Add field statistics

Author: anttiai

README.md

@@ -209,7 +209,7 @@ Use the following function to get more or less facets.
 client.setNumberOfFacets(20);
 ```
 
-#### Numeric range facets
+#### Numerical range facets
 Group numerical custom fields into range buckets.
 ```js
 // Define ranges. E.g. products with price $0-$100, $100-$200, and over $200 (from value is inclusive, to value is exclusive)
@@ -223,6 +223,14 @@ var ranges = [
 client.addRangeFacet('custom_fields.price', ranges);
 ```
 
+### Field statistics
+Get the minimum, maximum, and average values of a numerical or date-based custom field. The information
+is handy for applications like range filtering.
+```js
+// Search response will have fieldStats element with information like {min: 1230, max: 1590, avg: 1382}
+client.addStatsField('custom_fields.price');
+```
+
 ### Search analytics
 #### Send search event to analytics
 When search is executed, send the event to your AddSearch Analytics Dashboard.

src/apifetch.js

@@ -101,6 +101,14 @@ var executeApiFetch = function(sitekey, type, settings, cb, fuzzyRetry) {
       }
 
 
+      // Stats fields
+      if (settings.statsFields) {
+        for (var i = 0; i<settings.statsFields.length; i++) {
+          qs = qs + '&fieldStat=' + settings.statsFields[i];
+        }
+      }
+
+
       // Personalization events
       if (settings.personalizationEvents && Array.isArray(settings.personalizationEvents)) {
         for (var i = 0; i<settings.personalizationEvents.length; i++) {

src/index.js

@@ -110,6 +110,7 @@ var client = function(sitekey) {
   this.setAutocompleteSize = function(size) { this.settings.setAutocompleteSize(size); }
   this.addFacetField = function(fieldName) { this.settings.addFacetField(fieldName); }
   this.addRangeFacet = function(field, ranges) { this.settings.addRangeFacet(field, ranges); }
+  this.addStatsField = function(field) { this.settings.addStatsField(field); }
   this.setNumberOfFacets = function(numFacets) { this.settings.setNumberOfFacets(numFacets); }
   this.setResultType = function(type) { this.settings.setResultType(type); }
   this.setPersonalizationEvents = function(events) { this.settings.setPersonalizationEvents(events); }

src/settings.js

@@ -154,6 +154,15 @@ var settings = function() {
     });
   }
 
+  this.addStatsField = function(field) {
+    if (!this.settings.statsFields) {
+      this.settings.statsFields = [];
+    }
+    if (this.settings.statsFields.indexOf(field) === -1) {
+      this.settings.statsFields.push(field);
+    }
+  }
+
   this.setNumberOfFacets = function(numFacets) {
     this.settings.numFacets = numFacets;
   }