hoek

General purpose node utilities

npm install hoek
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General purpose node utilities

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Introduction

The Hoek general purpose node utilities library is used to aid in a variety of manners. It comes with useful methods for Arrays (clone, merge, applyToDefaults), Objects (removeKeys, copy), Asserting and more.

For example, to use Hoek to set configuration with default options:

var Hoek = require('hoek');

var default = {url : "www.github.com", port : "8000", debug : true}

var config = Hoek.applyToDefaults(default, {port : "3000", admin : true});

// In this case, config would be { url: 'www.github.com', port: '3000', debug: true, admin: true }

Under each of the sections (such as Array), there are subsections which correspond to Hoek methods. Each subsection will explain how to use the corresponding method. In each js excerpt below, the var Hoek = require('hoek') is omitted for brevity.

Object

Hoek provides several helpful methods for objects and arrays.

clone(obj)

This method is used to clone an object or an array. A deep copy is made (duplicates everything, including values that are objects).


var nestedObj = {
        w: /^something$/ig,
        x: {
            a: [1, 2, 3],
            b: 123456,
            c: new Date()
        },
        y: 'y',
        z: new Date()
    };

var copy = Hoek.clone(nestedObj);

copy.x.b = 100;

console.log(copy.y)        // results in 'y'
console.log(nestedObj.x.b) // results in 123456
console.log(copy.x.b)      // results in 100

merge(target, source, isNullOverride, isMergeArrays)

isNullOverride, isMergeArrays default to true

Merge all the properties of source into target, source wins in conflic, and by default null and undefined from source are applied


var target = {a: 1, b : 2}
var source = {a: 0, c: 5}
var source2 = {a: null, c: 5}

var targetArray = [1, 2, 3];
var sourceArray = [4, 5];

var newTarget = Hoek.merge(target, source);     // results in {a: 0, b: 2, c: 5}
newTarget = Hoek.merge(target, source2);        // results in {a: null, b: 2, c: 5}
newTarget = Hoek.merge(target, source2, false); // results in {a: 1, b: 2, c: 5}

newTarget = Hoek.merge(targetArray, sourceArray)              // results in [1, 2, 3, 4, 5]
newTarget = Hoek.merge(targetArray, sourceArray, true, false) // results in [4, 5]

applyToDefaults(defaults, options)

Apply options to a copy of the defaults


var defaults = {host: "localhost", port: 8000};
var options = {port: 8080};

var config = Hoek.applyToDefaults(defaults, options); // results in {host: "localhost", port: 8080};

unique(array, key)

Remove duplicate items from Array


var array = [1, 2, 2, 3, 3, 4, 5, 6];

var newArray = Hoek.unique(array); // results in [1,2,3,4,5,6];

array = [{id: 1}, {id: 1}, {id: 2}];

newArray = Hoek.unique(array, "id") // results in [{id: 1}, {id: 2}]

mapToObject(array, key)

Convert an Array into an Object


var array = [1,2,3];
var newObject = Hoek.mapToObject(array); // results in [{"1": true}, {"2": true}, {"3": true}]

array = [{id: 1}, {id: 2}];
newObject = Hoek.mapToObject(array, "id") // results in [{"id": 1}, {"id": 2}]

intersect(array1, array2)

Find the common unique items in two arrays


var array1 = [1, 2, 3];
var array2 = [1, 4, 5];

var newArray = Hoek.intersect(array1, array2) // results in [1]

flatten(array, target)

Flatten an array


var array = [1, 2, 3];
var target = [4, 5];

var flattenedArray = Hoek.flatten(array, target) // results in [4, 5, 1, 2, 3];

reach(obj, chain, [options])

Converts an object key chain string to reference


var chain = 'a.b.c';
var obj = {a : {b : { c : 1}}};

Hoek.reach(obj, chain) // returns 1

Timer

A Timer object. Initializing a new timer object sets the ts to the number of milliseconds elapsed since 1 January 1970 00:00:00 UTC.


var timerObj = new Hoek.Timer();
console.log("Time is now: " + timerObj.ts)
console.log("Elapsed time from initialization: " + timerObj.elapsed() + 'milliseconds')

Bench

Same as Timer with the exception that ts stores the internal node clock which is not related to Date.now() and cannot be used to display human-readable timestamps. More accurate for benchmarking or internal timers.

Binary Encoding/Decoding

base64urlEncode(value)

Encodes value in Base64 or URL encoding

base64urlDecode(value)

Decodes data in Base64 or URL encoding.

Escaping Characters

Hoek provides convenient methods for escaping html characters. The escaped characters are as followed:


internals.htmlEscaped = {
    '&': '&',
    '<': '&lt;',
    '>': '&gt;',
    '"': '&quot;',
    "'": '&#x27;',
    '`': '&#x60;'
};

escapeHtml(string)


var string = '<html> hey </html>';
var escapedString = Hoek.escapeHtml(string); // returns &lt;html&gt; hey &lt;/html&gt;

escapeHeaderAttribute(attribute)

Escape attribute value for use in HTTP header


var a = Hoek.escapeHeaderAttribute('I said "go w\\o me"');  //returns I said \"go w\\o me\"

escapeRegex(string)

Escape string for Regex construction


var a = Hoek.escapeRegex('4^f$s.4*5+-_?%=#!:@|~\\/`"(>)[<]d{}s,');  // returns 4\^f\$s\.4\*5\+\-_\?%\=#\!\:@\|~\\\/`"\(>\)\[<\]d\{\}s\,

Errors

assert(message)


var a = 1, b =2;

Hoek.assert(a === b, 'a should equal b');  // ABORT: a should equal b

abort(message)

First checks if process.env.NODE_ENV === 'test', and if so, throws error message. Otherwise, displays most recent stack and then exits process.

displayStack(slice)

Displays the trace stack


var stack = Hoek.displayStack();
console.log(stack) // returns something like:

[ 'null (/Users/user/Desktop/hoek/test.js:4:18)',
  'Module._compile (module.js:449:26)',
  'Module._extensions..js (module.js:467:10)',
  'Module.load (module.js:356:32)',
  'Module._load (module.js:312:12)',
  'Module.runMain (module.js:492:10)',
  'startup.processNextTick.process._tickCallback (node.js:244:9)' ]

callStack(slice)

Returns a trace stack array.


var stack = Hoek.callStack();
console.log(stack)  // returns something like:

[ [ '/Users/user/Desktop/hoek/test.js', 4, 18, null, false ],
  [ 'module.js', 449, 26, 'Module._compile', false ],
  [ 'module.js', 467, 10, 'Module._extensions..js', false ],
  [ 'module.js', 356, 32, 'Module.load', false ],
  [ 'module.js', 312, 12, 'Module._load', false ],
  [ 'module.js', 492, 10, 'Module.runMain', false ],
  [ 'node.js',
    244,
    9,
    'startup.processNextTick.process._tickCallback',
    false ] ]

Load Files

loadPackage(dir)

Load and parse package.json process root or given directory


var pack = Hoek.loadPackage();  // pack.name === 'hoek'

loadDirModules(path, excludeFiles, target)

Loads modules from a given path; option to exclude files (array).

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