tzot

README

go-tzot

Overview

This repository provides the following program to utilize timezone offset transitions:

• Go package "github.com/Jumpaku/go-tzot".
• CLI tool tzot to generate a slim Go API.

This module is based on the IANA TZ database through a wrapper repository https://github.com/Jumpaku/tz-offset-transitions .

Go package "github.com/Jumpaku/go-tzot"

Installation

go get "github.com/Jumpaku/go-tzot@latest"

Example

package main

import (
	"fmt"
	"github.com/Jumpaku/go-tzot"
)

func main() {
	fmt.Println(tzot.GetTZVersion())
	for _, zoneID := range tzot.AvailableZoneIDs() {
		tzot.GetZone(zoneID) // Got tzot.Zone object
	}
}

Available API

package tzot

import (
	"time"
)

type Zone struct {
	ID          string
	Transitions []Transition
}

type Transition struct {
	When         time.Time
	OffsetBefore time.Duration
	OffsetAfter  time.Duration
}

func GetTZVersion() string

func AvailableZoneIDs() []string

func GetZone(zoneID string) Zone

CLI tool tzot

Installation

Using go install

go install "github.com/Jumpaku/go-tzot@latest"

Using go generate

package main

//go:generate go run "github.com/Jumpaku/go-tzot/cmd/tzot" gen -package=examples -output-path=tzot.go Asia/Tokyo Pacific/Pago_Pago Europe/Zurich Zulu

go generate ./...

Generated API

The generated API is similar to the above but available zone IDs are narrowed to the specified ones with command line arguments to tzot.

Usage

tzot gen

Generates Go code to handle timezone offset transitions for specified timezone IDs.

Usage:
    $ <program> gen [<option>|<argument>]... [-- [<argument>]...]


Options:
    -all[=<boolean>], -a[=<boolean>]  (default=false):
        Generates Go code for all timezone IDs if true.

    -help[=<boolean>], -h[=<boolean>]  (default=false):
        Shows description of this subcommand.

    -output-path=<string>, -o=<string>  (default=""):
        Specifies output path of gen subcommand. If not specified, stdout is used.

    -package=<string>, -p=<string>  (default="tzot_gen"):
        Specifies package that output API belongs to.


Arguments:
    [0:] [<timezone_id_list:string>]...
        specifies timezone IDs for which Go code is generated.

tzot list

Lists all available timezone IDs.

Usage:
    $ <program> list [<option>]...


Options:
    -help[=<boolean>], -h[=<boolean>]  (default=false):
        Shows description of this subcommand.

Documentation

Index

• func AvailableZoneIDs() []string
• func GetTZVersion() string
• func ModuleVersion() string
• type Transition
• type TransitionJSON
• type Zone
  • func GetZone(zoneID string) (zone Zone, found bool)
• type ZoneJSON

Functions

func AvailableZoneIDs

func AvailableZoneIDs() []string

func GetTZVersion

func GetTZVersion() string

func ModuleVersion

func ModuleVersion() string

Types

type Transition

type Transition struct {
	When         time.Time
	OffsetBefore time.Duration
	OffsetAfter  time.Duration
}

type TransitionJSON

type TransitionJSON struct {
	TransitionTimestamp string `json:"transition_timestamp"`
	OffsetSecondsBefore int    `json:"offset_seconds_before"`
	OffsetSecondsAfter  int    `json:"offset_seconds_after"`
}

type Zone

type Zone struct {
	ID          string
	Transitions []Transition
}

func GetZone

func GetZone(zoneID string) (zone Zone, found bool)

type ZoneJSON

type ZoneJSON struct {
	Zone        string           `json:"zone"`
	Transitions []TransitionJSON `json:"transitions"`
}