common-constants
v4.1.0
Published
A set of constants commonly used across many projects, relating to e.g. date, time, ports, logging, and math
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common-constants
I find myself defining the same constants in project after project. Time to put a stop to that.
Installation
yarn add common-constantsOR
npm add --save common-constantsExports an object literal containing a set of common constants. Categories:
- date and time (constants.datetime)
- math (constants.math)
- default ports for various databases and servers (constants.defaultPorts),
- science (constants.science)
- common log levels and corresponding numeric values (constants.logLevels)
I am forgetful, so it was made to be extremely forgiving, with multiple variants of each constant name allowed. e.g. minInHour, minPerHour, minInHr, minPerHr, minutesPerHour, minutesPerHr, etc.).
Also, it's typescript friendly, because I love you guys.
Why?
Magic numbers are confusing. If you see an algorithm containing the number 60, what are you looking at exactly? Seconds per minute? Minutes per hour? Degrees in one sixth of a circle? Named constants get rid of the problem
Usage example
import { datetime } as DATETIME_CONST from 'common-constants';
console.log(DATETIME_CONST.daysPerMonth.jan); // => 31
console.log(DATETIME_CONST.daysPerCommonYear); // => 365
console.log(DATETIME_CONST.hrPerDay); // => 24Date and time values (constants.datetime)
// Leap year handler(technically not a constant, but it's commonly needed when date constants are required)
isLeap: (year: number | string) => booleanReturns true if the given year is a leap year, false if not
// Microseconds per millisecond
microsecondsPerMillisecond: 1000
microsecondsPerMs: 1000
usPerMs: 1000
usecondsPerMs: 1000
usPerMillisecond: 1000
usecondPerMillisecond: 1000
usecondsPerMillisecond: 1000
μPerMs: 1000
μsPerMs: 1000
μsecondsPerMs: 1000
μPerMillisecond: 1000
μsecondPerMillisecond: 1000
μsPerMillisecond: 1000
μsecondsPerMillisecond: 1000
// Milliseconds per second
msPerSec: 1000
millisecondsPerSecond: 1000
msPerSecond: 1000
msPerSeconds: 1000
millisecondsPerSec: 1000
// Milliseconds per minute
msPerMinute: 60000
millisecondsPerMinute: 60000
msPerMin: 60000
millisecondsPerMin: 60000
// Milliseconds per hour
msPerHour: 3600000
millisecondsPerHour: 3600000
msPerHr: 3600000
millisecondsPerHr: 3600000
// Milliseconds per day
msPerDay: 86400000
millisecondsPerDay: 86400000
// Milliseconds per year (common and leap)
msPerCommonYear: 31536000000
millisecondsPerCommonYear: 31536000000
msPerLeapYear: 31622400000
millisecondsPerLeapYear: 31622400000
// Seconds per minute
secPerMin: 60
secsPerMin: 60
secondsPerMinute: 60
secPerMinute: 60
secsPerMinute: 60
// Seconds per hour
secPerHr: 3600
secsPerHr: 3600
secPerHour: 3600
secsPerHour: 3600
secondsPerHour: 3600
secondsPerHr: 3600
//Seconds per day
secPerDay: 86400
secsPerDay: 86400
secondPerDay: 86400
secondsPerDay: 86400
//Seconds per week
secPerWeek: 604800
secsPerWeek: 604800
secondPerWeek: 604800
secondsPerWeek: 604800
// Seconds per year (common and leap)
secPerCommonYear: 31536000
secondsPerCommonYear: 31536000
secPerLeapYear: 31622400
secondsPerLeapYear: 31622400
// Minutes per hour
minPerHr: 60
minPerHour: 60
minutesPerHour: 60
minutesPerHr: 60
// Minutes per day
minPerDay: 1440
minutesPerDay: 1440
// Minutes per week
minPerWeek: 10080
minutesPerWeek: 10080
// Minutes per year (common and leap)
minPerCommonYear: 525600
minutesPerCommonYear: 525600
minPerLeapYear: 527040
minutesPerLeapYear: 527040
// Hours per day
hrPerDay: 24
hrsPerDay: 24
hoursPerDay: 24
// Hours per week
hrPerWeek: 168
hrsPerWeek: 168
hoursPerWeek: 168
// Hours per year (common and leap)
hrPerCommonYear: 8760
hrsPerCommonYear: 8760
hoursPerCommonYear: 8760
hrPerLeapYear: 8784
hrsPerLeapYear: 8784
hoursPerLeapYear: 8784
// Days per week
daysPerWeek: 7
// Days per year (common and leap)
daysPerCommonYear: 365
daysPerCommonYr: 365
daysPerLeapYear: 366
daysPerLeapYr: 366
daysPerYrAverage: 365.25
daysPerYrMean: 365.25
daysPerYearAverage: 365.25
daysPerYearMean: 365.25
// Weeks per year (common and leap)
weeksPerYear:
full: 52
rem:
common: 1
leap: 2
weeksPerCommonYear: 365 / 7
weeksPerLeapYear: 366 / 7
fullWeeksPerYear: 52
weeksPerYearFloored: 52
weeksPerCommonYearFlooredRemainder: 1
weeksPerLeapYearFlooredRemainder: 2
// Months per year
monthsPerYear: 12
monPerYear: 12
monsPerYear: 12
monPerYr: 12
monsPerYr: 12
monthsPerYr: 12
// Days per month
daysPerMon: daysPerMonth // see 'daysPerMonths' property below
daysPerMonth:
jan: 31
january: 31
feb:
common: 28
leap: 29
february:
common: 28
leap: 29
mar: 31
march: 31
apr: 30
april: 30
may: 31
jun: 30
june: 30
jul: 31
july: 31
aug: 31
august: 31
sep: 30
sept: 30
september: 30
oct: 31
october: 31
nov: 30
november: 30
dec: 31
december: 31
// Unix / epoch start date & time components
epochStartYear: 1970
epochStartMonth: 1
epochStartDate: 1
epochStartHour: 0
epochStartMinute: 0
epochStartSecond: 0
epochStartDateStr: '1970-01-01'
epochStartTimeStr: '00:00:00.000Z'
epochStartDateTimeStr: '1970-01-01T00:00:00.000Z'
unixStartYear: 1970
unixStartMonth: 1
unixStartDate: 1
unixStartHour: 0
unixStartMinute: 0
unixStartSecond: 0
unixStartDateStr: '1970-01-01'
unixStartTimeStr: '00:00:00.000Z'
unixStartDateTimeStr: '1970-01-01T00:00:00.000Z'Math
pi: 3.141592653589
PI: 3.141592653589
π: 3.141592653589
e: 2.718281828459
euler: 2.718281828459
EULER: 2.718281828459
phi: 1.6180339887498
PHI: 1.6180339887498
φ: 1.6180339887498
// Geometry: circle
degreesInCircle: 360
degInCircle: 360
circleDeg: 360
circleDegrees: 360
// Geometry: half-circle
degreesInHalfCircle: 180
degInHalfCircle: 180
halfCircleDeg: 180
halfCircleDegrees: 180
// Geometry: right angle
rightAngleDeg: 90
rightAngleDegrees: 90
rightAngle: 90
// Geometry: sides in a square
sidesInSquare: 4
sidesInASquare: 4
squareSides: 4
numSidesSquare: 4
// Geometry: sides in a triangle
sidesInTriangle: 3
sidesInATriangle: 3
triangleSides: 3
numSidesTriangle: 3Default ports (constants.defaultPorts)
dbPorts: [1025, 1433, 1521, 1522, ..., 6379, 7199, 8983, 9200, 27017, 27018, 50000],
all:
redis: 6379
mongo: 27018
mongodb: 27018
postgres: 5432
postgresql: 5432
pg: 5432
mysql: 3306
express: 3000
expressjs: 3000
expressJS: 3000
expressJs: 3000
http: 80
telnet: 23
smtp: 25
dns: 53
pop3: 110
irc: 194
https: 443
ssh: 22
...etc...Log levels - as numeric values (constants.logLevels)
silly: 1
verbose: 2
debug: 3
info: 4
warn: 5
error: 6
wtf: 7Life, the universe, and everything
lifeTheUniverseAndEverything: 42Science
speedOfLightMetresPerSec: 299792458
speedOfLightMetresPerSecond: 299792458
speedOfLightMPS: 299792458
lightSpeedMetresPerSec: 299792458
lightSpeedMetresPerSecond: 299792458
zeroKelvinInCelsius: -273.15
zeroKInCelsius: -273.15
zeroKelvinInC: -273.15More coming soon.