Class OpenTelemetry

packages/server/src/metrics/OpenTelemetry.ts:12–257

const createdMetrics = new Map<string, boolean>()

export class OpenTelemetry implements IMetricsProvider {
    private app: express.Application
    private resource: Resource
    private otlpMetricExporter: any
    // private otlpTraceExporter: any
    // private tracerProvider: NodeTracerProvider
    private metricReader: PeriodicExportingMetricReader
    private meterProvider: MeterProvider

    // Map to hold all counters and histograms
    private counters = new Map<string, Counter | Histogram>()
    private httpRequestCounter: Counter
    private httpRequestDuration: any

    constructor(app: express.Application) {
        this.app = app

        if (!process.env.METRICS_OPEN_TELEMETRY_METRIC_ENDPOINT) {
            throw new Error('METRICS_OPEN_TELEMETRY_METRIC_ENDPOINT is not defined')
        }

        if (process.env.METRICS_OPEN_TELEMETRY_DEBUG === 'true') {
            diag.setLogger(new DiagConsoleLogger(), DiagLogLevel.DEBUG)
        }

        // Clear metrics tracking on new instance
        createdMetrics.clear()
    }

    public getName(): string {
        return 'OpenTelemetry'
    }

    async initializeCounters(): Promise<void> {
        try {
            // Define the resource with the service name for trace grouping
            const flowiseVersion = await getVersion()

            this.resource = new Resource({
                [ATTR_SERVICE_NAME]: process.env.METRICS_SERVICE_NAME || 'FlowiseAI',
                [ATTR_SERVICE_VERSION]: flowiseVersion.version // Version as a label
            })

            const metricProtocol = process.env.METRICS_OPEN_TELEMETRY_PROTOCOL || 'http' // Default to 'http'
            // Conditionally import the correct OTLP exporters based on protocol
            let OTLPMetricExporter
            if (metricProtocol === 'http') {
                OTLPMetricExporter = require('@opentelemetry/exporter-metrics-otlp-http').OTLPMetricExporter
            } else if (metricProtocol === 'grpc') {
                OTLPMetricExporter = require('@opentelemetry/exporter-metrics-otlp-grpc').OTLPMetricExporter
            } else if (metricProtocol === 'proto') {
                OTLPMetricExporter = require('@opentelemetry/exporter-metrics-otlp-proto').OTLPMetricExporter
            } else {
                console.error('Invalid METRICS_OPEN_TELEMETRY_PROTOCOL specified. Please set it to "http", "grpc", or "proto".')
                process.exit(1) // Exit if invalid protocol type is specified
            }

            // Handle any existing metric exporter