Emcee

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import DateProvider
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import Foundation
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import Metrics
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import MetricsExtensions
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import QueueModels
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import Timer
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import WorkerAlivenessModels
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import WorkerAlivenessProvider
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public final class WorkerAlivenessMetricCapturer {
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    private let dateProvider: DateProvider
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    private let timer: DispatchBasedTimer
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    private let queueHostname: String
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    private let version: Version
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    private let workerAlivenessProvider: WorkerAlivenessProvider
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    private let globalMetricRecorder: GlobalMetricRecorder
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    public init(
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        dateProvider: DateProvider,
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        reportInterval: DispatchTimeInterval,
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        queueHostname: String,
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        version: Version,
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        workerAlivenessProvider: WorkerAlivenessProvider,
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        globalMetricRecorder: GlobalMetricRecorder
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    ) {
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        self.dateProvider = dateProvider
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        self.timer = DispatchBasedTimer(repeating: reportInterval, leeway: .seconds(1))
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        self.queueHostname = queueHostname
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        self.version = version
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        self.workerAlivenessProvider = workerAlivenessProvider
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        self.globalMetricRecorder = globalMetricRecorder
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    }
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    public func start() {
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        timer.start { [weak self] timer in
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            guard let strongSelf = self else {
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                return timer.stop()
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            }
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            let aliveness = strongSelf.workerAlivenessProvider.workerAliveness
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            strongSelf.captureMetrics(aliveness: aliveness)
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        }
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    }
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    public func stop() {
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        timer.stop()
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    }
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    private func captureMetrics(
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        aliveness: [WorkerId: WorkerAliveness]
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    ) {
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        let metrics: [WorkerStatusMetric] = aliveness.map {
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            WorkerStatusMetric(
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                workerId: $0.key,
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                status: $0.value.metricComponentName,
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                version: version,
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                queueHost: queueHostname,
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                timestamp: dateProvider.currentDate()
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            )
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        }
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        globalMetricRecorder.capture(metrics)
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    }
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}
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private extension WorkerAliveness {
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    var metricComponentName: String {
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        if !registered { return "notRegistered" }
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        if disabled { return "disabled" }
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        if silent {
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            return "silent"
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        } else {
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            return "alive"
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        }
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    }
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}
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