Metrics refactor (#432)

Examples/Stable Metric Sample/main.swift

@@ -69,7 +69,6 @@ basicConfiguration()
 
 // creating a new meter & instrument
 let meter = OpenTelemetry.instance.stableMeterProvider?.meterBuilder(name: "MyMeter").build()
-var gaugeBuilder = meter!.gaugeBuilder(name: "Gauge")
-var gauge = gaugeBuilder.buildWithCallback({ ObservableDoubleMeasurement in
+var gaugeBuilder = meter!.gaugeBuilder(name: "Gauge").buildWithCallback({ ObservableDoubleMeasurement in
   ObservableDoubleMeasurement.record(value: 1.0, attributes: ["test": AttributeValue.bool(true)])
 })

Sources/OpenTelemetryApi/Metrics/Stable/DefaultStableMeter.swift

@@ -0,0 +1,165 @@
+//
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+// 
+
+import Foundation
+
+
+public class DefaultStableMeter : StableMeter {
+
+  internal init() {}
+
+  public func counterBuilder(name: String) -> LongCounterBuilder {
+    NoopLongCounterBuilder()
+  }
+
+  public func upDownCounterBuilder(name: String) -> LongUpDownCounterBuilder {
+    NoopLongUpDownCounterBuilder()
+  }
+
+  public func histogramBuilder(name: String) -> DoubleHistogramBuilder {
+    NoopDoubleHistogramBuilder()
+  }
+
+  public func gaugeBuilder(name: String) -> DoubleGaugeBuilder {
+    NoopDoubleGaugeBuilder()
+  }
+
+  private class NoopLongUpDownCounterBuilder : LongUpDownCounterBuilder {
+    func ofDoubles() -> DoubleUpDownCounterBuilder {
+      NoopDoubleUpDownCounterBuilder()
+    }
+
+    func build() -> LongUpDownCounter {
+      NoopLongUpDownCounter()
+    }
+
+    func buildWithCallback(_ callback: @escaping (ObservableLongMeasurement) -> Void) -> ObservableLongUpDownCounter {
+      NoopObservableLongUpDownCounter()
+    }
+  }
+
+  private class NoopDoubleHistogramBuilder : DoubleHistogramBuilder {
+    func ofLongs() -> LongHistogramBuilder {
+      NoopLongHistogramBuilder()
+    }
+
+    func build() -> DoubleHistogram {
+      NoopDoubleHistogram()
+    }
+  }
+
+  private class NoopDoubleGaugeBuilder : DoubleGaugeBuilder {
+    func ofLongs() -> LongGaugeBuilder {
+      NoopLongGaugeBuilder()
+    }
+
+    func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement) -> Void) -> ObservableDoubleGauge {
+      NoopObservableDoubleGauge()
+    }
+  }
+
+  private class NoopLongGaugeBuilder : LongGaugeBuilder {
+    func buildWithCallback(_ callback: @escaping (ObservableLongMeasurement) -> Void) -> ObservableLongGauge {
+        NoopObservableLongGauge()
+    }
+  }
+
+  private struct NoopObservableLongGauge : ObservableLongGauge {}
+
+  private struct NoopObservableDoubleGauge : ObservableDoubleGauge {}
+
+  private class NoopDoubleUpDownCounterBuilder : DoubleUpDownCounterBuilder {
+    func build() -> DoubleUpDownCounter {
+      NoopDoubleUpDownCounter()
+    }
+
+    func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement) -> Void) -> ObservableDoubleUpDownCounter {
+      NoopObservableDoubleUpDownCounter()
+    }
+  }
+
+  private struct NoopObservableDoubleUpDownCounter : ObservableDoubleUpDownCounter {}
+
+  private struct NoopDoubleUpDownCounter : DoubleUpDownCounter {
+    mutating func add(value: Double) {}
+    mutating func add(value: Double, attributes: [String : AttributeValue]) {}
+  }
+
+  private class NoopLongUpDownCounter : LongUpDownCounter {
+    func add(value: Int) {}
+    func add(value: Int, attributes: [String : AttributeValue]) {}
+  }
+
+  private class NoopLongHistogramBuilder : LongHistogramBuilder {
+    func build() -> LongHistogram {
+      NoopLongHistogram()
+    }
+  }
+
+  private struct NoopLongHistogram : LongHistogram {
+    mutating func record(value: Int) {}
+    mutating func record(value: Int, attributes: [String : AttributeValue]) {}
+  }
+
+  private class NoopObservableLongUpDownCounter : ObservableLongUpDownCounter {}
+
+  private class NoopDoubleHistogram : DoubleHistogram {
+    func record(value: Double) {}
+    func record(value: Double, attributes: [String : AttributeValue]) {}
+  }
+
+  private class NoopLongCounter : LongCounter {
+    func add(value: Int) {}
+    func add(value: Int, attribute: [String : AttributeValue]) {}
+  }
+
+  private class NoopLongCounterBuilder : LongCounterBuilder {
+    func ofDoubles() -> DoubleCounterBuilder {
+      NoopDoubleCounterBuilder()
+    }
+
+    func build() -> LongCounter {
+      NoopLongCounter()
+    }
+
+    func buildWithCallback(_ callback: @escaping (ObservableLongMeasurement) -> Void) -> ObservableLongCounter {
+      NoopObservableLongCounter()
+    }
+  }
+
+  private class NoopDoubleCounterBuilder : DoubleCounterBuilder {
+    func build() -> DoubleCounter {
+      StableNoopDoubleCounter()
+    }
+
+    func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement) -> Void) -> ObservableDoubleCounter {
+      NoopObservableDoubleCounter()
+    }
+  }
+
+  private class NoopObservableLongCounter : ObservableLongCounter {}
+  private class NoopObservableDoubleCounter: ObservableDoubleCounter {}
+
+  private class StableNoopDoubleCounterBuilder : DoubleCounterBuilder {
+    func build() -> DoubleCounter {
+      StableNoopDoubleCounter()
+    }
+
+    func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement) -> Void) -> ObservableDoubleCounter {
+      NoopObservableDoubleCounter()
+    }
+  }
+
+  private class StableNoopDoubleCounter : DoubleCounter {
+    func add(value: Double) {}
+    func add(value: Double, attributes: [String : AttributeValue]) {}
+  }
+}
+
+
+
+
+
+

Sources/OpenTelemetryApi/Metrics/Stable/DefaultStableMeterProvider.swift

@@ -1,62 +1,41 @@
-////
-//// Copyright The OpenTelemetry Authors
-//// SPDX-License-Identifier: Apache-2.0
-//// 
 //
-//import Foundation
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
 //
-//public class DefaultStableMeterProvider: StableMeterProvider {
-//    static var proxyMeter = StableProxyMeter()
-//    static var proxyMeterBuilder = ProxyMeterBuilder()
-//    static var initialized = false
-//    
-//    class StableProxyMeter : StableMeter {
-//        func counterBuilder(name: String) -> LongCounterBuilder {
-//        }
-//        
-//        func upDownCounterBuilder(name: String) -> LongUpDownCounterBuilder {
-//        }
-//        
-//        func histogramBuilder(name: String) -> DoubleHistogramBuilder {
-//        }
-//        
-//        func gaugeBuilder(name: String) -> DoubleGaugeBuilder {
-//        }
-//    }
-//    
-//    class ProxyMeterBuilder :  MeterBuilder {
-//        func setSchemaUrl(schemaUrl: String) -> Self {
-//            return self
-//        }
-//        
-//        func setInstrumentationVersion(instrumentationVersion: String) -> Self {
-//            return self
-//        }
-//        
-//        func build() -> StableMeter {
-//            return DefaultStableMeterProvider.proxyMeter
-//        }
-//        
-//    
-//    init() {}
-//    
-//    public static func setDefault(meterFactory: StableMeterProvider) {
-//        guard !initialized else {
-//            return
-//        }
-//        instance = meterFactory
-//        proxyMeter.updateMeter(realMeter: meterFactory.get(name: ""))
-//        initialized = true
-//    }
-//    
-//    public func get(name: String) -> StableMeter {
-//        return Self.initialized ? Self.instance.get(name: name) : Self.proxyMeter
-//    }
-//    
-//    public func meterBuilder(name: String) -> MeterBuilder {
-//        return Self.initialized ? self.instance.meterBuilder(name: name) : return Self.proxyMeterBuilder
-//        
-//    }
-//    
-//    public static var instance : StableMeterProvider = DefaultStableMeterProvider()
-//}
+
+import Foundation
+
+public class DefaultStableMeterProvider: StableMeterProvider {
+  static let noopMeterBuilder = NoopMeterBuilder()
+
+  public static func noop() -> MeterBuilder {
+    noopMeterBuilder
+  }
+
+  public func get(name: String) -> StableMeter {
+    DefaultStableMeter()
+  }
+
+  public func meterBuilder(name: String) -> MeterBuilder {
+    Self.noop()
+  }
+
+  class NoopMeterBuilder : MeterBuilder {
+    static let noopMeter = DefaultStableMeter()
+
+    func setSchemaUrl(schemaUrl: String) -> Self {
+      self
+    }
+
+    func setInstrumentationVersion(instrumentationVersion: String) -> Self {
+      self
+    }
+
+    func build() -> StableMeter {
+      Self.noopMeter
+    }
+
+  }
+
+    public static var instance : StableMeterProvider = DefaultStableMeterProvider()
+}

Sources/OpenTelemetryApi/Metrics/Stable/DoubleCounter.swift

@@ -7,6 +7,5 @@ import Foundation
 
 public protocol DoubleCounter {
     mutating func add(value: Double)
-
     mutating func add(value: Double, attributes: [String: AttributeValue])
 }

Sources/OpenTelemetryApi/Metrics/Stable/DoubleCounterBuilder.swift

@@ -5,8 +5,8 @@
 
 import Foundation
 
-public protocol DoubleCounterBuilder {
+public protocol DoubleCounterBuilder : AnyObject {
     func build() -> DoubleCounter
 
-    mutating func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement) -> Void) -> ObservableDoubleCounter
+    func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement) -> Void) -> ObservableDoubleCounter
 }

Sources/OpenTelemetryApi/Metrics/Stable/DoubleGaugeBuilder.swift

@@ -5,7 +5,7 @@
 
 import Foundation
 
-public protocol DoubleGaugeBuilder {
+public protocol DoubleGaugeBuilder : AnyObject {
     func ofLongs() -> LongGaugeBuilder
-    mutating func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement)->Void) -> ObservableDoubleGauge
+    func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement)->Void) -> ObservableDoubleGauge
 }

Sources/OpenTelemetryApi/Metrics/Stable/DoubleHistogramBuilder.swift

@@ -5,7 +5,7 @@
 
 import Foundation
 
-public protocol DoubleHistogramBuilder {
+public protocol DoubleHistogramBuilder : AnyObject {
     func ofLongs() -> LongHistogramBuilder
 
     func build() -> DoubleHistogram

Sources/OpenTelemetryApi/Metrics/Stable/DoubleUpDownCounterBuilder.swift

@@ -5,9 +5,9 @@
 
 import Foundation
 
-public protocol DoubleUpDownCounterBuilder {
+public protocol DoubleUpDownCounterBuilder : AnyObject {
     func build() -> DoubleUpDownCounter
-    mutating func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement) -> Void) -> ObservableDoubleUpDownCounter
+    func buildWithCallback(_ callback: @escaping (ObservableDoubleMeasurement) -> Void) -> ObservableDoubleUpDownCounter
 
 }