nodeutils

My node helpers

Install

npm i --save https://github.com/fpercival/nodeutils.git

Usage

extend

Extend object from other objects

let extend = require('nodeutils').extend;

let dest = {x:4, y:20};
extend(dest, {z:20}, {y:5});

assert.equal(dest.y, 5);
assert.equal(dest.z, 20);

nextr

Ensures functions are called synchronously.

Signature: nextr( items, eachFunc, doneFunc )

-items: Array of items to be processed

-eachFunc: function called for each item. Function is passed the current item and a function to call when processing is complete. If the 'next' function is passed 'true', the processing is cancelled and doneFunc is called if provided.

-doneFunc: (optional) function called after all items have been processed.

let nextr = require('nodeutils').nextr;

const arr = [1, 2, 5, 4];
let res = '';
nextr(
    arr,
    function(item, next){
        setTimeout( function(){
            res = res + item;
            console.log(res);
            next();
        }, 100);
    },
    function(){
        console.log('result: '+res);
    },
);
// Prints
// '1'
// '12'
// '125'
// '1254'
// 'result: 1254'

log

A scoped logger that can filtered globally or within each scope.

Global logger

The global logger emits events for messages based on level.

let logger = require('nodeutils').log;

function toConsole(){ console.log.apply(console, arguments); };

logger.on('debug', toConsole );
logger.on('warn', toConsole );
logger.on('info', toConsole );
logger.on('error', toConsole );

Scoped logger

let log1 = logger.create('log:scope1');
log1.debug('debug info');
log1.warn('Watch out !!');
log1.info('FYI');
log1.error('Something went wrong', new Error('oops') );

Set logging level

Log level can be set globally or seperately per scope. Default level is 'debug'

logger.setLevel('debug');  // emits debug, warn, info & error
logger.setLevel('warn');  // emits warn, info & error
logger.setLevel('info');  // emits info & error
logger.setLevel('error');  // emits error
logger.setLevel('none');  // emits no messages

Filtering

Messages can be filtered based on the scope name.

let log1 = logger.create('log:scope1');
let log2 = logger.create('log:scope2');

// Using a wildcard
logger.setFilter('log:*'); // Will emit messages from log1 & log2
logger.setFilter('*scope2'); // Will only emit messages from log2

Accessing

Scope loggers can be accessed from the global logger by name.

 logger.get( 'log:scope1' ,
    scopeLogger => {
        acopeLogger.setFilter('*');
    }
 );

or using a regular expression

 logger.get( /log.*/i ,
    scopeLogger => {
        acopeLogger.setFilter('*');
    }
 );