Line data    Source code

       1              : // Copyright The OpenTelemetry Authors
       2              : // SPDX-License-Identifier: Apache-2.0
       3              : 
       4              : import 'package:dartastic_opentelemetry_api/dartastic_opentelemetry_api.dart';
       5              : 
       6              : import '../data/metric.dart';
       7              : import '../data/metric_point.dart';
       8              : import '../meter.dart';
       9              : import '../storage/sum_storage.dart';
      10              : import 'base_instrument.dart';
      11              : 
      12              : /// UpDownCounter is a synchronous instrument that records additive values.
      13              : ///
      14              : /// An UpDownCounter is used to measure a value that increases and decreases.
      15              : /// For example, the number of active requests, queue size, pool size.
      16              : class UpDownCounter<T extends num>
      17              :     implements APIUpDownCounter<T>, SDKInstrument {
      18              :   /// The underlying API UpDownCounter.
      19              :   final APIUpDownCounter<T> _apiCounter;
      20              : 
      21              :   /// The Meter that created this UpDownCounter.
      22              :   final Meter _meter;
      23              : 
      24              :   /// Storage for accumulating up-down counter measurements.
      25              :   final SumStorage<T> _storage;
      26              : 
      27              :   /// Creates a new UpDownCounter instance.
      28            5 :   UpDownCounter({required APIUpDownCounter<T> apiCounter, required Meter meter})
      29              :       : _apiCounter = apiCounter,
      30              :         _meter = meter,
      31            5 :         _storage = SumStorage<T>(
      32              :           isMonotonic: false,
      33           10 :           exemplarFilter: meter.provider.exemplarFilter,
      34              :         ) {
      35              :     // Register this instrument with the meter provider
      36           25 :     _meter.provider.registerInstrument(_meter.name, this);
      37              :   }
      38              : 
      39            5 :   @override
      40           10 :   String get name => _apiCounter.name;
      41              : 
      42            2 :   @override
      43            4 :   String? get unit => _apiCounter.unit;
      44              : 
      45            2 :   @override
      46            4 :   String? get description => _apiCounter.description;
      47              : 
      48            1 :   @override
      49            2 :   bool isEnabled() => _meter.isEnabled();
      50              : 
      51            5 :   @override
      52            5 :   APIMeter get meter => _meter;
      53              : 
      54            1 :   @override
      55              :   bool get isCounter => false;
      56              : 
      57            1 :   @override
      58              :   bool get isUpDownCounter => true;
      59              : 
      60            1 :   @override
      61              :   bool get isGauge => false;
      62              : 
      63            1 :   @override
      64              :   bool get isHistogram => false;
      65              : 
      66            3 :   @override
      67              :   void add(T value, [Attributes? attributes]) {
      68              :     // First use the API implementation (no-op by default)
      69            6 :     _apiCounter.add(value, attributes);
      70              : 
      71              :     // In the SDK, we only check the meter's enabled state
      72            6 :     if (!_meter.isEnabled()) return;
      73              : 
      74              :     // Record the measurement in our storage
      75            9 :     _storage.record(value, attributes, Context.current);
      76              :   }
      77              : 
      78            1 :   @override
      79              :   void addWithMap(T value, Map<String, Object> attributeMap) {
      80              :     // Just convert to Attributes and call add
      81              :     final attributes =
      82            2 :         attributeMap.isEmpty ? null : attributeMap.toAttributes();
      83            1 :     add(value, attributes);
      84              :   }
      85              : 
      86              :   /// Gets the current value of the counter for a specific set of attributes.
      87              :   /// If no attributes are provided, returns the sum of all values across all attributes.
      88            3 :   T getValue([Attributes? attributes]) {
      89            6 :     return _storage.getValue(attributes);
      90              :   }
      91              : 
      92              :   /// Gets the current points for this counter.
      93              :   /// This is used by the SDK to collect metrics.
      94            1 :   List<MetricPoint<T>> collectPoints() {
      95            2 :     return _storage.collectPoints();
      96              :   }
      97              : 
      98            1 :   @override
      99              :   List<Metric> collectMetrics() {
     100            2 :     if (!isEnabled()) return [];
     101              : 
     102              :     // Get the points from storage
     103            1 :     final points = collectPoints();
     104              : 
     105            1 :     if (points.isEmpty) return [];
     106              : 
     107              :     // Create a metric with the collected points
     108            1 :     final metric = Metric(
     109            1 :       name: name,
     110            1 :       description: description,
     111            1 :       unit: unit,
     112              :       type: MetricType.sum, // UpDownCounter is still a sum, just not monotonic
     113              :       points: points,
     114              :     );
     115              : 
     116            1 :     return [metric];
     117              :   }
     118              : 
     119              :   /// Resets the counter. This is only used for Delta temporality.
     120            2 :   void reset() {
     121            4 :     _storage.reset();
     122              :   }
     123              : }