From 6a7613de6ba52d52b5a696d6e66ebf78ee75807d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Garc=C3=ADa=20Aubert?= <dgaubert@cartodb.com>
Date: Fri, 26 Aug 2016 14:42:22 +0200
Subject: [PATCH] Improved layergroup instantiation to filter non visible
 layers

---
 lib/cartodb/backends/template_maps.js | 41 +++++++++++++++------------
 1 file changed, 23 insertions(+), 18 deletions(-)

diff --git a/lib/cartodb/backends/template_maps.js b/lib/cartodb/backends/template_maps.js
index 9518a334..5ba4a9f3 100644
--- a/lib/cartodb/backends/template_maps.js
+++ b/lib/cartodb/backends/template_maps.js
@@ -473,26 +473,31 @@ o.instance = function(template, params) {
     all_params[k] = val;
   });
 
-  // NOTE: we're deep-cloning the layergroup here
-  var layergroup = JSON.parse(JSON.stringify(template.layergroup));
-  for (var i=0; i<layergroup.layers.length; ++i) {
-    var lyropt = layergroup.layers[i].options;
+    // // NOTE: we're deep-cloning the layergroup here
+    var layergroup = JSON.parse(JSON.stringify(template.layergroup));
 
-    if ( params.styles && params.styles[i] ) {
-        // dynamic styling for this layer
-        lyropt.cartocss = params.styles[i];
-    } else if ( lyropt.cartocss ) {
-        lyropt.cartocss = _replaceVars(lyropt.cartocss, all_params);
-    }
-    if ( lyropt.sql) {
-        lyropt.sql = _replaceVars(lyropt.sql, all_params);
-    }
-    // Anything else ?
-  }
+    layergroup.layers = layergroup.layers
+        .map(function (layer, i) {
+            if (layer.options.visibility === false) {
+                return;
+            }
 
-  layergroup.layers = layergroup.layers.filter(function (layer) {
-      return layer.options.visibility !== false;
-  });
+            if (params.styles && params.styles[i]) {
+                // dynamic styling for this layer
+                layer.options.cartocss = params.styles[i];
+            } else if (layer.options.cartocss) {
+                layer.options.cartocss = _replaceVars(layer.options.cartocss, all_params);
+            }
+
+            if (layer.options.sql) {
+                layer.options.sql = _replaceVars(layer.options.sql, all_params);
+            }
+
+            return layer;
+        })
+        .filter(function (layer) {
+            return !!layer;
+        });
 
   // extra information about the template
   layergroup.template = {