Adds async option for find method - #19

Author: akofman

README.md

@@ -284,7 +284,7 @@ Result:
 }
 ```
 
-If an `id` isn't found, it's simply not returned. Notice that above, there is no object with an `id` of `3`. 
+If an `id` isn't found, it's simply not returned. Notice that above, there is no object with an `id` of `3`.
 
 `find` results are always returned ordered by id. The order of your `ids` array will not necessarily be reflected in the returned array of objects.
 
@@ -321,6 +321,8 @@ The following options based on the options for [PouchDB batch fetch](http://pouc
 * `limit`: Maximum number of documents to return.
 * `skip`: Number of docs to skip before returning (warning: poor performance on IndexedDB/LevelDB!).
 
+Also it is possible to add an async option `{async: true|false}` in order to force to sideload or not dependent objects. Please refer to the [Async relationships](#async-relationships) chapter for more details.
+
 ### db.rel.del(type, object)
 
 Deletes the given object. Returns a Promise.

lib/index.js

@@ -265,7 +265,8 @@ exports.setSchema = function (schema) {
           var relatedType = relationDef[relationType];
           if (typeof relatedType !== 'string') {
             var relationOptions = relatedType.options;
-            if (relationOptions && relationOptions.async) {
+            var async = idOrIds && idOrIds.async;
+            if (async || (relationOptions && relationOptions.async && (async === undefined))) {
               return;
             }
             relatedType = relatedType.type;

test/test.js

@@ -1847,6 +1847,83 @@ function tests(dbName, dbType) {
         });
       });
     });
+
+    it('does sideload if async option is force to false', function () {
+      db.setSchema([
+        {
+          singular: 'author',
+          plural: 'authors',
+          relations: {
+            books: {hasMany: {type: 'books', options: {async: true}}}
+          }
+        },
+        {
+          singular: 'book',
+          plural: 'books',
+          relations: {
+            author: {belongsTo: {type: 'author', options: {async: false}}}
+          }
+        }
+      ]);
+
+      return db.rel.save('author', {
+        name: 'Stephen King',
+        id: 19,
+        books: [1, 2, 3]
+      }).then(function () {
+        return db.rel.save('book', {
+          id: 1,
+          title: 'The Gunslinger'
+        });
+      }).then(function () {
+        return db.rel.save('book', {
+          id: 2,
+          title: 'The Drawing of the Three'
+        });
+      }).then(function () {
+        return db.rel.save('book', {
+          id: 3,
+          title: 'The Wastelands'
+        });
+      }).then(function () {
+        return db.rel.find('author', {async: false});
+      }).then(function (res) {
+        ['authors', 'books'].forEach(function (type) {
+          res[type].forEach(function (obj) {
+            obj.rev.should.be.a('string');
+            delete obj.rev;
+          });
+        });
+        res.should.deep.equal({
+          "authors": [
+            {
+              "name": "Stephen King",
+              "books": [
+                1,
+                2,
+                3
+              ],
+              "id": 19
+            }
+          ],
+          "books": [
+            {
+              "title": "The Gunslinger",
+              "id": 1
+            },
+            {
+              "title": "The Drawing of the Three",
+              "id": 2
+            },
+            {
+              "title": "The Wastelands",
+              "id": 3
+            }
+          ]
+        });
+      });
+    });
+
     it('does not sideload if async option is true', function () {
       db.setSchema([
         {
@@ -1907,6 +1984,66 @@ function tests(dbName, dbType) {
       });
     });
 
+    it('does not sideload if async option is force to true', function () {
+      db.setSchema([
+        {
+          singular: 'author',
+          plural: 'authors',
+          relations: {
+            books: {hasMany: {type: 'books', options: {async: false}}}
+          }
+        },
+        {
+          singular: 'book',
+          plural: 'books',
+          relations: {
+            author: {belongsTo: {type: 'author', options: {async: true}}}
+          }
+        }
+      ]);
+
+      return db.rel.save('author', {
+        name: 'Stephen King',
+        id: 19,
+        books: [1, 2, 3]
+      }).then(function () {
+        return db.rel.save('book', {
+          id: 1,
+          title: 'The Gunslinger'
+        });
+      }).then(function () {
+        return db.rel.save('book', {
+          id: 2,
+          title: 'The Drawing of the Three'
+        });
+      }).then(function () {
+        return db.rel.save('book', {
+          id: 3,
+          title: 'The Wastelands'
+        });
+      }).then(function () {
+        return db.rel.find('author', {async: true});
+      }).then(function (res) {
+        res['authors'].forEach(function (obj) {
+          obj.rev.should.be.a('string');
+          delete obj.rev;
+        });
+        res.should.deep.equal({
+          "authors": [
+            {
+              "name": "Stephen King",
+              "books": [
+                1,
+                2,
+                3
+              ],
+              "id": 19
+            }
+          ]
+        });
+      });
+    });
+
     it('fromRawDoc works with changes', function () {
       db.setSchema([
         {