetry/src/api/logs/log_record.dart';
 import 'package:opentelemetry/src/api/logs/logger.dart';
-import 'package:opentelemetry/src/sdk/common/attributes.dart';
 
 class NoopLogger implements Logger {
   const NoopLogger();
 
   @override
   void emit({
-    Attributes? attributes,
+    List<Attribute> attributes = const <Attribute>[],
     Context? context,
     dynamic body,
     DateTime? observedTimestamp,

lib/src/api/open_telemetry.dart

@@ -7,20 +7,19 @@ import 'package:meta/meta.dart';
 
 import '../../api.dart' as api;
 import '../../src/sdk/trace/tracer.dart' as sdk show Tracer;
-import '../experimental_api.dart';
 import 'propagation/noop_text_map_propagator.dart';
 import 'trace/noop_tracer_provider.dart';
 
 final api.TracerProvider _noopTracerProvider = NoopTracerProvider();
 final api.TextMapPropagator _noopTextMapPropagator = NoopTextMapPropagator();
-final LoggerProvider _noopLoggerProvider = NoopLoggerProvider();
-LoggerProvider _logProvider = _noopLoggerProvider;
+final api.LoggerProvider _noopLoggerProvider = api.NoopLoggerProvider();
+api.LoggerProvider _logProvider = _noopLoggerProvider;
 api.TracerProvider _tracerProvider = _noopTracerProvider;
 api.TextMapPropagator _textMapPropagator = _noopTextMapPropagator;
 
 api.TracerProvider get globalTracerProvider => _tracerProvider;
 
-LoggerProvider get globalLogProvider => _logProvider;
+api.LoggerProvider get globalLogProvider => _logProvider;
 
 api.TextMapPropagator get globalTextMapPropagator => _textMapPropagator;
 
@@ -34,7 +33,7 @@ void registerGlobalTracerProvider(api.TracerProvider tracerProvider) {
   _tracerProvider = tracerProvider;
 }
 
-void registerGlobalLogProvider(LoggerProvider logProvider) {
+void registerGlobalLogProvider(api.LoggerProvider logProvider) {
   if (_logProvider != _noopLoggerProvider) {
     throw StateError('A global LoggerProvider has already been created. '
         'registerGlobalLoggerProvider must be called only once before any '

lib/src/experimental_api.dart

@@ -11,12 +11,7 @@ export 'api/context/noop_context_manager.dart' show NoopContextManager;
 export 'api/context/zone_context.dart' show ZoneContext;
 export 'api/context/zone_context_manager.dart' show ZoneContextManager;
 export 'api/metrics/counter.dart' show Counter;
-export 'api/metrics/meter_provider.dart' show MeterProvider;
 export 'api/metrics/meter.dart' show Meter;
+export 'api/metrics/meter_provider.dart' show MeterProvider;
 export 'api/metrics/noop/noop_meter.dart' show NoopMeter;
 export 'api/trace/nonrecording_span.dart' show NonRecordingSpan;
-export 'api/logs/logger.dart' show Logger;
-export 'api/logs/log_record.dart' show Severity;
-export 'api/logs/logger_provider.dart' show LoggerProvider;
-export 'api/logs/noop/noop_logger.dart' show NoopLogger;
-export 'api/logs/noop/noop_logger_provider.dart' show NoopLoggerProvider;

lib/src/experimental_sdk.dart

@@ -7,6 +7,6 @@ library experimental_sdk;
 import 'package:meta/meta.dart';
 
 export 'sdk/metrics/counter.dart' show Counter;
-export 'sdk/metrics/meter_provider.dart' show MeterProvider;
 export 'sdk/metrics/meter.dart' show Meter;
+export 'sdk/metrics/meter_provider.dart' show MeterProvider;
 export 'sdk/resource/resource.dart' show Resource;

lib/src/sdk/common/limits.dart

@@ -7,8 +7,7 @@ import '../../../sdk.dart' as sdk;
 
 /// Applies given [sdk.SpanLimits] to a list of [api.SpanLink]s.
 @protected
-List<api.SpanLink> applyLinkLimits(
-    List<api.SpanLink> links, sdk.SpanLimits limits) {
+List<api.SpanLink> applyLinkLimits(List<api.SpanLink> links, sdk.SpanLimits limits) {
   final spanLink = <api.SpanLink>[];
 
   for (final link in links) {
@@ -27,8 +26,7 @@ List<api.SpanLink> applyLinkLimits(
     for (final attr in link.attributes) {
       // if attributes num is already greater than maxNumAttributesPerLink
       // and this key doesn't exist in the list, drop it.
-      if (attributeMap.length >= limits.maxNumAttributesPerLink &&
-          !attributeMap.containsKey(attr.key)) {
+      if (attributeMap.length >= limits.maxNumAttributesPerLink && !attributeMap.containsKey(attr.key)) {
         droppedAttributes++;
         continue;
       }
@@ -49,8 +47,7 @@ List<api.SpanLink> applyLinkLimits(
       }
     }
 
-    spanLink.add(api.SpanLink(link.context,
-        attributes: linkAttributes, droppedAttributes: droppedAttributes));
+    spanLink.add(api.SpanLink(link.context, attributes: linkAttributes, droppedAttributes: droppedAttributes));
   }
   return spanLink;
 }
@@ -63,20 +60,46 @@ api.Attribute applyAttributeLimits(api.Attribute attr, sdk.SpanLimits limits) {
 
   if (attr.value is String) {
     attr = api.Attribute.fromString(
-        attr.key,
-        applyAttributeLengthLimit(
-            attr.value as String, limits.maxNumAttributeLength));
+        attr.key, applyAttributeLengthLimit(attr.value as String, limits.maxNumAttributeLength));
   } else if (attr.value is List<String>) {
     final listString = attr.value as List<String>;
     for (var j = 0; j < listString.length; j++) {
-      listString[j] = applyAttributeLengthLimit(
-          listString[j], limits.maxNumAttributeLength);
+      listString[j] = applyAttributeLengthLimit(listString[j], limits.maxNumAttributeLength);
     }
     attr = api.Attribute.fromStringList(attr.key, listString);
   }
   return attr;
 }
 
+@protected
+api.Attribute applyAttributeLimitsForLog(
+  api.Attribute attr,
+  sdk.LogRecordLimits limits,
+) {
+  // if maxNumAttributeLength is less than zero, then it has unlimited length.
+  if (limits.attributeValueLengthLimit < 0) return attr;
+
+  if (attr.value is String) {
+    return (attr.value as String).length > limits.attributeValueLengthLimit
+        ? api.Attribute.fromString(attr.key, (attr.value as String).substring(0, limits.attributeValueLengthLimit))
+        : attr;
+  } else if (attr.value is List<String>) {
+    final list = (attr.value as List<String>);
+    List<String>? truncated;
+    for (int i = 0; i < list.length; i++) {
+      final s = list[i];
+      if (s.length > limits.attributeValueLengthLimit) {
+        truncated ??= List<String>.from(list, growable: false);
+        truncated[i] = s.substring(0, limits.attributeValueLengthLimit);
+      }
+    }
+    if (truncated != null) {
+      return api.Attribute.fromStringList(attr.key, truncated);
+    }
+  }
+  return attr;
+}
+
 /// Truncate just strings which length is longer than configuration.
 /// Reference: https://github.com/open-telemetry/opentelemetry-java/blob/14ffacd1cdd22f5aa556eeda4a569c7f144eadf2/sdk/common/src/main/java/io/opentelemetry/sdk/internal/AttributeUtil.java#L80
 @protected

lib/src/sdk/logs/export_result.dart

@@ -0,0 +1,15 @@
+// Copyright 2021-2022 Workiva.
+// Licensed under the Apache License, Version 2.0. Please see https://github.com/Workiva/opentelemetry-dart/blob/master/LICENSE for more information
+
+class ExportResult {
+  final ExportResultCode code;
+  final Exception? error;
+  final StackTrace? stackTrace;
+
+  ExportResult({required this.code, this.error, this.stackTrace});
+}
+
+enum ExportResultCode {
+  success,
+  failed,
+}