A simple Java application that uses Plain Jane JDBC to connect to a local Postgres instance; what's more, it also connects to a local ReadySet instance (via port 5433). Both ReadySet and Postgres can be run via a docker compose command.

To run everything, you need to have the following installed:

1. Java version 21
2. Gradle 8.5
3. Docker Engine

The two files worth looking at are AppTest.java found in the app/src/test/java/io/readyset/bygone/ directory and the Employee.java file in the app/src/main/java/io/readyset/bygone/ directory. The former class drives the latter; what's more, there are only two queries present. One is a simple point query and the other does a three way join. Both queries are supported by ReadySet. There's a lot more that can be added to this project, but it's good enough for now to demonstrate simple JDBC reads.

1. First, clone this repository and then change directories into bygone-era.

2. Decompress the employees_data.sql.bz2 file by running:

   $ bunzip2 employees_data.sql.bz2
   

   Note, you may need to install bzip2.

3. Next, run gradle composeUp, which will start two containers. One container is named postgres-primary and exposes port 5432 and the other cache. It's exposed on port 5434. The latter container depends on the primary instance starting up successfully. When Postgres starts up, it'll execute the employees_data.sql file, which will create a large employee-like database. Additionally, ReadySet will start up and snapshot this database (this might take 2-3 minutes).

4. I'm lazy and am making this step manual for now: wait about a minute for ReadySet to snapshot. You can check the logs for ReadySet and look for the line that says streaming replication has started and then you know things are good go. Once ReadySet is ready, run gradle test.

5. The previous step will run 4 JUnit tests successfully if Postgres and ReadySet are running. Shell into ReadySet via psql postgresql://postgres:hoodoo@localhost:5433/hoodoo and issue a show proxied queries command. You should see two cache-able queries. Cache them via the create cache from <cache_id> command.

6. Rerun gradle test to verify that JDBC is going through ReadySet now!

7. You can shut both Docker containers down via the gradle composeDown command.

1. Employees database for Postgres
2. Bitnami Docker distribution documentation
3. Gradle Docker Compose plugin