Change update to partial

README.md

@@ -100,4 +100,33 @@ await getAllItems();
 await myRepo.remove(id);
 ```
 
+## Update
+
+- Requires `dynamodb:UpdateItem`
+- Honors revision check; it will only update if the revision on disk is the one you are updating. Will return a `409` if the revision has changed underneath you.
+- Will perform a partial update if you don't pass in all properties. Think of this as a "patch" vs. a replacement update. The `key` and `revision` properties are always required.
+- Returns the entire entity, including both new and unchanged properties
+
+```js
+const person = await myRepo.create({
+  name: 'Joe',
+  age: 28,
+  favoriteColor: 'blue',
+});
+// Full item update
+person.favoriteColor = 'teal';
+const newPerson1 = await myRepo.update(person);
+console.log(newPerson1.favoriteColor); // 'teal'
+
+// Partial update
+const partial = {
+  favoriteColor: 'aquamarine',
+  key: person.key,
+  revision: newPerson1.revision,
+};
+const newPerson2 = await myRepo.update(partial);
+console.log(newPerson2.favoriteColor); // 'aquamarine'
+console.log(newPerson2.age); // 28
+```
+
 // More Coming Soon...

lib/keyValueRepository.ts

@@ -4,7 +4,6 @@ import {
   DynamoDBDocumentClient,
   GetCommand,
   PutCommand,
-  PutCommandInput,
   ScanCommand,
   ScanCommandInput,
   ScanCommandOutput,
@@ -117,49 +116,7 @@ class KeyValueRepository {
     return itemToSave;
   }
 
-  async update(item: any) {
-    this.validateRequiredProperties(item);
-    const { revision: previousRevision } = item;
-    const itemToSave = setRepositoryModifiedProperties(item);
-    const putParams: PutCommandInput = {
-      TableName: this.tableName,
-      Item: itemToSave,
-      ConditionExpression: 'attribute_exists(#key) AND #revision = :prevRev',
-      ExpressionAttributeNames: {
-        '#key': this.keyName,
-        '#revision': 'revision',
-      },
-      ExpressionAttributeValues: {
-        ':prevRev': previousRevision,
-      },
-      ReturnValuesOnConditionCheckFailure: 'ALL_OLD',
-    };
-    try {
-      await this.docClient.send(new PutCommand(putParams));
-    } catch (err: any) {
-      if (err.name === 'ConditionalCheckFailedException') {
-        const { Item } = err;
-        if (isNotFoundConflict(Item)) {
-          throw NotFound();
-        }
-        if (
-          isRevisionConflict({
-            expectedRevision: previousRevision,
-            actualRevision: Item?.revision?.N,
-          })
-        ) {
-          throw Conflict(
-            `Conflict: Item in DB has revision [${Item?.revision?.N}]. You are using revision [${previousRevision}]`,
-          );
-        }
-      }
-      throw err;
-    }
-
-    return itemToSave;
-  }
-
-  async updatePartial(item: any): Promise<Record<string, any>> {
+  async update(item: any): Promise<Record<string, any>> {
     this.validateRequiredProperties(item);
     const updateInput = this.buildUpdateCommandInput(item);
     let result: UpdateCommandOutput;
@@ -189,7 +146,7 @@ class KeyValueRepository {
 
   private buildUpdateCommandInput(item: any): UpdateCommandInput {
     const { revision: previousRevision } = item;
-    const itemToSave = setRepositoryModifiedPropertiesForPartialUpdate(item);
+    const itemToSave = setRepositoryModifiedPropertiesForUpdate(item);
     const key = createDynamoDbKey({ keyName: this.keyName, keyValue: itemToSave[this.keyName] });
     const updateInput: UpdateCommandInput = {
       TableName: this.tableName,
@@ -230,15 +187,7 @@ const isRevisionConflict = (input: { expectedRevision: number; actualRevision: n
   return expectedRevision !== actualRevision;
 };
 
-const setRepositoryModifiedProperties = (item: any) => {
-  const returnItem = { ...item };
-  returnItem.updatedAt = new Date().toISOString();
-  returnItem.revision = item.revision + 1;
-
-  return returnItem;
-};
-
-const setRepositoryModifiedPropertiesForPartialUpdate = (item: any) => {
+const setRepositoryModifiedPropertiesForUpdate = (item: any) => {
   const returnItem = { ...item };
   delete returnItem.createdAt;
   returnItem.updatedAt = new Date().toISOString();

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@setho/dynamodb-repository",
-  "version": "0.8.7",
+  "version": "0.9.0",
   "description": "DynamoDB repository for hash-key and hash-key/range indexed tables. Designed for Lambda use. Handles nice-to-haves like created and updated timestamps and default id creation.",
   "license": "MIT",
   "repository": "setho/dynamodb-repository",

test/update.int.test.ts

@@ -85,14 +85,32 @@ describe('When updating an item', () => {
     const repo = new KeyValueRepository({ tableName: TableName, keyName: KeyName, documentClient });
     const newField1 = faker.lorem.slug();
 
+    // ACT
+    await repo.update({ ...item, field1: newField1 });
+
+    // ASSERT
+    const itemInDb = await repo.get(key);
+    expect(itemInDb.field1).toEqual(newField1);
+  });
+
+  it('should return the entire object, including unchanged properties', async () => {
+    // ARRANGE
+    const item = createTestKeyValueItem();
+    const key = await insertHashKeyItem(item);
+    testKeys.push(key);
+    const repo = new KeyValueRepository({ tableName: TableName, keyName: KeyName, documentClient });
+    const newField1 = faker.lorem.slug();
+
     // ACT
     const result = await repo.update({ ...item, field1: newField1 });
 
     // ASSERT
+    expect(result.map1).toEqual(item.map1);
+    expect(result.field1).not.toEqual(item.field1);
     expect(result.field1).toEqual(newField1);
   });
 
-  it.skip('should maintain original createdAt value', async () => {
+  it('should maintain original createdAt value', async () => {
     // ARRANGE
     const item = createTestKeyValueItem();
     const originalCreatedAt = item.createdAt;
@@ -158,4 +176,29 @@ describe('When updating an item', () => {
       await expect(updateAction()).rejects.toThrow(`${item.revision}`);
     });
   });
+
+  describe('with a subset of properties', () => {
+    it('should return the entire object with the updated properties', async () => {
+      // ARRANGE
+      const item = createTestKeyValueItem();
+      const key = await insertHashKeyItem(item);
+      testKeys.push(key);
+      const itemWithoutField1: any = { ...item };
+      delete itemWithoutField1.field1;
+      const newMap = { field2: 'affirmative' };
+      itemWithoutField1.map1 = newMap;
+      const repo = new KeyValueRepository({
+        tableName: TableName,
+        keyName: KeyName,
+        documentClient,
+      });
+
+      // ACT
+      const result = await repo.update(itemWithoutField1);
+
+      // ASSERT
+      expect(result.map1).toEqual(newMap);
+      expect(result.field1).toEqual(item.field1);
+    });
+  });
 });