mailService | Provides mail template system | Email library

Remove @TestExecutionListeners, since the default listeners should suffice.

If you're using Spring Boot, you should use @MockBean instead of @Mock.

In any case, you have to actually instruct JUnit to use Spring's testing support.

I assume that you are using JUnit 4, since I see @BeforeClass in the example. So I'm basing the following on that assumption (and using Java syntax instead of Kotlin).

You can instruct JUnit 4 to use Spring's testing support via @RunWith(SpringRunner.class). Note, however, that you'll also need to specify where your ApplicationContext configuration is.

For Spring Framework, you can do that with @ContextConfiguration. For Spring Boot, you'll likely want to use @SpringBootTest. Consult the documentation for testing support in Spring Framework and Spring Boot for details.

As a side note, you can also test ApplicationEvent publication without using a mock by using Spring Framework's built-in testing support for application events.

Create a PaymentService class which should contain the method getTotalPayment. Inject this class in EmailSend (tip: please change this class name from EmailSend to EmailSender as class names should be noun) class. And then in PaymentService Class you should interact Data Repository class. Call this getTotalPayment method from the EmailSend class.

Here is the implementation that I found best worked for me:

1 Register the service I wanted to schedule in Startup.cs

You don't need a database for that - you just need to update a value that can be seen in the server's code. You could have a plain Express route that adds client session IDs to a collection, which gets updated when the route is called. Then, just have your loop check whether that client's sent such a request.

With sessions, you could have something like, with a route:

Your URL is flawed. Two options:

1. Use Http.PostAsync("/Contact", stringContent); //no /SendMessage

or

1. In the controller, use [HttpPost("SendMessage")]

and, some unrelated suggestions from codereview :

• don't use .Result:

You can use this one.

Netcat works on your Windows machine for the same reason that MailKit works on your Windows machine.

Your Windows machine has an unblock route to the mail server.

Your Ubuntu server, on the other hand, does not have an unblocked route to the mail server, so it fails to connect there.

You need to figure out your firewall and/or routing tables on your Ubuntu server and fix that to allow connecting to the mail server.

Use Hazelcast distributed lock feature with your own code to ensure you send mail only once. https://docs.hazelcast.com/imdg/4.2/cp-subsystem/fencedlock.html

Validate that Beanstalk is running the latest version of your code. May still be using a container spun up before you added the new mappings.