utils

A collection of utilities that are used by brick-city packages.

Table of Contents

• Installation
• Usage
• Support
• Contributing
• License

Installation

npm install --save @brick-city/utils

Usage

• arrayToString Nicely format an array for display
• deepfreeze Deep freeze an object and avoid buffers
• isPlainObject Check if an object is a plain object
• isPlainObjectEmpty Check if an object is a plain object, and is empty
• isRegex Check if the passed value is a regular expression
• isUndefinedOrNull Check for an undefined or null value
• mssqlCdcUpdateMaskToBooleanArray Converts an mssql change data capture update mask to an array of boolean
• mssqlCdcUpdateMaskToBitArray Converts an mssql change data capture update mask to an array of bits
• noopLogger A pino structured no-op logger
• traceLogger Generates trace messages, and posts them to the provided logger
• zeroPaddedBinary Nicely format a number as a binary

arrayToString(arr:*[]):string

arrayToString displays an array as you would expect it to look in code. If the element is undefined, only a comma is returned, if it is a string its wrapped in quotes. Simply calls .toString on each element

Throws a type error if passed something other than an array.

import { arrayToString } from '@brick-city/util';

arrayToString([]) // []
arrayToString([,]) // [ ,]
arrayToString([,,]) // [ , ,]
arrayToString([5,,5]) // [ 5, , 5]
arrayToString([1, 'abc', 5]) // [ 1, 'abc', 5]

deepFreeze(obj:Object):Object

deepFreeze takes an object and recursively walks down the object's own properties and deepFreeze(s) any plain objects it finds, and then freezes the object. Buffers and other non-plain objects are skipped. This was a drawback of other "deepFreeze" type functions which are tripped up by Buffers. Returns a reference to the originally passed object.

import { deepFreeze } from '@brick-city/util';

deepFreeze(object)

isPlainObject(obj:any):boolean

isPlainObject returns a boolean that indicates if the object is a plain object.

import { isPlainObject } from '@brick-city/util';

isPlainObject({}) // true
isPlainObject({a:0}) // true
isPlainObject(null) // false
isPlainObject(()=>{}) // false
isPlainObject(7) // false
isPlainObject( new Object() ); //true
isPlainObject( Object.create(null) ); //true

isPlainObjectEmpty(obj:any):boolean

isPlainObjectEmpty returns a boolean that indicates if the object is a plain object and it is empty.

import { isPlainObjectEmpty } from '@brick-city/util';

isPlainObjectEmpty({}) // true
isPlainObjectEmpty({a:0}) // false
isPlainObjectEmpty(null) // false
isPlainObjectEmpty(()=>{}) // false
isPlainObjectEmpty(7) // false
isPlainObjectEmpty( new Object() ); //true
isPlainObjectEmpty( Object.create(null) ); //true

isRegex(obj:any):boolean

isRegex returns a boolean that indicates if the object is a regular expression.

import { isRegex } from '@brick-city/util';

isRegex( new RegExp('') ); //true
isRegex( new RegExp('ab+c') ); //true
isRegex( new RegExp(/.+/ ) ); //true
isRegex({}) // false
isRegex({a:0}) // false
isRegex(null) // false
isRegex(()=>{}) // false
isRegex(7) // false
isRegex( new Object() ); //false
isRegex( Object.create(null) ); //false

isUndefinedOrNull(value:any):boolean

isUndefinedOrNull returns a boolean that indicates if the value passed is either undefined or null.

import { isPlainObjectEmpty } from '@brick-city/util';

isUndefinedOrNull({}) // false
isUndefinedOrNull({a:0}) // false
isUndefinedOrNull(null) // true
isUndefinedOrNull(undefined) // true
isUndefinedOrNull(()=>{}) // false
isUndefinedOrNull(7) // false

mssqlCdcUpdateMaskToBooleanArray(updateMask:Buffer):Array<boolean>

mssqlCdcUpdateMaskToBooleanArray takes a mssql change data capture update mask, and returns a boolean array which signifies which column ordinal bits are set. The first column ordinal in mssql change data capture is 1, so the zeroth array element is empty.

import { mssqlCdcUpdateMaskToBooleanArray:updateMaskToBoolean } from '@brick-city/util';

updateMaskToBoolean(Buffer.from([0b00000010]); // [, false, true, false, false, false, false, false, false]
updateMaskToBoolean(Buffer.from([0b01000000]); // [, false, false, false, false, false, false, true, false]
updateMaskToBoolean(Buffer.from([0b00000001, 0b11111111]); // [, true, true, true, true, true, true, true, true, true, false, false, false, false, false, false, false, true, false, true, false, false, false, false, false ]
updateMaskToBoolean(Buffer.from([0b00000101, 0b00000001, 0b11111111]); // [,
//                                                                          true, true, true, true, true, true, true, true,
//                                                                          true, false, false, false, false, false, false, false,
//                                                                          true, false, true, false, false, false, false, false,
//                                                                      ]
// Notice the bytes are reversed, the last bytes bits appear first

mssqlCdcUpdateMaskToBitArray(updateMask:Buffer):Array<boolean>

mssqlCdcUpdateMaskToBitArray takes a mssql change data capture update mask, and returns a bit array which signifies which column ordinal bits are set. The first column ordinal in mssql change data capture is 1, so the zeroth array element is empty.

import { mssqlCdcUpdateMaskTobitArray:updateMaskToBit } from '@brick-city/util';

updateMaskToBit(Buffer.from([0b00000010]); // [, 0, 1, 0, 0, 0, 0, 0, 0]
updateMaskToBit(Buffer.from([0b01000000]); // [, 0, 0, 0, 0, 0, 0, 1, 0]
updateMaskToBit(Buffer.from([0b00000001, 0b11111111]); // [, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0]
updateMaskToBit(Buffer.from([0b00000101, 0b00000001, 0b11111111]); // [, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0]
// Notice the bytes are reversed, the last bytes bits appear first

noopLogger

noopLogger is an object with all pino logger logging methods defined, but does nothing.

import { noopLogger } from '@brick-city/util';

// Now use it in places where a pino logger is needed, but
// none was passed.

traceLogger(logger:logger):function

Pass a pinot styled logger (needs a 'trace' method, and isLevelEnabled method) to this function and it will return a function that logs a trace message. If the logger does not have a trace method, or the log level is not 'trace', it will return a function that does nothing.

The trace message will include the file name, line number, column number, function name, and method name.

import { traceLogger } from '@brick-city/util';

trace = traceLogger(pinoInstance);

// Now drop these wherever you need to trace the logic

trace()

zeroPaddedBinary(integer:number):string

zeroPaddedBinary returns the integer as a binary string padded with zeros to a length of multiples of 8, and prefixed with '0b'. Throws with a TypeError if the value passed is not a number. The value is rounded down to an integer if it is a float.

import { zeroPaddedBinary } from '@brick-city/util';

zeroPaddedBinary({}) // throws new TypeError('Expecting a number')
zeroPaddedBinary({a:0})  // throws new TypeError('Expecting a number')
zeroPaddedBinary(null)  // throws new TypeError('Expecting a number')
zeroPaddedBinary(undefined)  // throws new TypeError('Expecting a number')
zeroPaddedBinary(262) // '0b0000000100000110'
zeroPaddedBinary(7) // '0b00000111'

Support

Please open an issue for support.

Contributing

Please contribute using Github Flow. Create a branch, add commits, and open a pull request.

License

MIT License