Logging in both Node and the browser the less fancy way

Usage no npm install needed!

<script type="module">
  import logLessFancy from 'https://cdn.skypack.dev/log-less-fancy';



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Logging in both Node and the browser the fancy way using the debug module with an API that provides log levels.



npm i -S log-less-fancy


The package exports a single function, which takes the namespace of your module as an argument and returns the logger API.

// logger.js
const logger = require("log-less-fancy")("myNamespace");

logger.info("This is not a monolith, but your mother is");
logger.warn("oiii mate, watch out");
logger.debug("why is this even working?");
logger.error("dis is broke m8");
logger.fatal("shit went wrong D:");

Now execute the script:

# Prints all messages and all fatal errors
DEBUG='*' node logger.js

# Prints only warnings and all fatal errors
DEBUG=*WARN* node logger.js

# Prints only messages in your namespace and all fatal errors
DEBUG=*myNamespace* node logger.js

Node API

The logger API consists of 8 methods, namely fatal, error, success, warn, info, debug and log. All methods act like the native console API and take as many arguments as you like.

The fatal method is the only one with divergent behavior:

  • It traces the log up to the source file which triggered it which helps to debug the exception if necessary.
  • It will always be rendered and does not use the DEBUG environment variable / the debug module since it doesn't make sense to not to print fatal errors at any time.
  • It exits the process with code 1 which identifies the Node process as crashed.

Browser API

The logger API in the browser is aligned to the Node API, but only uses the native console object to save some bytes down the wire, so no debug fancy colored output here.

Advanved features and methods


Enforces the log output to be shown. Useful if you cannot set the DEBUG env variable yourself.

Roadmap / Features to develop

  • Add adapters / plugins, e.g. a plugin which forwards all messages to the fs or some logging service. #1
  • Make the configuration possible via a .fancylogrc which will be resolved from the root folder of the processes package . #2

Code style

Please make sure that you adhere to the code style which is based upon xo.


See the LICENSE file at the root of the repository.