Merge pull request #47 from mapbox/zxystream-use-index

Use map table + map index if present for zxystream

appveyor.yml

@@ -15,6 +15,5 @@ install:
 
 build: OFF
 test: OFF
-test_script: OFF
 deploy: OFF
 

lib/zxystream.js

@@ -28,7 +28,17 @@ function ZXYStream(source, options) {
 
 ZXYStream.prototype._read = function() {
     var stream = this;
-    this.source._db.all('SELECT zoom_level AS z, tile_column AS x, tile_row AS y FROM tiles LIMIT ' + this.batch + ' OFFSET ' + this.offset, function(err, rows) {
+
+    // Check for the existence of a map table that is indexed.
+    if (!stream.table) {
+        return this.source._db.get("select count(1) as count from sqlite_master where type = 'index' and tbl_name = 'map';", function(err, row) {
+            if (err) return stream.emit('error', err);
+            stream.table = row.count === 1 ? 'map' : 'tiles';
+            return stream._read();
+        });
+    }
+
+    this.source._db.all('SELECT zoom_level AS z, tile_column AS x, tile_row AS y FROM ' + this.table + ' LIMIT ' + this.batch + ' OFFSET ' + this.offset, function(err, rows) {
         if (err && err.code === 'SQLITE_ERROR' && /no such table/.test(err.message)) return stream.push(null);
         if (err) return stream.emit('error', err);
         if (!rows.length) return stream.push(null);

test/zxystream.js

@@ -20,6 +20,7 @@ tape('zxystream default batch', function(assert) {
     assert.deepEqual(stream.offset, 0, 'sets stream.offset = 0');
 
     stream.on('data', function(lines) {
+        assert.equal(stream.table, 'map');
         output += lines;
         called++;
     });
@@ -52,6 +53,7 @@ tape('zxystream batch = 10', function(assert) {
     assert.deepEqual(stream.offset, 0, 'sets stream.offset = 0');
 
     stream.on('data', function(lines) {
+        assert.equal(stream.table, 'map');
         output += lines;
         called++;
     });
@@ -73,6 +75,48 @@ tape('zxystream batch = 10', function(assert) {
     });
 });
 
+tape('zxystream unindexed', function(assert) {
+    new MBTiles(__dirname + '/fixtures/unindexed.mbtiles', function(err, s) {
+        assert.ifError(err);
+        source = s;
+        assert.end();
+    });
+});
+
+tape('zxystream unindexed zxystream', function(assert) {
+    var stream = source.createZXYStream();
+    var output = '';
+    var called = 0;
+
+    assert.deepEqual(stream.source, source, 'sets stream.source');
+    assert.deepEqual(stream.batch, 1000, 'sets stream.batch = 1000');
+    assert.deepEqual(stream.offset, 0, 'sets stream.offset = 0');
+
+    stream.on('data', function(lines) {
+        assert.equal(stream.table, 'tiles');
+        output += lines;
+        called++;
+    });
+    stream.on('end', function() {
+        var queue = output.toString().split('\n');
+        assert.equal(queue.length, 286);
+        assert.equal(called, 1, 'emitted data x27 times');
+        checkTile(queue);
+        function checkTile(queue) {
+            if (!queue.length) return assert.end();
+            var zxy = queue.shift();
+            if (!zxy) return checkTile(queue);
+            zxy = zxy.split('/');
+            source.getTile(zxy[0], zxy[1], zxy[2], function(err, buffer, headers) {
+                assert.equal(!err && (buffer instanceof Buffer), true, zxy.join('/') + ' exists');
+                checkTile(queue);
+            });
+        }
+    });
+});
+
+
+
 tape('zxystream empty', function(assert) {
     new MBTiles(__dirname + '/fixtures/non_existent.mbtiles', function(err, s) {
         assert.ifError(err);