libgo/go/time/genzabbrs.go

   1 // Copyright 2013 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // +build ignore
   6
   7 //
   8 // usage:
   9 //
  10 // go run genzabbrs.go -output zoneinfo_abbrs_windows.go
  11 //
  12
  13 package main
  14
  15 import (
  16         "bytes"
  17         "encoding/xml"
  18         "flag"
  19         "go/format"
  20         "io/ioutil"
  21         "log"
  22         "net/http"
  23         "sort"
  24         "text/template"
  25         "time"
  26 )
  27
  28 var filename = flag.String("output", "zoneinfo_abbrs_windows.go", "output file name")
  29
  30 // getAbbrs finds timezone abbreviations (standard and daylight saving time)
  31 // for location l.
  32 func getAbbrs(l *time.Location) (st, dt string) {
  33         t := time.Date(time.Now().Year(), 0, 1, 0, 0, 0, 0, l)
  34         abbr1, off1 := t.Zone()
  35         for i := 0; i < 12; i++ {
  36                 t = t.AddDate(0, 1, 0)
  37                 abbr2, off2 := t.Zone()
  38                 if abbr1 != abbr2 {
  39                         if off2-off1 < 0 { // southern hemisphere
  40                                 abbr1, abbr2 = abbr2, abbr1
  41                         }
  42                         return abbr1, abbr2
  43                 }
  44         }
  45         return abbr1, abbr1
  46 }
  47
  48 type zone struct {
  49         WinName  string
  50         UnixName string
  51         StTime   string
  52         DSTime   string
  53 }
  54
  55 type zones []*zone
  56
  57 func (zs zones) Len() int           { return len(zs) }
  58 func (zs zones) Swap(i, j int)      { zs[i], zs[j] = zs[j], zs[i] }
  59 func (zs zones) Less(i, j int) bool { return zs[i].UnixName < zs[j].UnixName }
  60
  61 const wzURL = "http://unicode.org/cldr/data/common/supplemental/windowsZones.xml"
  62
  63 type MapZone struct {
  64         Other     string `xml:"other,attr"`
  65         Territory string `xml:"territory,attr"`
  66         Type      string `xml:"type,attr"`
  67 }
  68
  69 type SupplementalData struct {
  70         Zones []MapZone `xml:"windowsZones>mapTimezones>mapZone"`
  71 }
  72
  73 func readWindowsZones() (zones, error) {
  74         r, err := http.Get(wzURL)
  75         if err != nil {
  76                 return nil, err
  77         }
  78         defer r.Body.Close()
  79
  80         data, err := ioutil.ReadAll(r.Body)
  81         if err != nil {
  82                 return nil, err
  83         }
  84
  85         var sd SupplementalData
  86         err = xml.Unmarshal(data, &sd)
  87         if err != nil {
  88                 return nil, err
  89         }
  90         zs := make(zones, 0)
  91         for _, z := range sd.Zones {
  92                 if z.Territory != "001" {
  93                         // to avoid dups. I don't know why.
  94                         continue
  95                 }
  96                 l, err := time.LoadLocation(z.Type)
  97                 if err != nil {
  98                         return nil, err
  99                 }
 100                 st, dt := getAbbrs(l)
 101                 zs = append(zs, &zone{
 102                         WinName:  z.Other,
 103                         UnixName: z.Type,
 104                         StTime:   st,
 105                         DSTime:   dt,
 106                 })
 107         }
 108         return zs, nil
 109 }
 110
 111 func main() {
 112         flag.Parse()
 113         zs, err := readWindowsZones()
 114         if err != nil {
 115                 log.Fatal(err)
 116         }
 117         sort.Sort(zs)
 118         var v = struct {
 119                 URL string
 120                 Zs  zones
 121         }{
 122                 wzURL,
 123                 zs,
 124         }
 125         var buf bytes.Buffer
 126         err = template.Must(template.New("prog").Parse(prog)).Execute(&buf, v)
 127         if err != nil {
 128                 log.Fatal(err)
 129         }
 130         data, err := format.Source(buf.Bytes())
 131         if err != nil {
 132                 log.Fatal(err)
 133         }
 134         err = ioutil.WriteFile(*filename, data, 0644)
 135         if err != nil {
 136                 log.Fatal(err)
 137         }
 138 }
 139
 140 const prog = `
 141 // Copyright 2013 The Go Authors. All rights reserved.
 142 // Use of this source code is governed by a BSD-style
 143 // license that can be found in the LICENSE file.
 144
 145 // Code generated by genzabbrs.go; DO NOT EDIT.
 146 // Based on information from {{.URL}}
 147
 148 package time
 149
 150 type abbr struct {
 151         std string
 152         dst string
 153 }
 154
 155 var abbrs = map[string]abbr{
 156 {{range .Zs}}   "{{.WinName}}": {"{{.StTime}}", "{{.DSTime}}"}, // {{.UnixName}}
 157 {{end}}}
 158
 159 `