osm-rune-extractor.go

package main

import (
	"encoding/json"
	"fmt"
	"github.com/paulmach/go.geo"
	"github.com/qedus/osmpbf"
	"io"
	"log"
	"os"
	"runtime"
	"strconv"
)

func main() {

	const quadKeyLevel = 6

	d := osmpbf.NewDecoder(os.Stdin)
	err := d.Start(runtime.GOMAXPROCS(-1))
	if err != nil {
		log.Fatal(err)
	}

	charMap := make(map[string]map[string]int)

	for {
		if v, err := d.Decode(); err == io.EOF {
			break
		} else if err != nil {
			log.Fatal(err)
		} else {
			switch v := v.(type) {
			case *osmpbf.Node:
				nameTag, ok := v.Tags["name"]
				if ok == true {
					for _, runeValue := range nameTag {
						quadkey := geo.NewPoint(v.Lon, v.Lat).QuadkeyString(quadKeyLevel)
						mm, ok := charMap[quadkey]
						if !ok {
							mm = make(map[string]int)
							charMap[quadkey] = mm
						}
						charMap[quadkey][strconv.Itoa(int(runeValue))]++
					}
				}
			}
		}
	}

	b, err := json.Marshal(charMap)
	if err != nil {
		fmt.Println("error:", err)
	}
	os.Stdout.Write(b)
}