error(reason)
Documentation
Grafana k6
JavaScript API
k6/experimental
streams
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
JavaScript
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`);
}
}
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