dartastic_opentelemetry_api 1.0.0-beta

Dartastic.io's OpenTelemetry API for Dart following the OpenTelemetry specification. Supports all platforms including web.

example/dartastic_opentelemetry_api_example.dart

// Licensed under the Apache License, Version 2.0
// Copyright 2025, Michael Bushe, All rights reserved.

import 'package:dartastic_opentelemetry_api/dartastic_opentelemetry_api.dart';

/// The API does nothing on its own; it's more typical to use the SDK.
/// However, as required by the OpenTelemetry Specification, the API
/// works (as a no-op) without the SDK installed.
void main() {
  OTelAPI.initialize(endpoint: 'http://localhost:4317');
  final stringAttribute = OTelAPI.attributeString('example_string_key', 'foo');
  final boolAttribute = OTelAPI.attributeBool('example_bool_key', true);
  final intAttr = OTelAPI.attributeInt('example_int_key', 42);
  final doubleAttribute = OTelAPI.attributeDouble('example_double_key', 42.1);
  final stringListAttribute = OTelAPI.attributeStringList(
      'example_string_list_key', ['foo', 'bar', 'baz']);
  final boolListAttribute =
      OTelAPI.attributeBoolList('example_bool_key', [true, false, true]);
  final intListAttr =
      OTelAPI.attributeIntList('example_int_list_key', [42, 43, 44]);
  final doubleListAttribute = OTelAPI.attributeDoubleList(
      'example_double_list_key', [42.0, 42.1, 42.2]);

  OTelAPI.attributes([
    stringAttribute,
    boolAttribute,
    intAttr,
    doubleAttribute,
    stringListAttribute,
    boolListAttribute,
    intListAttr,
    doubleListAttribute
  ]);

  final baggage = OTelAPI.baggageForMap({'userId': 'yoda'});
  // Create a context with the baggage and run the example within it.
  // This ensures correct propagation across asynchronous boundaries.
  OTelAPI.context(baggage: baggage).runSync(() {
    //Trace Signal
    final defaultGlobalAPINOOPTracerProvider = OTelAPI.tracerProvider();
    final tracer = defaultGlobalAPINOOPTracerProvider
        .getTracer('dart-otel-api-example-service');

    // Use withSpan to make the span active within its scope
    final span = tracer.startSpan('doSomeExampleSpan');
    tracer.withSpan(span, () {
      // Same thing as above, more simply but will some loss of type checking
      // If your Map has anything but the types above and exception will be thrown.
      final equalToTheAbove = OTelAPI.attributesFromMap({
        'example_string_key': 'foo',
        'example_bool_key': true,
        'example_int_key': 42,
        'example_double_key': 42.1,
        'example_string_list_key': ['foo', 'bar', 'baz'],
        'example_bool_list_key': [true, false, true],
        'example_int_list_key': [42, 43, 44],
        'example_double_list_key': [42.0, 42.1, 42.2]
      });
      span.attributes = equalToTheAbove;
      span.addEventNow('data-retrieved',
          OTelAPI.attributes([OTelAPI.attributeString('event-foo', 'bar')]));
      span.end(
          spanStatus:
              SpanStatusCode.Ok); //Capitalized Ok to match the OTel spec
    });

    //Log Signal
    final defaultGlobalAPINOOPLoggerProvider = OTelAPI.loggerProvider();
    final logger = defaultGlobalAPINOOPLoggerProvider
        .getLogger('dart-otel-api-example-service');

    logger.emit(eventName: 'heartbeat', body: 'Service is healthy.');

    logger.emit(
      eventName: 'user_login',
      severityNumber: Severity.INFO,
      body: 'User successfully logged in.',
      attributes: Attributes.of({
        'user.id': 42,
        'auth.method': 'password',
      }),
    );

    logger.emit(
      eventName: 'cache_miss',
      severityText: 'WARN',
      body: 'Cache miss for requested key.',
      attributes: Attributes.of({
        'cache.key': 'profile_42',
        'cache.region': 'us-east-1',
      }),
    );

    final attrs = {
      'db.operation': 'update',
      'db.table': 'orders',
      'db.rows_affected': 3,
    }.toAttributes();

    logger.emit(
      eventName: 'order_update',
      severityNumber: Severity.INFO,
      body: 'Order update completed.',
      attributes: attrs,
    );

    logger.emit(
      eventName: 'batch_job_summary',
      severityNumber: Severity.INFO,
      body: [
        {'job': 'resize_images', 'status': 'ok'},
        {'job': 'generate_thumbnails', 'status': 'ok'},
        {'job': 'sync_metadata', 'status': 'failed'},
      ],
      attributes: Attributes.of({
        'batch.id': 'batch-2025-11-15-01',
        'jobs.total': 3,
      }),
    );

    logger.emit(
      eventName: 'payment_failure',
      severityText: 'ERROR',
      body: 'Payment could not be processed.',
      attributes: Attributes.of({
        'payment.user_id': 101,
        'payment.method': 'credit_card',
        'payment.gateway': 'stripe',
        'retry.count': 2,
      }),
    );
  });
}