SCEPTER-utility-lib
A library of useful javascript utility functions
Usage
Add this library to your project via npm or yarn with the command:
npm install -S @source4society/scepter-utility-lib
or yarn add @source4society/scepter-utility-lib
Then in your code, you can import the utility class:
import SCEPTERUtils from '@source4society/scepter-utility-lib';
or for commonJS
const SCEPTERUtils = require('@source4society/scepter-utility-lib')
Functions
isEmpty / isNotEmpty
use this to determine if a given variable is "empty". "Emptiness" is defined as an undefined value, null, NaN, {}, [], or ''. A value such as boolean false is not counted as empty, nor is a function or a class (instantiated or definition). isNotEmpty is simply the not of isEmpty
getRandomInt
Specify a min (inclusive) and max (exclusive) to get back a random number based on the platform (or injected) Math.random() function between min/max
valueOrDefault
If the value is empty, return default, otherwise return the value. Very useful for avoiding ternary's for better line coverage when setting default values
ssValueOrDefault
Same as above, but the second argument is a function or lambda to be executed if the first argument is empty. SS stands for "short-circuit".
ifTrueElseDefault
If the first argument evaluates to true, return the second argument, otherwise return the third. Very useful for avoiding branching logic but beware - you cannot short circuit the arguments like you can with a normal ternary
ssIfTrueElseDefault
Like above but value1 and value2 should be defined as functions or lambdas to provide short circuiting.
emptyAt / notEmptyAt
Like isEmpty and isNotEmpty but will traverse an objects properties to see if the property chain exists/has an empty value. The first argument is the object, the second argument is an array of subproperties to search in the order of nesting.
ucFirst
Useful utility to transform a word to title case (first letter becomes uppercase). Pass in a string and get back a string
validateApiResult
SCEPTER API results always return with a status: true property when successful, and status: false when something goes wrong. This will attempt to throw the error in the response if status is anything other than true. It will also parse from a string if the given result is in string form.
keyGenerator
Generates a random character string of length length, useful for creating API keys or jwt encoding keys.
getInOrDefault
This is useful for getting values from nester properties within objects, and returning a default value if the property does not exist or is empty. The first argument is the object to search, the second is an array of properties in nesting order, the third is the default value to return if the property does not exist or is empty
immutableToJS
Convert an immutable object to its JS form if the object is not empty, otherwise return undefined. Simply takes the immutableJS object as an argument
standardCallback
Use this to split the results of a standard callback into two separate function calls. The first argument is the error object, the second is the success (data) object. If the error object is not empty, then the error callback is called with the error data, otherwise the success callback is called with the success data
eitherOf
Use this function to disjoin (||) two values
conjunctionOf
Use this function to conjoin (&&) two values
ssEitherOf
Use this function to disjoin (||) two values, but the second argument should be a function that will be executed if the first is not true or undefined
ssConjunctionOf
Use this function to conjoin (&&) two values, but the second argument should be a function that will be executed if the first is not true or undefined
trueIfEqual
Function will return the result of value1 === value2
nullOp
Returns null value, useful if you want to return null in a short circuited function or if you want to render a null React component