Fixes WebP detection, resolves #110, #98

CHANGELOG.md

@@ -47,6 +47,8 @@ Most of the updates are demonstrated in `main.go`.
 
 ### General changes
 
+-   Upgraded Docker containers to Go 1.16
+
 ### Command-line interface
 
 -   added support for automatically generating unique tileset IDs using `--generate-ids` option
@@ -87,6 +89,10 @@ Most of the updates are demonstrated in `main.go`.
 -   removed `ServiceSet.AddDBOnPath()`; this is replaced by calling
     `ServiceSet.AddTileset()` for each `Tileset` to register.
 
+### Bug fixes
+
+-   Fixed WebP parsing, now uses simplified check for a `RIFF` header (WebP is only likely RIFF format to be stored in tiles). #98, #110
+
 ## 0.6.1
 
 -   upgraded Docker containers to Go 1.14 (solves out of memory issues during builds on small containers)

mbtiles/mbtiles.go

@@ -373,7 +373,10 @@ func detectTileFormat(data *[]byte) (TileFormat, error) {
 		ZLIB: []byte("\x78\x9c"),
 		PNG:  []byte("\x89\x50\x4E\x47\x0D\x0A\x1A\x0A"),
 		JPG:  []byte("\xFF\xD8\xFF"),
-		WEBP: []byte("\x52\x49\x46\x46\xc0\x00\x00\x00\x57\x45\x42\x50\x56\x50"),
+		// NOTE: this is technically only the RIFF part of the header,
+		// but none of the other RIFF file formats are likely to be stored
+		// as tiles.
+		WEBP: []byte("\x52\x49\x46\x46"),
 	}
 
 	for format, pattern := range patterns {

mbtiles/mbtiles_test.go

@@ -10,8 +10,8 @@ func Test_ListDBs(t *testing.T) {
 	var expected = []string{
 		"testdata/geography-class-jpg.mbtiles",
 		"testdata/geography-class-png.mbtiles",
+		"testdata/geography-class-webp.mbtiles",
 		"testdata/world_cities.mbtiles",
-		"testdata/openstreetmap/open-streets-dc.mbtiles",
 	}
 
 	filenames, err := mbtiles.ListDBs("./testdata")