rclnodejs/test_repro_sub.js

ROS2.0 JavaScript client with Node.js

// Subscriber for repro test - runs in separate process
'use strict';

const rclnodejs = require('./index.js');

async function main() {
  await rclnodejs.init();

  const node = new rclnodejs.Node('test_subscriber_node');

  let msgCount = 0;
  let lastTs = null;
  const hzSamples = [];
  let startTime = null;

  node.createSubscription(
    'std_msgs/msg/Float64MultiArray',
    '/test_hz_topic',
    (msg) => {
      const now = Date.now();
      msgCount++;
      if (!startTime) startTime = now;
      if (lastTs) {
        const hz = 1000 / (now - lastTs);
        hzSamples.push(hz);
        if (msgCount % 50 === 0) {
          const recentSamples = hzSamples.slice(-50);
          const recentAvg =
            recentSamples.reduce((a, b) => a + b, 0) / recentSamples.length;
          console.log(
            `msg#${msgCount} recent avg Hz: ${recentAvg.toFixed(2)}`
          );
        }
      }
      lastTs = now;
    }
  );

  node.spin();

  setTimeout(() => {
    if (hzSamples.length > 0) {
      const avgHz =
        hzSamples.reduce((a, b) => a + b, 0) / hzSamples.length;
      const minHz = Math.min(...hzSamples);
      const maxHz = Math.max(...hzSamples);
      const elapsed = (Date.now() - startTime) / 1000;

      console.log(`\n--- Results ---`);
      console.log(`Received:   ${msgCount} messages in ${elapsed.toFixed(1)}s`);
      console.log(`Avg Hz:     ${avgHz.toFixed(2)}`);
      console.log(`Min Hz:     ${minHz.toFixed(2)}`);
      console.log(`Max Hz:     ${maxHz.toFixed(2)}`);
    } else {
      console.log('No messages received!');
    }

    node.stop();
    rclnodejs.shutdown();
    process.exit(0);
  }, 12000);
}

main().catch(console.error);