From fa19f90a6a41042e02c836389df8b07aea40ab02 Mon Sep 17 00:00:00 2001
From: Javier Goizueta <jgoizueta@gmail.com>
Date: Wed, 11 May 2016 18:16:18 +0200
Subject: [PATCH] Apply overviews query rewriter to dataviews

This requires the QueryRewriter to handle a filters parametes in
its data (with Camshaft filter definitions) and a final
options parameters with a bounding_box parameter.
---
 lib/cartodb/backends/dataview.js | 37 ++++++++++++++++++++++++++------
 1 file changed, 30 insertions(+), 7 deletions(-)

diff --git a/lib/cartodb/backends/dataview.js b/lib/cartodb/backends/dataview.js
index 510709c4..946ea0d8 100644
--- a/lib/cartodb/backends/dataview.js
+++ b/lib/cartodb/backends/dataview.js
@@ -9,6 +9,10 @@ var Timer = require('../stats/timer');
 
 var BBoxFilter = require('../models/filter/bbox');
 var DataviewFactory = require('../models/dataview/factory');
+var OverviewsQueryRewriter = require('../utils/overviews_query_rewriter');
+var overviewsQueryRewriter = new OverviewsQueryRewriter({
+    zoom_level: 'CDB_ZoomFromScale(!scale_denominator!)'
+});
 
 function DataviewBackend(analysisBackend) {
     this.analysisBackend = analysisBackend;
@@ -101,12 +105,31 @@ DataviewBackend.prototype.getDataview = function (mapConfigProvider, user, param
             ownFilter = !!ownFilter;
 
             var query;
-            if (ownFilter) {
-                query = node.getQuery();
-            } else {
-                var applyFilters = {};
-                applyFilters[dataviewName] = false;
-                query = node.getQuery(applyFilters);
+
+            var sourceId =  dataviewDefinition.source.id; // node.id
+            var layer = _.find(mapConfig.obj().layers, function(l){ return l.options.source && (l.options.source.id === sourceId); })
+            var queryRewriteData = layer.options.query_rewrite_data;
+            if ( queryRewriteData ) {
+                if ( node.type == 'source' ) {
+                    var filters = node.filters; // TODO: node.getFilters() when available in camshaft
+                    var filters_disabler = _.keys(filters).reduce(function(disabler, filter_id){ disabler[filter_id] = false; return disabler; }, {});
+                    var unfiltered_query = node.getQuery(filters_disabler);
+                    queryRewriteData = _.extend({}, queryRewriteData, { filters: filters });
+                    var rewritten_query = overviewsQueryRewriter.query(unfiltered_query, queryRewriteData, { bounding_box: params.bbox });
+                    if ( rewritten_query !== unfiltered_query ) {
+                        query = rewritten_query;
+                    }
+                }
+            }
+
+            if ( !query ) {
+                if (ownFilter) {
+                    query = node.getQuery();
+                } else {
+                    var applyFilters = {};
+                    applyFilters[dataviewName] = false;
+                    query = node.getQuery(applyFilters);
+                }
             }
 
             if (params.bbox) {
@@ -277,4 +300,4 @@ function dbParamsFromReqParams(params) {
         dbParams.dbname = params.dbname;
     }
     return dbParams;
-}
\ No newline at end of file
+}