This is documentation for the next version of K6. For the latest stable release, go to the latest version.

Documentation

ReadableStreamDefaultController

error(reason)

Open source

error(reason)

The error() method of the ReadableStreamDefaultController makes any future interactions with the associated stream to error.

Parameters

Name	Type	Description
e	any	The error to return to any future interactions with the stream.

Exceptions

Exception	Description
TypeError	Thrown when the source object is not a ReadableStreamDefaultController.

Example

import { ReadableStream } from 'k6/experimental/streams';
import { setTimeout } from 'k6/timers';

export default async function () {
  let currentNumber = 0;

  const stream = new ReadableStream({
    start(controller) {
      const fn = () => {
        if (currentNumber % 8 == 0) {
          // Error the stream when the number is divisible by 8
          controller.error('erroring the stream because we received a multiple of 8');
          return;
        }

        if (currentNumber < 10) {
          controller.enqueue(++currentNumber);
          setTimeout(fn, 1000);
          return;
        }

        controller.close();
      };
      setTimeout(fn, 1000);
    },
  });

  const reader = stream.getReader();

  while (true) {
    const { done, value } = await reader.read();
    if (done) break;
    console.log(`received number ${value} from stream`);
  }
}