Registry / observability / lighthouse-logger

lighthouse-logger

library2.0.2jsnpmunverified

The `lighthouse-logger` package provides a shared logging utility class primarily used internally by the Google Lighthouse project and its associated tools. It offers basic logging capabilities with a focus on integrating within the Lighthouse ecosystem. The current stable version is 2.0.2, last published 8 months ago, and it ships with TypeScript types for improved developer experience. While the broader Lighthouse project updates frequently with Chrome DevTools releases, `lighthouse-logger` maintains a more independent and slower release cycle. Its key differentiators include its tight integration with Lighthouse's internal architecture and its minimal set of dependencies, notably `debug` and `marky`. However, discussions within the Lighthouse team suggest that maintaining `lighthouse-logger` as an external npm package is considered "awkward," and there's consideration for deprecating its external use, potentially leading to a maintenance-only status or advising direct internal referencing for Lighthouse itself.

observability

npm install lighthouse-logger

github ↗package ↗

INSTALL

IMPORT

SIG · LIGHTHOUSE-LOGGER

lighthouse-logger

observabilityjavascriptv2.0.2

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Logger

✓ import { Logger } from 'lighthouse-logger';

✗ const Logger = require('lighthouse-logger');

The primary export is a Logger class. Version 2.x is designed for ES Modules.

setLevel

✓ import { setLevel } from 'lighthouse-logger';

✗ const { setLevel } = require('lighthouse-logger');

A utility function to control the logging verbosity programmatically. ESM-only.

✓ import * as LighthouseLogger from 'lighthouse-logger';

✗ import LighthouseLogger from 'lighthouse-logger';

There is no default export; all utilities are named exports. CommonJS requires the `require()` syntax.

Demonstrates how to import the Logger class, set its logging level, and use various logging methods.

import { Logger, setLevel } from 'lighthouse-logger'; // Set the desired logging level (e.g., 'verbose', 'log', 'info', 'warn', 'error', 'silent') // By default, it might log based on debug environment variables or a default level. setLevel('verbose'); const myLogger = new Logger('my-app'); myLogger.log('Starting application...'); myLogger.info('Configuration loaded successfully.'); myLogger.warn('Potential issue: API endpoint might be deprecated.'); myLogger.error('Critical error: Failed to connect to database!'); // Example of more detailed logging with specific log IDs myLogger.log('Processing data for user', { userId: 123, dataSize: '1.5MB' }); // You can also create sub-loggers for different modules const dataProcessorLogger = new Logger('my-app:data-processor'); dataProcessorLogger.verbose('Entering data processing module.'); // Example of setting level via environment variable for Node.js // process.env.DEBUG = 'my-app*' // This would enable debug logs for 'my-app' namespace console.log('\nCheck your console output for logs. Note: ' + 'Actual output depends on environment variables (e.g., DEBUG) and setLevel call.');

Debug

Known issues

gotchaThe `lighthouse-logger` package is internally managed within the Lighthouse monorepo and has been described as an 'awkward package to maintain' for external consumption. While currently available on npm, future external support or major updates might be limited, or the Lighthouse project might advise against its direct external use. Consider its 'maintenance' status when integrating into new projects.

fix

Review the latest Lighthouse project guidelines for logging if you intend to use it in a related project, or consider a more general-purpose logging library for independent applications.

affects: >=2.0.0

breakingVersion 2.x of `lighthouse-logger` is primarily distributed as an ES Module (ESM). Attempting to import it using CommonJS `require()` syntax in a Node.js environment configured for ESM or in a browser context might lead to errors.

fix

Ensure your project uses ES Module import syntax (`import { Logger } from 'lighthouse-logger';`) and your Node.js environment is configured for ESM (e.g., `"type": "module"` in `package.json` or `.mjs` file extension).

affects: >=2.0.0

Errors

Common errors & fixes

ERR_REQUIRE_ESM: require() of ES Module .../node_modules/lighthouse-logger/index.js from .../my-app.js not supported

Attempting to import `lighthouse-logger` (an ES Module) using CommonJS `require()` in a context where only ESM is expected or configured.

fix

Change your import statement to use ES Modules: `import { Logger } from 'lighthouse-logger';`. If in Node.js, ensure your `package.json` has `"type": "module"` or use `.mjs` file extensions for your module.

TypeError: Logger is not a constructor

The `Logger` class might not be correctly imported or accessed, often due to incorrect import syntax for named exports.

fix

Ensure you are using named imports for `Logger`: `import { Logger } from 'lighthouse-logger';`. Avoid `import Logger from 'lighthouse-logger';` as it is not a default export.

Upgrade

Version history

2.0.2latest on npm

Audit

Dependencies

debugrequiredUsed for conditional debug logging.

markyrequiredUsed for performance marking and measurements within the logger.

Agent activity

11 hits · last 30 days

node

OpenAI (training)

Amazon

Resources

githubhttps://github.com/GoogleChrome/lighthouse ↗

packagehttps://www.npmjs.com/package/lighthouse-logger ↗