General purpose node utilities [](http://travis-ci.org/spumko/hoek) # Table of Contents * [Introduction](#introduction "Introduction") * [Object](#object "Object") * [clone](#cloneobj "clone") * [merge](#mergetarget-source-isnulloverride-ismergearrays "merge") * [applyToDefaults](#applytodefaultsdefaults-options "applyToDefaults") * [unique](#uniquearray-key "unique") * [mapToObject](#maptoobjectarray-key "mapToObject") * [intersect](#intersectarray1-array2 "intersect") * [matchKeys](#matchkeysobj-keys "matchKeys") * [flatten](#flattenarray-target "flatten") * [removeKeys](#removekeysobject-keys "removeKeys") * [reach](#reachobj-chain "reach") * [inheritAsync](#inheritasyncself-obj-keys "inheritAsync") * [rename](#renameobj-from-to "rename") * [Timer](#timer "Timer") * [Binary Encoding/Decoding](#binary "Binary Encoding/Decoding") * [base64urlEncode](#binary64urlEncodevalue "binary64urlEncode") * [base64urlDecode](#binary64urlDecodevalue "binary64urlDecode") * [Escaping Characters](#escaped "Escaping Characters") * [escapeHtml](#escapeHtmlstring "escapeHtml") * [escapeHeaderAttribute](#escapeHeaderAttributeattribute "escapeHeaderAttribute") * [escapeRegex](#escapeRegexstring "escapeRegex") * [Errors](#errors "Errors") * [assert](#assertmessage "assert") * [abort](#abortmessage "abort") * [displayStack](#displayStackslice "displayStack") * [callStack](#callStackslice "callStack") * [toss](#tosscondition "toss") * [Load files](#load-files "Load Files") * [loadPackage](#loadPackagedir "loadpackage") * [loadDirModules](#loadDirModulespath-excludefiles-target "loaddirmodules") # 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: ```javascript 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). ```javascript 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 ```javascript 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 ```javascript 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 ```javascript 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 ```javascript 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 ```javascript var array1 = [1, 2, 3]; var array2 = [1, 4, 5]; var newArray = Hoek.intersect(array1, array2) // results in [1] ``` ### matchKeys(obj, keys) Find which keys are present ```javascript var obj = {a: 1, b: 2, c: 3}; var keys = ["a", "e"]; Hoek.matchKeys(obj, keys) // returns ["a"] ``` ### flatten(array, target) Flatten an array ```javascript var array = [1, 2, 3]; var target = [4, 5]; var flattenedArray = Hoek.flatten(array, target) // results in [4, 5, 1, 2, 3]; ``` ### removeKeys(object, keys) Remove keys ```javascript var object = {a: 1, b: 2, c: 3, d: 4}; var keys = ["a", "b"]; Hoek.removeKeys(object, keys) // object is now {c: 3, d: 4} ``` ### reach(obj, chain) Converts an object key chain string to reference ```javascript var chain = 'a.b.c'; var obj = {a : {b : { c : 1}}}; Hoek.reach(obj, chain) // returns 1 ``` ### inheritAsync(self, obj, keys) Inherits a selected set of methods from an object, wrapping functions in asynchronous syntax and catching errors ```javascript var targetFunc = function () { }; var proto = { a: function () { return 'a!'; }, b: function () { return 'b!'; }, c: function () { throw new Error('c!'); } }; var keys = ['a', 'c']; Hoek.inheritAsync(targetFunc, proto, ['a', 'c']); var target = new targetFunc(); target.a(function(err, result){console.log(result)} // returns 'a!' target.c(function(err, result){console.log(result)} // returns undefined target.b(function(err, result){console.log(result)} // gives error: Object [object Object] has no method 'b' ``` ### rename(obj, from, to) Rename a key of an object ```javascript var obj = {a : 1, b : 2}; Hoek.rename(obj, "a", "c"); // obj is now {c : 1, b : 2} ``` # 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. ```javascript example : var timerObj = new Hoek.Timer(); console.log("Time is now: " + timerObj.ts) console.log("Elapsed time from initialization: " + timerObj.elapsed() + 'milliseconds') ``` # 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: ```javascript internals.htmlEscaped = { '&': '&', '<': '<', '>': '>', '"': '"', "'": ''', '`': '`' }; ``` ### escapeHtml(string) ```javascript var string = ' hey '; var escapedString = Hoek.escapeHtml(string); // returns <html> hey </html> ``` ### escapeHeaderAttribute(attribute) Escape attribute value for use in HTTP header ```javascript var a = Hoek.escapeHeaderAttribute('I said "go w\\o me"'); //returns I said \"go w\\o me\" ``` ### escapeRegex(string) Escape string for Regex construction ```javascript var a = Hoek.escapeRegex('4^f$s.4*5+-_?%=#!:@|~\\/`"(>)[<]d{}s,'); // returns 4\^f\$s\.4\*5\+\-_\?%\=#\!\:@\|~\\\/`"\(>\)\[<\]d\{\}s\, ``` # Errors ### assert(message) ```javascript 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 ```javascript 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. ```javascript 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 ] ] ``` ### toss(condition) toss(condition /*, [message], callback */) Return an error as first argument of a callback # Load Files ### loadPackage(dir) Load and parse package.json process root or given directory ```javascript var pack = Hoek.loadPackage(); // pack.name === 'hoek' ``` ### loadDirModules(path, excludeFiles, target) Loads modules from a given path; option to exclude files (array).