timeftm

Date[F DateFormat]

A fully comparable date object that always formats to the specified format. Meant to be used for encoding when time is irrelevant.

Example

package main

import (
	"encoding/json"
	"fmt"
	"time"

	"github.com/FallenTaters/timefmt"
	"github.com/FallenTaters/timefmt/formats/iso8601"
	"github.com/FallenTaters/timefmt/formats/rfc3339"
)

type customFormat struct{}

func (customFormat) TimeFormat() string {
	return `2006/01/02 03:04 PM`
}

func (customFormat) DateFormat() string {
	return `02 Jan 2006`
}

type Payload struct {
	Date timefmt.Date[customFormat] `json:"date"`
	Time timefmt.Time[customFormat] `json:"time"`
}

func main() {
	d := timefmt.NewDate[customFormat](2022, 7, 4)
	fmt.Println(d) // 04 Jul 2022

	t := timefmt.TimeFrom[customFormat](time.Date(2022, 7, 4, 16, 19, 59, 1_000_000_000, time.UTC))
	fmt.Println(t) // 2022/07/04 04:20 PM

	// json
	jsonText := `{"date":"04 Jul 2022","time":"2022/07/04 04:20 PM"}`
	var p Payload
	err := json.Unmarshal([]byte(jsonText), &p)
	if err != nil {
		panic(err)
	}

	data, err := json.Marshal(p)
	if err != nil {
		panic(err)
	}
	fmt.Println(string(data) == jsonText) // true

	// dates of different times are comparable
	d1 := time.Date(2022, 7, 4, 0, 0, 0, 0, time.UTC)
	d2 := d1.Add(time.Hour + time.Minute + time.Second)
	fmt.Println(timefmt.DateFrom[customFormat](d1) == timefmt.DateFrom[customFormat](d2)) // true
}

// Some useful formats are predefined
type predefined struct {
	ISO8601      iso8601.Date                       // YYYY-MM-DD
	DayMonthYear timefmt.Date[timefmt.DayMonthYear] // DD/MM/YYYY
	MonthDayYear timefmt.Date[timefmt.MonthDayYear] // MM/DD/YYYY

	RFC3339          rfc3339.Time                           // 2006-01-02T15:04:05Z07:00
	YearMonthDayTime timefmt.Time[timefmt.YearMonthDayTime] // YYYY-MM-DD HH:MM:SS
}

Description

• Compatible with

  • encoding/*
    • through encoding.TextUnmarshaler and encoding.TextMarshaler
  • database/sql and database/sql/driver
    • through sql.Scanner and driver.Valuer

• Easy conversion

  • types can be cast to each other to quickly convert between formats

• Dates Comparable

  • hour, minute, second, nanoseconds and timezone are stripped when using DateFrom

• Custom formats

  • some formats predefined, see example above
  • easy to define new format struct