In order to experiment with these modules, we first need to manually create a topic and subscription, following the instructions in the official documentation. The samples below only experiment with sending and receiving messages from the Pub/Sub Lite topics and subscriptions.

The spring-pubsublite-kafka contains samples that exemplify a workflow that allows users to port their Kafka applications to Pub/Sub Lite while using Spring as the fascade. They leverage the Pub/Sub Lite-Kafka adapter in order to achieve this. It tests out the possibility of using existing Spring-Kafka modules such as KafkaTemplate and KafkaMessageListenerContainer to publish to Pub/Sub Lite.

- Dependendencies are:

  - [java-pubsublite-kafka](https://github.com/googleapis/java-pubsublite-kafka/tree/main/src/main/java/com/google/cloud/pubsublite/kafka)
  - [java-pubsublite](https://github.com/googleapis/java-pubsublite)
  - [spring-boot/spring-kafka](https://github.com/spring-projects/spring-kafka)
  - [spring-integration-kafka](https://github.com/spring-projects/spring-integration-kafka)

Additionally, this module also includes an implementation of our own version of the KafkaTemplate, called KafkaPubSubLite. The interface of the class appears to communicating with Kafka but in reality, it actuallt talks to Pub/Sub lite. Note that this class is not used anywhere. It is just there to show a different approach to porting applications in Spring between the two messaging services.

The spring-pubsublite module contains a sample for Spring support for using Pub/Sub Lite directly. The samples provide implementation of a Pub/Sub Lite template ( similar in theory to the PubSubTemplate which is currently provided by the Spring Cloud GCP project). It tests out sending and receiving messages to Pub/Sub Lite topics and subscriptions through the template.

The pubsub-lite-kafka module just tests out the Pub/Sub Lite Kafka Quickstart.

The pubsub-lite module just tests out the Pub/Sub Lite Quickstart.

The pubsub module just tests out Pub/Sub through Cloud libraries and the Spring Cloud GCP template.