chore: import upstream snapshot with attribution

2026-07-13 13:32:57 +08:00
commit cd420f9332
4811 changed files with 884702 additions and 0 deletions
@@ -0,0 +1,153 @@
+import { type ExportResult, ExportResultCode } from "@opentelemetry/core";
+import type {
+  PushMetricExporter,
+  ResourceMetrics,
+  MetricData,
+  DataPoint,
+  Histogram,
+  ExponentialHistogram,
+} from "@opentelemetry/sdk-metrics";
+
+/**
+ * Compact metric exporter that logs metrics in a single-line format
+ * Similar to Prometheus text format for better readability
+ */
+export class CompactMetricExporter implements PushMetricExporter {
+  /**
+   * Export metrics in a compact format
+   */
+  export(metrics: ResourceMetrics, resultCallback: (result: ExportResult) => void): void {
+    try {
+      this._exportMetrics(metrics);
+      resultCallback({ code: ExportResultCode.SUCCESS });
+    } catch (error) {
+      resultCallback({
+        code: ExportResultCode.FAILED,
+        error: error instanceof Error ? error : new Error(String(error)),
+      });
+    }
+  }
+
+  /**
+   * Shutdown the exporter
+   */
+  async shutdown(): Promise<void> {
+    return Promise.resolve();
+  }
+
+  /**
+   * Force flush any buffered data
+   */
+  async forceFlush(): Promise<void> {
+    return Promise.resolve();
+  }
+
+  /**
+   * Process and log metrics in compact format
+   */
+  private _exportMetrics(resourceMetrics: ResourceMetrics): void {
+    for (const scopeMetric of resourceMetrics.scopeMetrics) {
+      for (const metric of scopeMetric.metrics) {
+        this._exportMetric(metric);
+      }
+    }
+  }
+
+  /**
+   * Export a single metric
+   */
+  private _exportMetric(metric: MetricData): void {
+    const metricName = metric.descriptor.name;
+
+    for (const dataPoint of metric.dataPoints) {
+      const formattedLine = this._formatDataPoint(metricName, dataPoint);
+      if (formattedLine) {
+        console.log(formattedLine);
+      }
+    }
+  }
+
+  /**
+   * Format a data point into a single line
+   */
+  private _formatDataPoint(
+    metricName: string,
+    dataPoint: DataPoint<number> | DataPoint<Histogram> | DataPoint<ExponentialHistogram>
+  ): string | null {
+    // Extract attributes/labels
+    const labels = this._formatLabels(dataPoint.attributes);
+
+    // Extract value based on data point type
+    const value = this._extractValue(dataPoint);
+
+    if (value === null || value === undefined) {
+      return null;
+    }
+
+    // Format as: metric_name{label1="value1",label2="value2"} = value
+    if (labels) {
+      return `${metricName}{${labels}} = ${value}`;
+    }
+
+    return `${metricName} = ${value}`;
+  }
+
+  /**
+   * Format attributes as Prometheus-style labels
+   */
+  private _formatLabels(attributes: Record<string, unknown>): string {
+    const entries = Object.entries(attributes);
+    if (entries.length === 0) {
+      return "";
+    }
+
+    return entries.map(([key, value]) => `${key}="${String(value)}"`).join(",");
+  }
+
+  /**
+   * Extract the numeric value from a data point
+   */
+  private _extractValue(
+    dataPoint: DataPoint<number> | DataPoint<Histogram> | DataPoint<ExponentialHistogram>
+  ): number | null {
+    const value = dataPoint.value;
+
+    // Check if value is a simple number (Gauge, Sum, UpDownSum)
+    if (typeof value === "number") {
+      return value;
+    }
+
+    // Check if value is a Histogram or ExponentialHistogram
+    if (this._isHistogram(value) || this._isExponentialHistogram(value)) {
+      return value.sum ?? null;
+    }
+
+    return null;
+  }
+
+  /**
+   * Type guard for Histogram
+   */
+  private _isHistogram(value: unknown): value is Histogram {
+    return (
+      value !== null &&
+      typeof value === "object" &&
+      "sum" in value &&
+      "count" in value &&
+      "buckets" in value
+    );
+  }
+
+  /**
+   * Type guard for ExponentialHistogram
+   */
+  private _isExponentialHistogram(value: unknown): value is ExponentialHistogram {
+    return (
+      value !== null &&
+      typeof value === "object" &&
+      "sum" in value &&
+      "count" in value &&
+      "scale" in value
+    );
+  }
+}