makrut v1.0.2

Makrut

Yes, this is another javascript logger, but this one is tiny and functional.

Quickstart

Install Makrut:

npm install makrut

Use Makrut:

import makrut from "makrut";

// Supported levels are: trace, debug, info, warn, error
const logger = makrut("info");

logger.debug("This won't print because 'debug' is more verbose than 'info'.");
logger.info("This will print");
try {
  theImpossible();
} catch (error) {
  logger.error("This will print too, and so will the error", error);
}

Prerequisites

Since this is an es6 module only, it requires Node.js >= 12.17.0 (LTS) or >= 13.2.0, the --experimental-modules flag, or an alternative module loader. There are zero npm dependencies.

API

Initialisation

A logger instance is created in Makrut by calling the single function returned as the default import.

import makrut from 'makrut';
const logger = makrut(level);

Input:

level Optional string from 'trace', 'debug', 'info', 'warn', 'error' (not case sensitive), defaults to 'info'.

Returns: An object of the following form. Each key is a callable logging function.

{
  trace: [Function],
  debug: [Function],
  info: [Function],
  warn: [Function],
  error: [Function]
};

Logging

Logging is done by calling one of the functions on the returned logger object:

logger.trace(message, data);
logger.debug(message, data);
logger.info(message, data);
logger.warn(message, data);
logger.error(message, data);

These are listed in increasing verbosity order, Makrut will only print messages that are equal or less verbose than the level you originally provided on initialisation. The corresponding function from console is used for each level, meaning that logger.trace will include the stacktrace of the calling context and logger.error will output to stderr.

Input:

message A string to print out to the console.

data Optional additional data to print after the message. This is printed by console.dir, so it would bypass any inspect() method on the data.

Returns: Nothing.

Inspect

Makrut allows you to easily log objects in a promise or map chain using the inspect function:

logger.trace.inspect(message)(data);
logger.debug.inspect(message)(data);
logger.info.inspect(message)(data);
logger.warn.inspect(message)(data);
logger.error.inspect(message)(data);
// or
logger.trace.inspect(data);
logger.debug.inspect(data);
logger.info.inspect(data);
logger.warn.inspect(data);
logger.error.inspect(data);

This is mathematically an identity function with a side effect, i.e. it returns the value it was called with, and logs it to the console.

Input:

message An optional string to print out before the object.

data An object to print after the message. This is printed by console.dir, so it would bypass any inspect() method on the data. If this will be a string, then a blank message must be provided or the data will be interpreted as the message.

Returns: data

This gives you some options when inspecting data in a chain of .map functions or promises. Each level has an accompanying inspect function, which will only log something if that level would output something. Note that the identity behaviour of returning the input remains while the log level is disabled so that it is safe to have in a map/promise chain still.

Example:

import makrut from "makrut";
const logger = makrut("debug");

const numbersPlus10 = [1, 2, 3]
  .map(logger.debug.inspect)
  .map(x => x + 10)
  .map(logger.info.inspect("after adding 10"));

/* Output:
DEBUG:
1
DEBUG:
2
DEBUG:
3
INFO: after adding 10
11
INFO: after adding 10
12
INFO: after adding 10
13
*/

new Promise((resolve, reject) => resolve("Hello World"))
  .then(logger.info.inspect(""));

/* Output:
INFO: 
Hello World
*/

Development

Get started by cloning this repo and installing the development dependencies:

git clone git+https://github.com/frogamic/makrut
npm install

There are currently no tests, but there linting is set up with eslint. I am using lightly customized airbnb-base rules, check .eslint.cjs for the full definition.

npm run lint

What is a Makrut

The makrut lime is widely known as the kaffir lime, however the k word is an offensive racial slur in parts of Africa.