Capability to search in nested arrays of objects

Author: Zia Ul Rehman

source/Search.js

@@ -1,5 +1,6 @@
 // @flow
 import getNestedFieldValue from './getNestedFieldValue';
+import getNestedFieldValues from './getNestedFieldValues';
 
 import { PrefixIndexStrategy } from './IndexStrategy/index';
 import { LowerCaseSanitizer } from './Sanitizer/index';
@@ -157,6 +158,44 @@ export class Search {
     return this._searchIndex.search(tokens, this._documents);
   }
 
+    /**
+   * @param doc
+   * @param fieldValue Value to index
+   * @private
+   */
+  indexDocumentsValue_(doc : Object, uid : string, fieldValue : string) : void {
+    this._initialized = true;
+
+    var indexStrategy = this._indexStrategy;
+    var sanitizer = this._sanitizer;
+    var searchIndex = this._searchIndex;
+    var tokenizer = this._tokenizer;
+    var uidFieldName = this._uidFieldName;
+
+    if (
+      fieldValue != null &&
+      typeof fieldValue !== 'string' &&
+      fieldValue.toString
+    ) {
+      fieldValue = fieldValue.toString();
+    }
+
+    if (typeof fieldValue === 'string') {
+      var fieldTokens = tokenizer.tokenize(sanitizer.sanitize(fieldValue));
+
+      for (var fti = 0, numFieldValues = fieldTokens.length; fti < numFieldValues; fti++) {
+        var fieldToken = fieldTokens[fti];
+        var expandedTokens = indexStrategy.expandToken(fieldToken);
+
+        for (var eti = 0, nummExpandedTokens = expandedTokens.length; eti < nummExpandedTokens; eti++) {
+          var expandedToken = expandedTokens[eti];
+
+          searchIndex.indexDocument(expandedToken, uid, doc);
+        }
+      }
+    }
+  }
+
   /**
    * @param documents
    * @param _searchableFields Array containing property names and paths (lists of property names) to nested values
@@ -182,36 +221,17 @@ export class Search {
       }
 
       for (var sfi = 0, numSearchableFields = _searchableFields.length; sfi < numSearchableFields; sfi++) {
-        var fieldValue;
+        var fieldValue, fieldValues;
         var searchableField = _searchableFields[sfi];
 
         if (searchableField instanceof Array) {
-          fieldValue = getNestedFieldValue(doc, searchableField);
+          fieldValues = getNestedFieldValues(doc, searchableField);
+          for (var i = 0; i < fieldValues.length; i++) {
+            this.indexDocumentsValue_(doc, uid, fieldValues[i]);
+          }
         } else {
           fieldValue = doc[searchableField];
-        }
-
-        if (
-          fieldValue != null &&
-          typeof fieldValue !== 'string' &&
-          fieldValue.toString
-        ) {
-          fieldValue = fieldValue.toString();
-        }
-
-        if (typeof fieldValue === 'string') {
-          var fieldTokens = tokenizer.tokenize(sanitizer.sanitize(fieldValue));
-
-          for (var fti = 0, numFieldValues = fieldTokens.length; fti < numFieldValues; fti++) {
-            var fieldToken = fieldTokens[fti];
-            var expandedTokens = indexStrategy.expandToken(fieldToken);
-
-            for (var eti = 0, nummExpandedTokens = expandedTokens.length; eti < nummExpandedTokens; eti++) {
-              var expandedToken = expandedTokens[eti];
-
-              searchIndex.indexDocument(expandedToken, uid, doc);
-            }
-          }
+          this.indexDocumentsValue_(doc, uid, fieldValue);
         }
       }
     }

source/Search.test.js

@@ -1,7 +1,7 @@
 import { Search } from './Search';
 
 describe('Search', function() {
-  var documentBar, documentBaz, documentFoo, nestedDocumentFoo, search;
+  var documentBar, documentBaz, documentFoo, nestedDocumentFoo, nestedArrayDocumentFoo, search;
 
   var validateSearchResults = function(results, expectedDocuments) {
     expect(results.length).toBe(expectedDocuments.length);
@@ -42,6 +42,15 @@ describe('Search', function() {
         title: 'nested foo'
       }
     }
+    nestedArrayDocumentFoo = {
+      uid: 'foo',
+      title: 'foo',
+      description: 'Is kung foo the same as kung fu?',
+      writers: [
+        { name: 'ABC' },
+        { name: 'xyz' }
+      ]
+    };
   });
 
   it('should throw an error if instantiated without the :uidFieldName parameter', function() {
@@ -115,6 +124,13 @@ describe('Search', function() {
     validateSearchResults(search.search('nested foo'), [nestedDocumentFoo]);
   });
 
+  it('should index nested arrays document properties', function() {
+    search.addIndex(['writers', '[]', 'name']);
+    search.addDocument(nestedArrayDocumentFoo);
+
+    validateSearchResults(search.search('ABC'), [nestedArrayDocumentFoo]);
+  });
+
   it('should gracefully handle broken property path', function() {
     search.addIndex(['nested', 'title', 'not', 'existing']);
     search.addDocument(nestedDocumentFoo);

source/getNestedFieldValues.js

@@ -0,0 +1,30 @@
+/**
+ * Find and return nested object values.
+ *
+ * @param object to crawl
+ * @param path Property path
+ * @returns {any}
+ */
+export default function getNestedFieldValues(object : Object, path : Array<string>) {
+  path = path || [];
+  object = object || {};
+
+  var values = [];
+  var value = object;
+  // walk down the property path
+  for (var i = 0; i < path.length; i++) {
+    if (path[i] == "[]") {
+      for (var j=0; j < value.length; j++) {
+        values = values.concat(getNestedFieldValues(value[j], path.slice(i + 1, path.length)));
+      }
+      return values;
+    } else {
+      value = value[path[i]];
+      if (value == null || value == undefined) {
+        return [];
+      }
+    }
+  }
+
+  return [value];
+}