Use tiletype for detecting content-type headers.

lib/mbtiles.js

@@ -7,6 +7,7 @@ var qs = require('querystring');
 var Buffer = require('buffer').Buffer;
 var sm = new (require('sphericalmercator'));
 var sqlite3 = require('sqlite3');
+var tiletype = require('tiletype');
 
 function noop(err) {
     if (err) throw err;
@@ -150,12 +151,10 @@ MBTiles.prototype.getTile = function(z, x, y, callback) {
         } else if (err) {
             return callback(err);
         } else {
-            var options = {
-                'Content-Type': MBTiles.utils.getMimeType(row.tile_data),
-                'Last-Modified': new Date(mbtiles._stat.mtime).toUTCString(),
-                'ETag': mbtiles._stat.size + '-' + Number(mbtiles._stat.mtime)
-            };
-            return callback(null, row.tile_data, options);
+            var headers = tiletype.headers(tiletype.type(row.tile_data));
+            headers['Last-Modified'] = new Date(mbtiles._stat.mtime).toUTCString();
+            headers['ETag'] = mbtiles._stat.size + '-' + Number(mbtiles._stat.mtime);
+            return callback(null, row.tile_data, headers);
         }
     });
 };

lib/utils.js

@@ -20,21 +20,6 @@ utils.table = function(fields) {
     });
 };
 
-utils.getMimeType = function(data) {
-    if (data[0] === 0x89 && data[1] === 0x50 && data[2] === 0x4E &&
-        data[3] === 0x47 && data[4] === 0x0D && data[5] === 0x0A &&
-        data[6] === 0x1A && data[7] === 0x0A) {
-        return 'image/png';
-    } else if (data[0] === 0xFF && data[1] === 0xD8 &&
-        data[data.length - 2] === 0xFF && data[data.length - 1] === 0xD9) {
-        return 'image/jpeg';
-    } else if (data[0] === 0x47 && data[1] === 0x49 && data[2] === 0x46 &&
-        data[3] === 0x38 && (data[4] === 0x39 || data[4] === 0x37) &&
-        data[5] === 0x61) {
-        return 'image/gif';
-    }
-};
-
 function Queue(callback, concurrency) {
     this.callback = callback;
     this.concurrency = concurrency || 10;

package.json

@@ -23,6 +23,7 @@
         "Konstantin Käfer <kkaefer>"
     ],
     "dependencies": {
+        "tiletype": "0.0.x",
         "sqlite3": "~2.2.0",
         "sphericalmercator": "~1.0.1"
     },