@dash0/sdk-web/src/transport/index.ts

Dash0's Web SDK to collect telemetry from end-users' web browsers

import { newBatcher } from "./batcher";
import { send } from "./fetch";
import { vars } from "../vars";
import { debug, error, createRateLimiter } from "../utils";
import { ExportLogsServiceRequest, ExportTraceServiceRequest, LogRecord, Span } from "../types/otlp";

const logBatcher = newBatcher<LogRecord>(sendLogs);
const spanBatcher = newBatcher<Span>(sendSpans);

let rateLimiter: (() => boolean) | undefined;

function isRateLimited() {
  if (!rateLimiter) {
    rateLimiter = createRateLimiter({
      maxCallsPerTenMinutes: 4096,
      maxCallsPerTenSeconds: 128,
    });
  }

  return rateLimiter();
}

export function sendLog(log: LogRecord): void {
  if (isRateLimited()) {
    debug("Transport rate limit. Will not send item.", log);
    return;
  }

  logBatcher.send(log);
}

function sendLogs(logs: LogRecord[]): void {
  send("/v1/logs", {
    resourceLogs: [
      {
        resource: vars.resource,
        scopeLogs: [
          {
            scope: vars.scope,
            logRecords: logs,
          },
        ],
      },
    ],
  } satisfies ExportLogsServiceRequest).catch((err) => {
    error("Failed to transmit logs", err);
  });
}

export function sendSpan(span: Span | undefined): void {
  if (!span) return;

  if (isRateLimited()) {
    debug("Transport rate limit. Will not send item.", span);
    return;
  }

  spanBatcher.send(span);
}

function sendSpans(spans: Span[]): void {
  send("/v1/traces", {
    resourceSpans: [
      {
        resource: vars.resource,
        scopeSpans: [
          {
            scope: vars.scope,
            spans: spans,
          },
        ],
      },
    ],
  } satisfies ExportTraceServiceRequest).catch((err) => {
    error("Failed to transmit spans", err);
  });
}