feat(mapper): return an actual instance of model class

src/dynamo/batchget/batch-get.request.spec.ts

@@ -209,6 +209,7 @@ describe('batch get', () => {
       const result = await request.exec()
       expect(batchGetItemsSpy).toHaveBeenCalled()
       expect(result).toEqual({ [getTableName(SimpleWithPartitionKeyModel)]: [jsItem] })
+      expect(result[getTableName(SimpleWithPartitionKeyModel)][0]).toBeInstanceOf(SimpleWithPartitionKeyModel)
     })
 
     it('execFullResponse', async () => {
@@ -218,6 +219,7 @@ describe('batch get', () => {
         Responses: { [getTableName(SimpleWithPartitionKeyModel)]: [jsItem] },
         UnprocessedKeys: {},
       })
+      expect(result.Responses[getTableName(SimpleWithPartitionKeyModel)][0]).toBeInstanceOf(SimpleWithPartitionKeyModel)
     })
   })
 })

src/dynamo/request/batchgetsingletable/batch-get-single-table.request.spec.ts

@@ -109,10 +109,12 @@ describe('batch get', () => {
       expect(result).toBeDefined()
       expect(result.Items).toBeDefined()
       expect(result.Items).toEqual([jsItem])
+      expect(result.Items[0]).toBeInstanceOf(SimpleWithPartitionKeyModel)
     })
     it('exec', async () => {
       const result = await req.exec()
       expect(result).toEqual([jsItem])
+      expect(result[0]).toBeInstanceOf(SimpleWithPartitionKeyModel)
     })
   })
 

src/dynamo/request/get/get.request.spec.ts

@@ -65,10 +65,14 @@ describe('GetRequest', () => {
       req = new GetRequest(<any>{ getItem: getItemSpy }, SimpleWithPartitionKeyModel, 'my-id')
     })
     it('exec', async () => {
-      expect(await req.exec()).toEqual(jsItem)
+      const res = await req.exec()
+      expect(res).toEqual(jsItem)
+      expect(res).toBeInstanceOf(SimpleWithPartitionKeyModel)
     })
     it('execFullResponse', async () => {
-      expect(await req.execFullResponse()).toEqual({ Item: jsItem })
+      const res = await req.execFullResponse()
+      expect(res).toEqual({ Item: jsItem })
+      expect(res.Item).toBeInstanceOf(SimpleWithPartitionKeyModel)
     })
   })
 

src/dynamo/request/query/query.request.spec.ts

@@ -176,4 +176,10 @@ describe('query request', () => {
       expect(req.params.ScanIndexForward).toBeFalsy()
     })
   })
+
+  // describe('exec', () => {
+  //   it('maps the item', async () => {
+  //
+  //   })
+  // })
 })

src/dynamo/request/transactgetsingletable/transact-get-single-table.request.spec.ts

@@ -48,6 +48,7 @@ describe('TransactGetSingleTableRequest', () => {
         id: 'myId',
         age: 20,
       })
+      expect(resp[0]).toBeInstanceOf(SimpleWithPartitionKeyModel)
     })
 
     it('execNoMap should return the raw value', async () => {
@@ -64,6 +65,7 @@ describe('TransactGetSingleTableRequest', () => {
         id: 'myId',
         age: 20,
       })
+      expect(resp.Items[0]).toBeInstanceOf(SimpleWithPartitionKeyModel)
     })
   })
 

src/dynamo/request/update/update.request.spec.ts

@@ -201,6 +201,22 @@ describe('update request', () => {
     })
   })
 
+  describe('exec', async () => {
+    const updateItemSpy = jasmine.createSpy().and.returnValue(Promise.resolve({
+      Attributes: {
+        id: { S: 'partKey' },
+        creationDate: { S: new Date().toISOString() },
+      },
+    }))
+    const res = await new UpdateRequest(<any>{ updateItem: updateItemSpy }, UpdateModel, 'myId')
+      .updateAttribute('counter').set(25, true)
+      .returnValues('ALL_OLD')
+      .exec()
+
+    expect(res).toBeInstanceOf(UpdateModel)
+
+  })
+
   describe('logger', () => {
     const sampleResponse: DynamoDB.UpdateItemOutput = { Attributes: undefined }
     let logReceiver: jasmine.Spy

src/dynamo/transactget/transact-get.request.spec.ts

@@ -114,10 +114,12 @@ describe('TransactGetRequest', () => {
       const result = await req2.exec()
       expect(Array.isArray(result)).toBeTruthy()
       expect(result.length).toBe(2)
+      expect(result[0]).toBeInstanceOf(SimpleWithPartitionKeyModel)
       expect(result[0]).toEqual({
         id: 'myId',
         age: 20,
       })
+      expect(result[1]).toBeInstanceOf(SimpleWithCompositePartitionKeyModel)
       expect(result[1]).toEqual({
         id: 'myId',
         age: 22,
@@ -130,10 +132,12 @@ describe('TransactGetRequest', () => {
       expect(result).toBeDefined()
       expect(result.ConsumedCapacity).toEqual([])
       expect(result.Items).toBeDefined()
+      expect(result.Items[0]).toBeInstanceOf(SimpleWithPartitionKeyModel)
       expect(result.Items[0]).toEqual({
         id: 'myId',
         age: 20,
       })
+      expect(result.Items[1]).toBeInstanceOf(SimpleWithCompositePartitionKeyModel)
       expect(result.Items[1]).toEqual({
         id: 'myId',
         age: 22,

src/mapper/mapper.spec.ts

@@ -846,6 +846,10 @@ describe('Mapper', () => {
           product = fromDb(productFromDb, Product)
         })
 
+        it('instance', () => {
+          expect(product).toBeInstanceOf(Product)
+        })
+
         it('nested value', () => {
           expect(product.nestedValue).toBeDefined()
           expect(Object.getOwnPropertyNames(product.nestedValue).length).toBe(1)
@@ -862,6 +866,10 @@ describe('Mapper', () => {
           organization = fromDb(organizationFromDb, Organization)
         })
 
+       it('instance', () => {
+         expect(organization).toBeInstanceOf(Organization)
+       })
+
         it('id', () => {
           expect(organization.id).toBe('myId')
         })
@@ -976,6 +984,10 @@ describe('Mapper', () => {
 
         const fromDbVal: ModelWithNonDecoratedEnum = fromDb(attributes, ModelWithNonDecoratedEnum)
 
+        it('instance', () => {
+          expect(fromDbVal).toBeInstanceOf(ModelWithNonDecoratedEnum)
+        })
+
         it('should map all properties', () => {
           expect(fromDbVal).toBeDefined()
 

src/mapper/mapper.ts

@@ -278,7 +278,7 @@ export function fromDb<T>(attributeMap: Attributes<T>, modelConstructor?: ModelC
     }
   })
 
-  return model
+  return modelConstructor ? Object.assign(new modelConstructor(), model) : model
 }
 
 /**