add show specific tile to show [#21]

protomaps · Oct 14, 2022 · 971ddd6 · 971ddd6
1 parent 82c42cd
commit 971ddd6
Showing 1 changed file with 81 additions and 29 deletions.
diff --git a/pmtiles/show.go b/pmtiles/show.go
@@ -1,20 +1,30 @@
 package pmtiles
 
 import (
+	"bytes"
 	"context"
 	"flag"
 	"fmt"
 	"github.com/dustin/go-humanize"
 	"gocloud.dev/blob"
 	"io"
 	"log"
+	"os"
+	"strconv"
 )
 
 func Show(logger *log.Logger, args []string) error {
-	cmd := flag.NewFlagSet("upload", flag.ExitOnError)
+	cmd := flag.NewFlagSet("show", flag.ExitOnError)
 	cmd.Parse(args)
 	bucketURL := cmd.Arg(0)
 	file := cmd.Arg(1)
+	arg_z := cmd.Arg(2)
+	arg_x := cmd.Arg(3)
+	arg_y := cmd.Arg(4)
+
+	if bucketURL == "" || file == "" {
+		return fmt.Errorf("USAGE: show BUCKET_URL KEY")
+	}
 
 	ctx := context.Background()
 	bucket, err := blob.OpenBucket(ctx, bucketURL)
@@ -35,35 +45,77 @@ func Show(logger *log.Logger, args []string) error {
 	r.Close()
 
 	header := deserialize_header(b[0:HEADERV3_LEN_BYTES])
-	var tile_type string
-	switch header.TileType {
-	case Mvt:
-		tile_type = "Vector Protobuf (MVT)"
-	case Png:
-		tile_type = "Raster PNG"
-	case Jpeg:
-		tile_type = "Raster Jpeg"
-	case Webp:
-		tile_type = "Raster WebP"
-	default:
-		tile_type = "Unknown"
-	}
-	fmt.Printf("total size: %s\n", humanize.Bytes(uint64(r.Size())))
-	fmt.Printf("tile type: %s\n", tile_type)
-	fmt.Printf("bounds: %f,%f %f,%f\n", float64(header.MinLonE7)/10000000, float64(header.MinLatE7)/10000000, float64(header.MaxLonE7)/10000000, float64(header.MaxLatE7)/10000000)
-	fmt.Printf("min zoom: %d\n", header.MinZoom)
-	fmt.Printf("max zoom: %d\n", header.MaxZoom)
-	fmt.Printf("center: %f,%f\n", float64(header.CenterLonE7)/10000000, float64(header.CenterLatE7)/10000000)
-	fmt.Printf("center zoom: %d\n", header.CenterZoom)
-	fmt.Printf("addressed tiles count: %d\n", header.AddressedTilesCount)
-	fmt.Printf("tile entries count: %d\n", header.TileEntriesCount)
-	fmt.Printf("tile contents count: %d\n", header.TileContentsCount)
-	fmt.Printf("clustered: %t\n", header.Clustered)
 
-	// entries := deserialize_entries(bytes.NewBuffer(b[header.RootOffset:header.RootOffset+header.RootLength]))
-	// for _, entry := range entries {
-	// 	fmt.Println(entry)
-	// }
+	if arg_z == "" {
+		var tile_type string
+		switch header.TileType {
+		case Mvt:
+			tile_type = "Vector Protobuf (MVT)"
+		case Png:
+			tile_type = "Raster PNG"
+		case Jpeg:
+			tile_type = "Raster Jpeg"
+		case Webp:
+			tile_type = "Raster WebP"
+		default:
+			tile_type = "Unknown"
+		}
+		fmt.Printf("total size: %s\n", humanize.Bytes(uint64(r.Size())))
+		fmt.Printf("tile type: %s\n", tile_type)
+		fmt.Printf("bounds: %f,%f %f,%f\n", float64(header.MinLonE7)/10000000, float64(header.MinLatE7)/10000000, float64(header.MaxLonE7)/10000000, float64(header.MaxLatE7)/10000000)
+		fmt.Printf("min zoom: %d\n", header.MinZoom)
+		fmt.Printf("max zoom: %d\n", header.MaxZoom)
+		fmt.Printf("center: %f,%f\n", float64(header.CenterLonE7)/10000000, float64(header.CenterLatE7)/10000000)
+		fmt.Printf("center zoom: %d\n", header.CenterZoom)
+		fmt.Printf("addressed tiles count: %d\n", header.AddressedTilesCount)
+		fmt.Printf("tile entries count: %d\n", header.TileEntriesCount)
+		fmt.Printf("tile contents count: %d\n", header.TileContentsCount)
+		fmt.Printf("clustered: %t\n", header.Clustered)
+	} else {
+		// write the tile to stdout
 
+		z, _ := strconv.ParseUint(arg_z, 10, 8)
+		x, _ := strconv.ParseUint(arg_x, 10, 32)
+		y, _ := strconv.ParseUint(arg_y, 10, 32)
+		tile_id := ZxyToId(uint8(z), uint32(x), uint32(y))
+
+		dir_offset := header.RootOffset
+		dir_length := header.RootLength
+
+		for depth := 0; depth <= 3; depth++ {
+			r, err := bucket.NewRangeReader(ctx, file, int64(dir_offset), int64(dir_length), nil)
+			if err != nil {
+				return fmt.Errorf("Network error")
+			}
+			defer r.Close()
+			b, err := io.ReadAll(r)
+			if err != nil {
+				return fmt.Errorf("I/O Error")
+			}
+			directory := deserialize_entries(bytes.NewBuffer(b))
+			entry, ok := find_tile(directory, tile_id)
+			if ok {
+				if entry.RunLength > 0 {
+					tile_r, err := bucket.NewRangeReader(ctx, file, int64(header.TileDataOffset+entry.Offset), int64(entry.Length), nil)
+					if err != nil {
+						return fmt.Errorf("Network error")
+					}
+					defer tile_r.Close()
+					tile_b, err := io.ReadAll(tile_r)
+					if err != nil {
+						return fmt.Errorf("I/O Error")
+					}
+					os.Stdout.Write(tile_b)
+					break
+				} else {
+					dir_offset = header.LeafDirectoryOffset + entry.Offset
+					dir_length = uint64(entry.Length)
+				}
+			} else {
+				fmt.Println("Tile not found in archive.")
+				return nil
+			}
+		}
+	}
 	return nil
 }