cypress-log-to-output

What is cypress-log-to-output?

The cypress-log-to-output npm package allows you to capture and output Cypress logs to the terminal or other output streams. This is particularly useful for debugging and monitoring tests in CI environments where you may not have access to the browser's console.

What are cypress-log-to-output's main functionalities?

Log to Terminal

This feature allows you to capture Cypress logs and print them directly to the terminal. This is useful for debugging tests in environments where you don't have access to the browser's console.

const installLogsPrinter = require('cypress-log-to-output').install;

installLogsPrinter();

Custom Log Filtering

This feature allows you to filter logs based on custom criteria. In this example, only logs that contain the word 'error' will be printed to the terminal.

const installLogsPrinter = require('cypress-log-to-output').install;

installLogsPrinter({
  filterLog: (log) => log.message.includes('error')
});

Log to File

This feature allows you to capture Cypress logs and write them to a file. This is useful for keeping a persistent record of logs for later analysis.

const fs = require('fs');
const installLogsPrinter = require('cypress-log-to-output').install;

installLogsPrinter({
  printLogsToFile: 'cypress-logs.txt'
});

Other packages similar to cypress-log-to-output

cypress-failed-log

The cypress-failed-log package captures logs for failed Cypress tests and saves them to a file. Unlike cypress-log-to-output, it focuses specifically on failed tests and provides detailed logs for debugging.

cypress-terminal-report

The cypress-terminal-report package captures Cypress logs and outputs them to the terminal, similar to cypress-log-to-output. However, it also provides additional features like grouping logs by test and adding custom log messages.

README

cypress-log-to-output

This is a Cypress plugin that sends all console logs that occur in the browser to stdout in the terminal. This means that you can see any kind of console.log, console.info or console.error that occurs in the browser, even if your tests are running in the terminal.

Installation

npm install --save-dev cypress-log-to-output

Usage

In your cypress/plugins/index.js, add this to your module.exports:

module.exports = (on, config) => {
  /** the rest of your plugins... **/
  require('cypress-log-to-output').install(on)
  // or, if there is already a before:browser:launch handler, use .browserLaunchHandler inside of it
  // @see https://github.com/flotwig/cypress-log-to-output/issues/5
}

You'll now see all browser console logs in your terminal output.

cypress run --browser=chrome

Works in Chrome, Chromium, or Canary browsers during cypress run and cypress open.

Electron is not currently supported. I can't find a way to attach the Chrome Debugging Protocol to the Electron browser spawned by Cypress.

Filtering Events

If you want to filter events, you can use a custom filtering callback:

module.exports = (on, config) => {
  /** the rest of your plugins... **/
  require('cypress-log-to-output').install(on, (type, event) => {
    // return true or false from this plugin to control if the event is logged
    // `type` is either `console` or `browser`
    // if `type` is `browser`, `event` is an object of the type `LogEntry`:
    //  https://chromedevtools.github.io/devtools-protocol/tot/Log#type-LogEntry
    // if `type` is `console`, `event` is an object of the type passed to `Runtime.consoleAPICalled`:
    //  https://chromedevtools.github.io/devtools-protocol/tot/Runtime#event-consoleAPICalled

    // for example, to only show error events:

    if (event.level === 'error' || event.type === 'error') {
      return true
    }

    return false
  })
}

Recording Logs

If you want to record the logs internally, you can use the recordLogs option:

module.exports = (on, config) => {
  /** the rest of your plugins... **/
  const options = { recordLogs: true };
  require('cypress-log-to-output').install(on, filterCallback, options)
}

The logs will be stored in an internal buffer. They can be accessed using the getLogs exported function. The buffer can be cleared using the clearLogs exported function.

Disabling debug info

You can remove the lines beginning with [cypress-log-to-output] by passing -cypress-log-to-output in the DEBUG environment variable.