Implement template method pattern to format histogram query output

lib/cartodb/models/dataview/histograms/base-histogram.js

@@ -41,6 +41,12 @@ module.exports = class BaseHistogram extends BaseDataview {
         return this._buildQuery(psql, override, callback);
     }
 
+    format (result, override) {
+        const histogram = this._getSummary(result, override);
+        histogram.bins = this._getBuckets(result);
+        return histogram;
+    }
+
     getType () {
         return TYPE;
     }
@@ -53,25 +59,21 @@ module.exports = class BaseHistogram extends BaseDataview {
         });
     }
 
-    _getBinEnd (override) {
+    _getBinStart (override) {
+        if (override.hasOwnProperty('start') && override.hasOwnProperty('end')) {
+            return Math.min(override.start, override.end);
+        }
+        return override.start || 0;
+    }
+
+    _getBinEnd (override = {}) {
         if (override.hasOwnProperty('start') && override.hasOwnProperty('end')) {
             return Math.max(override.start, override.end);
         }
         return override.end || 0;
     }
 
-    _getBinsCount (override) {
+    _getBinsCount (override = {}) {
         return override.bins || 0;
     }
-
-    _getWidth (override) {
-        let width = 0;
-        const binsCount = override.bins;
-
-        if (binsCount && Number.isFinite(override.start) && Number.isFinite(override.end)) {
-            width = (override.end - override.start) / binsCount;
-        }
-
-        return width;
-    }
 };

lib/cartodb/models/dataview/histograms/date-histogram.js

@@ -259,90 +259,37 @@ module.exports = class DateHistogram extends BaseHistogram {
         });
     }
 
-    format (result, override) {
-        override = override || {};
-        let buckets = [];
-
-        let binsCount = this._getBinsCount(override);
-        let width = this._getWidth(override);
-        let binsStart = this._getBinStart(override);
-        let nulls = 0;
-        let infinities = 0;
-        let nans = 0;
-        let avg;
-        let timestampStart;
-        let aggregation;
-        let offset;
-
-        if (result.rows.length) {
-            const firstRow = result.rows[0];
-            binsCount = firstRow.bins_number;
-            width = firstRow.bin_width || width;
-            avg = firstRow.avg_val;
-            nulls = firstRow.nulls_count;
-            timestampStart = firstRow.timestamp_start;
-            infinities = firstRow.infinities_count;
-            nans = firstRow.nans_count;
-            binsStart = this._populateBinStart(override, firstRow);
-
-            aggregation = this._getAggregation(override);
-            offset = this._getOffset(override);
-
-            buckets = result.rows.map(row => {
-                const { bin, min, max, avg, freq, timestamp } = row;
-                return { bin, min, max, avg, freq, timestamp };
-            });
-        }
+    _getSummary (result, override) {
+        const firstRow = result.rows[0] || {};
 
         return {
-            aggregation: aggregation,
-            offset: offset,
-            timestamp_start: timestampStart,
-            bin_width: width,
-            bins_count: binsCount,
-            bins_start: binsStart,
-            nulls: nulls,
-            infinities: infinities,
-            nans: nans,
-            avg: avg,
-            bins: buckets
+            aggregation: this._getAggregation(override),
+            offset: this._getOffset(override),
+            timestamp_start: firstRow.timestamp_start,
+
+            bin_width: firstRow.bin_width,
+            bins_count: firstRow.bins_number,
+            bins_start: firstRow.timestamp,
+            nulls: firstRow.nulls_count,
+            infinities: firstRow.infinities_count,
+            nans: firstRow.nans_count,
+            avg: firstRow.avg_val
         };
     }
 
-    _getAggregation (override) {
+    _getBuckets (result) {
+        return result.rows.map(row => {
+            const { bin, min, max, avg, freq, timestamp } = row;
+            return { bin, min, max, avg, freq, timestamp };
+        });
+    }
+
+    _getAggregation (override = {}) {
         return override && override.aggregation ? override.aggregation : this.aggregation;
     }
 
-    _getOffset (override) {
-        if (override && override.offset) {
-            return override.offset;
-        }
-        if (this.offset) {
-            return this.offset;
-        }
-
-        return 0;
-    }
-
-    _getBinStart (override) {
-        if (override.hasOwnProperty('start') && override.hasOwnProperty('end')) {
-            return Math.min(override.start, override.end);
-        }
-        return override.start || 0;
-    }
-
-    _populateBinStart (override, firstRow) {
-        let binStart;
-
-        if (firstRow.hasOwnProperty('timestamp')) {
-            binStart = firstRow.timestamp;
-        } else if (override.hasOwnProperty('start')) {
-            binStart = this._getBinStart(override);
-        } else {
-            binStart = firstRow.min;
-        }
-
-        return binStart;
+    _getOffset (override = {}) {
+        return override.offset || this.offset || 0;
     }
 
     _parseOffset (offset, aggregation) {

lib/cartodb/models/dataview/histograms/numeric-histogram.js

@@ -182,14 +182,14 @@ module.exports = class NumericHistogram extends BaseHistogram {
     _buildQueryTpl (ctx) {
         return `
             WITH
-                ${filteredQueryTpl(ctx)},
-                ${this._shouldOverride(ctx._override) ? overrideBasicsQueryTpl(ctx) : basicsQueryTpl(ctx)},
-                ${this._shouldOverrideRange(ctx._override) || this._shouldOverrideBins(ctx._override) ?
-                    overrideBinsQueryTpl(ctx) :
-                    `${iqrQueryTpl(ctx)}, ${binsQueryTpl(ctx)}`
-                },
-                ${nullsQueryTpl(ctx)}
-                ${ctx._isFloatColumn ? `,${infinitiesQueryTpl(ctx)}, ${nansQueryTpl(ctx)}` : ''}
+            ${filteredQueryTpl(ctx)},
+            ${this._shouldOverride(ctx._override) ? overrideBasicsQueryTpl(ctx) : basicsQueryTpl(ctx)},
+            ${this._shouldOverrideRange(ctx._override) || this._shouldOverrideBins(ctx._override) ?
+                overrideBinsQueryTpl(ctx) :
+                `${iqrQueryTpl(ctx)}, ${binsQueryTpl(ctx)}`
+            },
+            ${nullsQueryTpl(ctx)}
+            ${ctx._isFloatColumn ? `,${infinitiesQueryTpl(ctx)}, ${nansQueryTpl(ctx)}` : ''}
             ${histogramQueryTpl(ctx)}
         `;
     }
@@ -206,54 +206,28 @@ module.exports = class NumericHistogram extends BaseHistogram {
         return override && override.hasOwnProperty('bins');
     }
 
-    format (result, override) {
-        override = override || {};
-        let buckets = [];
-
-        let binsCount = this._getBinsCount(override);
-        let width = this._getWidth(override);
-        let binsStart = this._getBinStart(override);
-        let nulls = 0;
-        let infinities = 0;
-        let nans = 0;
-        let avg;
-
-        if (result.rows.length) {
-            const firstRow = result.rows[0];
-            binsCount = firstRow.bins_number;
-            width = firstRow.bin_width || width;
-            avg = firstRow.avg_val;
-            nulls = firstRow.nulls_count;
-            infinities = firstRow.infinities_count;
-            nans = firstRow.nans_count;
-            binsStart = this._populateBinStart(override, firstRow);
-
-            buckets = result.rows.map(row => {
-                const { bin, min, max, avg, freq } = row;
-                return { bin, min, max, avg, freq };
-            });
-        }
+    _getSummary (result, override) {
+        const firstRow = result.rows[0] || {};
 
         return {
-            bin_width: width,
-            bins_count: binsCount,
-            bins_start: binsStart,
-            nulls: nulls,
-            infinities: infinities,
-            nans: nans,
-            avg: avg,
-            bins: buckets
+            bin_width: firstRow.bin_width,
+            bins_count: firstRow.bins_number,
+            bins_start: this._populateBinStart(firstRow, override),
+            nulls: firstRow.nulls_count,
+            infinities: firstRow.infinities_count,
+            nans: firstRow.nans_count,
+            avg: firstRow.avg_val,
         };
     }
 
-    _getBinStart (override) {
-        if (override.hasOwnProperty('start') && override.hasOwnProperty('end')) {
-            return Math.min(override.start, override.end);
-        }
-        return override.start || 0;
+    _getBuckets (result) {
+        return result.rows.map(row => {
+            const { bin, min, max, avg, freq } = row;
+            return { bin, min, max, avg, freq };
+        });
     }
 
-    _populateBinStart (override, firstRow) {
+    _populateBinStart (firstRow, override = {}) {
         let binStart;
 
         if (override.hasOwnProperty('start')) {