DynamoDBSave

Expected time required: 20 min

In this coding activity, you will get practice saving and updating items using the DynamoDB table DynamoDbAnnotationsLoadSave-Books. The table keeps track of a few different attributes (no doubt a small subset of the true book catalog, but suitable for our needs here).

Creating the DynamoDbAnnotationsLoadSave-Books Table

First, open up AWS and search for the DynamoDB service. Make sure your region is set to "us-west-2".

Once at the DynamoDB page, find and click on the button that says "Create Table".

Fill in the form with the following:

• Table name: DynamoDbAnnotationsLoadSave-Books
• Partition Key: asin
• Sort key: leave blank

Leave the rest of the fields to their default values and click "Create table" at the bottom of the page.

Populating the Table

After you pull down this project, open the terminal and go into this project's root folder. Run the following command:

aws dynamodb batch-write-item --request-items file://main/seeds/Books.json

You should get a response that says:

"UnprocessedItems": {}

To further verify that your items are available in the table, go back to the DynamoDB webpage and click on Items on the far left of the page. You should see your table in the list of tables. Click on your table, and now you should see a book item.

Book POJO

A Book POJO based on the DynamoDbAnnotationsLoadSave-Books DynamoDB table has been provided for you.

The Books table can be found in your AWS Console and is set-up the following way:

asin	author	title	year_published
B00EGMV00W	Baldwin	The Fire Next Time	1963

BookDao

Code for getBook() has been provided for you.

Write code for the saveBook() method in the BookDao class. The saveBook() method should accept an instance of Book and save it to the table.

Complete the test

Find the integration test under the src/integrationTest/java directory. The full classname is BookIntegrationTests

Update the BookIntegrationTests class to instantiate an actual DynamoDBMapper instance, including getting a client via the DynamoDbClientProvider class.

Now, run the test class manually in IntelliJ and make sure you get everything passing.

This test actually saves/retrieves data from the DynamoDB table. This is why we're calling it an integration test (if it were a unit test, we'd put it in src/test/java/... and we'd be mocking the DynamoDBMapper we pass into the DAO).

You can see what happens if you delete/alter the book item in DynamoDB that the test expects to be there. You can use the DynamoDB Console for this, to change the items, just make sure you know what to put back in afterwards to restore the data.

Test away!

Once you've written saveBook() in BookDao and updated BookIntegrationTests, you should be able to pass the tests set-up in the BookIntegrationTests class, which is located in src/integrationTest/.

Reminder: You can run the full test class manually by right-clicking the file in the project view and selecting "Run 'BookIntegrationTests'", or by clicking the double arrows to the left of the class declaration when viewing BookIntegrationTests.

You have completed this pre-work when:

• You have implemented the saveBook() method in the BookDao class.
• You have updated BookIntegrationTests to instantiate a DynamoDBMapper instance.
• The BookIntegrationTests are passing.
• You have committed and pushed your code.
• You have answered the Canvas quiz with a link to your commit on code browser.