nx/docs/shared/packages/cypress/cypress-setup-node-events.md

Using setupNodeEvents with Cypress preset

The setupNodeEvents function in a Cypress configuration file allows you to tap into the internal behavior of Cypress using the on and config arguments.

import { defineConfig } from 'cypress';

export default defineConfig({
  e2e: {
    setupNodeEvents(on, config) {
      // e2e testing node events setup code
    },
  },
});

The Cypress preset that Nx provides (@nx/cypress/plugins/cypress-preset) uses setupNodeEvents to start the web server. Thus, if you provide your own function, then you must invoke the setupNodeEvents function that our preset provides.

import { defineConfig } from 'cypress';
import { nxE2EPreset } from '@nx/cypress/plugins/cypress-preset';

const config = nxE2EPreset(__filename, {
  cypressDir: 'src',
  bundler: 'vite',
  webServerCommands: {
    default: 'nx run my-project:serve',
    production: 'nx run my-project:preview',
  },
  ciWebServerCommand: 'nx run my-project:serve-static',
});

export default defineConfig({
  e2e: {
    ...config,
    async setupNodeEvents(on, config) {
      // This line sets up the web server as provided via `webServerCommands` and `ciWebServerCommand`
      await config.setupNodeEvents(on, config);

      // Register your listeners here
    },
  },
});

{% callout type="note" title="Note on async-await" %} The setupNodeEvents function from our Cypress preset returns a promise, so make sure to await the result. {% /callout %}