Null Pointer Micromanagement
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    0.2.0 • Public • Published


    llog is a simple logging module. llog is intended for use in applications, not libraries. It provides level-based debugging (trace|debug|info|warn|error|fatal). note: For adding detailed debug statements in libraries, use TJ'sdebugmodule.

    As an added bonus, llog provides a simple upgrade path from plain text to json logging via either pino or bunyan. llog will look for pino or bunyan at load time and automatically use them as a provider if present. This means you can write your apps with non-json logging when starting, and auto-magically all your logs to json logging with a simple npm i --save pino.

    level-based debugging

    To use llog:

    var log = require('llog');
    log.debug('some info'); // prints 'debug some info' to stdout'some info'); // prints 'info some info' to stdout
    log.warn('some info'); // prints 'warn some info' to stdout
    log.error('some error'); // prints 'error some error' to stdout

    Specifying log levels

    llog is based on debug, and as such extends the same mechanism debug uses to specify which items to log - using process.env.DEBUG.

    To log only info, warn, and error in llog, for instance, you would run your application similar to the following:

    DEBUG=info,warn,error node app.js

    Adding trace is simple:

    DEBUG=trace,info,warn,error node app.js

    Magic upgrade to json logging

    llog will automatically detect if bunyan or pino are installed as a peer dependency and, if so, automatically upgrade to json logging. Because bunyan and pino use process.env.LOG_LEVEL as a level indicator (as opposed to debug's DEBUG variable, the steps for moving to json logs are:

    1. npm install --save buynan or npm install --save pino
    2. execute your application using LOG_LEVEL=10 node app instead of using DEBUG. Higher levels are always included when specifying a level.

    Bunyan log levels can be found at Pino log levels can be found at

    This is particularly useful when moving from early stages of application development to having unified logging via Logstash or Splunk.




    npm i llog

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