mapserver/server/web/tiles.go
2019-02-08 14:25:07 +01:00

69 lines
1.4 KiB
Go

package web
import (
"image/color"
"mapserver/app"
"mapserver/coords"
"mapserver/tilerenderer"
"net/http"
"strconv"
"strings"
"github.com/prometheus/client_golang/prometheus"
)
var (
tilesCumulativeSize = prometheus.NewCounter(
prometheus.CounterOpts{
Name: "tiles_cumulative_size_served",
Help: "Overall sent bytes of tiles",
},
)
)
type Tiles struct {
ctx *app.App
blank []byte
}
func (t *Tiles) Init() {
t.blank = tilerenderer.CreateBlankTile(color.RGBA{255, 255, 255, 255})
prometheus.MustRegister(tilesCumulativeSize)
}
func (t *Tiles) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
str := strings.TrimPrefix(req.URL.Path, "/api/tile/")
// {layerId}/x/y/zoom
parts := strings.Split(str, "/")
if len(parts) != 4 {
resp.WriteHeader(500)
resp.Write([]byte("wrong number of arguments"))
return
}
layerid, _ := strconv.Atoi(parts[0])
x, _ := strconv.Atoi(parts[1])
y, _ := strconv.Atoi(parts[2])
zoom, _ := strconv.Atoi(parts[3])
c := coords.NewTileCoords(x, y, zoom, layerid)
tile, err := t.ctx.Objectdb.GetTile(c)
if err != nil {
resp.WriteHeader(500)
resp.Write([]byte(err.Error()))
} else {
resp.Header().Add("content-type", "image/png")
if tile == nil {
resp.Write(t.blank)
//TODO: cache/layer color
} else {
tilesCumulativeSize.Add(float64(len(tile.Data)))
resp.Write(tile.Data)
}
}
}