? Required?  Yes ? Default value[leave blank for none]:  <Leave Blank> Let's add another Book property. Enter an empty property name when done. ? Property name:  bookReleaseYear invoke loopback:property ? Property type:  string ? Required?  No ? Default value[leave blank for none]:  2019 Let's add another Book property. Enter an empty property name when done. ? Property name: <Press Enter to Exit the Wizard> Web server listening at: http://localhost:3010 Browse your REST API at  http://localhost:3010/explorer ? Select the model to create the relationship from:  Author ? Relation type:  has many ? Choose a model to create a relationship with:  Book ? Enter the property name for the relation: (books)  books ? Optionally enter a custom foreign key:  authorId ? Require a through model?  No ? Allow the relation to be nested in REST APIs:  No ? Disable the relation from being included:  No Example 6-17 Creating the model relation 2 Example 6-16 Creating the model relation 1 Now you have created two models. Next let us create the relation between the two  models. 1. Start by the following command in Example 6-16 to create a model relation.  Create the model relation 2. Use Example 6-17 to create the model relation. apic lb relation Now that we have created the app, data source, model, and relations, let us test the API. 1. To run the application on your local host type as in Example 6-18. 2. You will get the localhost url to access the API Explorer. See Example 6-19. node . 3. The API Explorer is an embedded testing that allows you to test your application during  development. Use your browser to access the LoopBack API Explorer as shown in  Figure 6-308 on page 388. Example 6-19 Testing the API 2 Example 6-18 Testing the API 1 Testing the API Chapter 6. Practical agile integration  387