Concurrent Data Processing in Elixir

Broadway Callbacks In Depth

Now that we have the tickets project set up, we are ready to start writing some code. Once a message comes from the message broker, we want to use it to create a ticket in the database for the customer and send a confirmation email to them.

To accomplish this, we are going to use the Broadway behaviour to configure and start the data-ingestion pipeline. There are four callbacks available for us to implement:

• handle_message/3
• prepare_messages/2
• handle_failed/2
• handle_batch/4

In this section, we’ll focus on the first three callbacks in the list. Don’t worry, we’re going to cover handle_batch/4 soon in ​Batching Messages​.

First, create a new file bookings_pipeline.ex in the lib folder. Then define the module BookingsPipeline ...