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on(event, handler)
Registers a handler to be called whenever the specified event occurs.
Parameter | Type | Default | Description |
---|---|---|---|
event | string | '' | Event to attach the handler to. Currently, only the 'console' event is supported. |
handler | function | null | A function to be called every time the specified event is emitted. |
Caution
When using thepage.on
method, the page has to be explicitly closed for the iteration to be able to finish.
Events
Event | Description |
---|---|
console | Emitted every time the console API methods are called from within the page JavaScript context. The arguments passed into the handler are defined by the ConsoleMessage class. |
Example
JavaScript
import { browser } from 'k6/x/browser';
import { check } from 'k6';
export const options = {
scenarios: {
ui: {
executor: 'shared-iterations',
options: {
browser: {
type: 'chromium',
},
},
},
},
thresholds: {
checks: ['rate==1.0'],
},
};
export default async function () {
const page = browser.newPage();
try {
await page.goto('https://test.k6.io/');
page.on('console', (msg) => {
check(msg, {
assertConsoleMessageType: (msg) => msg.type() == 'log',
assertConsoleMessageText: (msg) => msg.text() == 'this is a console.log message 42',
assertConsoleMessageArgs0: (msg) =>
msg.args()[0].jsonValue() == 'this is a console.log message',
assertConsoleMessageArgs1: (msg) => msg.args()[1].jsonValue() == 42,
});
});
page.evaluate(() => console.log('this is a console.log message', 42));
} finally {
page.close(); // required so iteration can end
}
}
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