Experimental aggregation dimensions

This is not meant por public consumption (exposing SQL expressions is undesiderable)

lib/cartodb/models/aggregation/aggregation-query.js

@@ -7,6 +7,7 @@
  * - sourceQuery
  * - res
  * - columns
+ * - dimensions
  */
 const templateForOptions = (options) => {
     let templateFn = aggregationQueryTemplates[options.placement];
@@ -23,11 +24,13 @@ const templateForOptions = (options) => {
  *   aggregation cell is resolution*resolution pixels, where tiles are always 256x256 pixels
  * - columns
  * - placement
+ * - dimensions
  */
 const queryForOptions = (options) => templateForOptions(options)({
     sourceQuery: options.query,
     res: 256/options.resolution,
-    columns: options.columns
+    columns: options.columns,
+    dimensions: options.dimensions
 });
 
 module.exports = queryForOptions;
@@ -53,6 +56,11 @@ const SUPPORTED_AGGREGATE_FUNCTIONS = {
     }
 };
 
+const sep = (list) => {
+    let expr = list.join(', ');
+    return expr ? ', ' + expr : expr;
+};
+
 const aggregateColumns = ctx => {
     return Object.assign({
         _cdb_feature_count: {
@@ -63,12 +71,12 @@ const aggregateColumns = ctx => {
 
 const aggregateColumnNames = ctx => {
     let columns = aggregateColumns(ctx);
-    return Object.keys(columns).join(', ');
+    return sep(Object.keys(columns));
 };
 
 const aggregateColumnDefs = ctx => {
     let columns = aggregateColumns(ctx);
-    return Object.keys(columns).map(column_name => {
+    return sep(Object.keys(columns).map(column_name => {
         const aggregate_function = columns[column_name].aggregate_function || 'count';
         const aggregate_definition = SUPPORTED_AGGREGATE_FUNCTIONS[aggregate_function];
         if (!aggregate_definition) {
@@ -76,10 +84,24 @@ const aggregateColumnDefs = ctx => {
         }
         const aggregate_expression = aggregate_definition.sql(column_name, columns[column_name]);
         return `${aggregate_expression} AS ${column_name}`;
-    }).join(', ');
+    }));
 };
 
 
+const aggregateDimensions = ctx => ctx.dimensions || {};
+
+const dimensionNames = ctx => {
+    return sep(Object.keys(aggregateDimensions(ctx)));
+};
+
+const dimensionDefs = ctx => {
+    let dimensions = aggregateDimensions(ctx);
+    return sep(Object.keys(dimensions).map(dimension_name => {
+        const expression = dimensions[dimension_name];
+        return `${expression} AS ${dimension_name}`;
+    }));
+};
+
 // SQL expression to compute the aggregation resolution (grid cell size).
 // This is equivalent to `${256/ctx.res}*CDB_XYZ_Resolution(CDB_ZoomFromScale(!scale_denominator!))`
 // This is defined by the ctx.res parameter, which is the number of grid cells per tile linear dimension
@@ -106,13 +128,15 @@ const aggregationQueryTemplates = {
                     AVG(ST_X(_cdb_query.the_geom_webmercator)),
                     AVG(ST_Y(_cdb_query.the_geom_webmercator))
                 ), 3857
-            ) AS the_geom_webmercator,
+            ) AS the_geom_webmercator
+            ${dimensionDefs(ctx)}
             ${aggregateColumnDefs(ctx)}
         FROM (${ctx.sourceQuery}) _cdb_query, _cdb_params
         WHERE _cdb_query.the_geom_webmercator && _cdb_params.bbox
         GROUP BY
             Floor(ST_X(_cdb_query.the_geom_webmercator)/_cdb_params.res),
             Floor(ST_Y(_cdb_query.the_geom_webmercator)/_cdb_params.res)
+            ${dimensionNames(ctx)}
     `,
 
     'point-grid': ctx => `
@@ -124,14 +148,16 @@ const aggregationQueryTemplates = {
     _cdb_clusters AS (
         SELECT
         Floor(ST_X(_cdb_query.the_geom_webmercator)/_cdb_params.res)::int AS _cdb_gx,
-        Floor(ST_Y(_cdb_query.the_geom_webmercator)/_cdb_params.res)::int AS _cdb_gy,
+        Floor(ST_Y(_cdb_query.the_geom_webmercator)/_cdb_params.res)::int AS _cdb_gy
+        ${dimensionDefs(ctx)}
         ${aggregateColumnDefs(ctx)}
-        FROM (${ctx.sourceQuery}) _cdb_query, _cdb_params
+        FROM (${ctx.sourceQuery(ctx)}) _cdb_query, _cdb_params
         WHERE the_geom_webmercator && _cdb_params.bbox
-        GROUP BY _cdb_gx, _cdb_gy
+        GROUP BY _cdb_gx, _cdb_gy ${dimensionNames}
     )
     SELECT
-        ST_SetSRID(ST_MakePoint(_cdb_gx*(res+0.5), _cdb_gy*(res+0.5)), 3857) AS the_geom_webmercator,
+        ST_SetSRID(ST_MakePoint(_cdb_gx*(res+0.5), _cdb_gy*(res+0.5)), 3857) AS the_geom_webmercator
+        ${dimensionNames(ctx)}
         ${aggregateColumnNames(ctx)}
         FROM _cdb_clusters, _cdb_params
     `,
@@ -143,19 +169,22 @@ const aggregationQueryTemplates = {
             !bbox! AS bbox
         ), _cdb_clusters AS (
             SELECT
-                MIN(cartodb_id) AS cartodb_id,
+                MIN(cartodb_id) AS cartodb_id
+                ${dimensionDefs(ctx)}
                 ${aggregateColumnDefs(ctx)}
-            FROM (${ctx.sourceQuery}) _cdb_query, _cdb_params
+            FROM (${ctx.sourceQuery(ctx)}) _cdb_query, _cdb_params
             WHERE _cdb_query.the_geom_webmercator && _cdb_params.bbox
             GROUP BY
                 Floor(ST_X(_cdb_query.the_geom_webmercator)/_cdb_params.res),
                 Floor(ST_Y(_cdb_query.the_geom_webmercator)/_cdb_params.res)
+                ${dimensionNames(ctx)}
         ) SELECT
             _cdb_clusters.cartodb_id,
-            the_geom, the_geom_webmercator,
+            the_geom, the_geom_webmercator
+            ${dimensionNames(ctx)}
             ${aggregateColumnNames(ctx)}
         FROM
-            _cdb_clusters INNER JOIN (${ctx.sourceQuery}) _cdb_query
+            _cdb_clusters INNER JOIN (${ctx.sourceQuery(ctx)}) _cdb_query
             ON (_cdb_clusters.cartodb_id = _cdb_query.cartodb_id)
     `
 };

lib/cartodb/models/aggregation/aggregation.js

@@ -9,7 +9,8 @@ module.exports = class Aggregation {
         resolution = 1,
         threshold = Aggregation.THRESHOLD,
         placement = 'centroid',
-        columns = {}
+        columns = {},
+        dimensions = {}
     } = {}) {
         this.mapconfig = mapconfig;
         this.query = query;
@@ -17,6 +18,7 @@ module.exports = class Aggregation {
         this.threshold = threshold;
         this.placement = placement;
         this.columns = columns;
+        this.dimensions = dimensions;
     }
     sql () {
         return aggregationQuery(this);