Aggregation query models: bootstrap hierarchy classes

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

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+module.exports = class BaseAggregation {
+    sql () {
+        throw new Error('Unimplemented method');
+    }
+};
+
+module.exports.baseQueryTemplate = ctx => `
+    select ${ctx} blah.., blah, blah...
+`;

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

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+const BaseAggregation = require('./base-aggregation');
+const { baseQueryTemplate } = BaseAggregation;
+
+module.exports = class RasterAggregation extends BaseAggregation {
+    sql (options) {
+        return rasterAggregationQueryTemplate({
+            source_query: options.sql,
+            res: options.resolution,
+            columns: options.columns
+        });
+    }
+};
+
+const rasterAggregationQueryTemplate = ctx => `
+    WITH
+    _cdb_source AS (
+    -- original query
+    ${ctx.source_query}
+    ),
+    _cdb_resolution AS (
+    SELECT ${ctx.res}*CDB_XYZ_Resolution(CDB_ZoomFromScale(!scale_denominator!))
+    AS _cdb_grid_size
+    -- equivalent to:
+    --   ${ctx.res}*!scale_denominator!*0.00028
+    ),
+    _cdb_gridded AS (
+    SELECT
+    Floor(ST_X(_cdb_source.the_geom_webmercator)/_cdb_grid_size)::int AS _cdb_gx,
+    Floor(ST_Y(_cdb_source.the_geom_webmercator)/_cdb_grid_size)::int AS _cdb_gy,
+    count(*) AS _cdb_feature_count
+    FROM _cdb_source, _cdb_resolution
+    GROUP BY _cdb_gx, _cdb_gy
+    ),
+    _cdb_webmercator AS (
+    SELECT
+        row_number() over() AS cartodb_id,
+        _cdb_feature_count,
+        ST_SetSRID(
+        ST_MakePoint(
+            _cdb_gx*_cdb_grid_size + _cdb_grid_size/2,
+            _cdb_gy*_cdb_grid_size + _cdb_grid_size/2
+        ),
+        3857
+        ) AS the_geom_webmercator
+    FROM _cdb_gridded, _cdb_resolution
+    )
+    SELECT
+        cartodb_id,
+        ST_Transform(the_geom_webmercator, 4326) AS the_geom,
+        the_geom_webmercator,
+        _cdb_feature_count
+    FROM _cdb_webmercator
+    ${baseQueryTemplate(ctx)}
+`;

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

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+const BaseAggregation = require('./base-aggregation');
+const { baseQueryTemplate } = BaseAggregation;
+
+module.exports = class VectorAggregation extends BaseAggregation {
+    sql (options) {
+        return vectorAggregationQueryTemplate({
+            source_query: options.sql,
+            res: options.resolution,
+            columns: options.columns
+        });
+    }
+};
+
+const vectorAggregationQueryTemplate = ctx => `
+    WITH
+    _cdb_source AS (
+    -- original query
+    ${ctx.source_query}
+    ),
+    _cdb_resolution AS (
+    SELECT ${ctx.res}*CDB_XYZ_Resolution(CDB_ZoomFromScale(!scale_denominator!))
+    AS _cdb_grid_size
+    -- equivalent to:
+    --   ${ctx.res}*!scale_denominator!*0.00028
+    ),
+    _cdb_gridded AS (
+    SELECT
+    Floor(ST_X(_cdb_source.the_geom_webmercator)/_cdb_grid_size)::int AS _cdb_gx,
+    Floor(ST_Y(_cdb_source.the_geom_webmercator)/_cdb_grid_size)::int AS _cdb_gy,
+    count(*) AS _cdb_feature_count
+    FROM _cdb_source, _cdb_resolution
+    GROUP BY _cdb_gx, _cdb_gy
+    ),
+    _cdb_webmercator AS (
+    SELECT
+        row_number() over() AS cartodb_id,
+        _cdb_feature_count,
+        ST_SetSRID(
+        ST_MakePoint(
+            _cdb_gx*_cdb_grid_size + _cdb_grid_size/2,
+            _cdb_gy*_cdb_grid_size + _cdb_grid_size/2
+        ),
+        3857
+        ) AS the_geom_webmercator
+    FROM _cdb_gridded, _cdb_resolution
+    )
+    SELECT
+    cartodb_id,
+    ST_Transform(the_geom_webmercator, 4326) AS the_geom,
+    the_geom_webmercator,
+    _cdb_feature_count
+    FROM _cdb_webmercator
+    ${baseQueryTemplate(ctx)}
+`;