feat(schema): filter plural resource by array of _id -s

src/schema.js

@@ -1,4 +1,4 @@
-import {reduce, each, isDate} from 'lodash';
+import {reduce, each, isDate, isArray} from 'lodash';
 
 import {
   GraphQLObjectType,
@@ -174,9 +174,24 @@ function getSchema (models) {
 
     fields[pluralName] = {
       type: new GraphQLList(type),
+      args: {
+        _id: {
+          name: '_id',
+          type: new GraphQLList(GraphQLString)
+        }
+      },
       resolve: (root, args, source, fieldASTs) => {
         var projections = getProjection(fieldASTs);
-        return modelMap[typeName].find({}, projections);
+        var filter = {};
+
+        // filter by array of _id(s)
+        if (args._id && isArray(args._id)) {
+          filter._id = {
+            $in: args._id
+          };
+        }
+
+        return modelMap[typeName].find(filter, projections);
       }
     };
 

src/schema.spec.js

@@ -124,6 +124,7 @@ describe('schema', () => {
       });
     });
 
+    // TODO: cover sub-documents with unit tests
     it('should get data with sub-document fields');
 
     it('should get data with ref fields', function* () {
@@ -207,6 +208,24 @@ describe('schema', () => {
       });
     });
 
+    it('should filter daya by array of _id(s)', function* () {
+      var findStub = this.sandbox.stub(User, 'find').returnsWithResolve([]);
+
+      var result = yield graphql(schema, `{
+        users(_id: ["aaa", "bbb"]) {
+          name
+        }
+      }`);
+
+      expect(findStub).to.calledWith({
+        _id: {
+          $in: ['aaa', 'bbb']
+        }
+      }, {
+        name: 1
+      })
+    });
+
     // TODO: missing test cases
     it('should filter data by indexed fields');
   });