As you have seen in Chapter 6, Cloud Run is a flexible solution for running containers, and you will use it here again. My approach is to work my way down from the highest abstraction until I find a service that can work within the constraints I have identified, a process I call progressive decomposition, if anyone asks. This is not suitable for Cloud Functions, but Cloud Run seems like a good candidate. You will see in Chapter 14, where services like GKE Autopilot (Kubernetes) would be a better choice, but my principle is to start with the simplest solution and only introduce something more complicated when I reach a limitation. To quote the originator of the theory of constraints:
Technology can bring benefits if, and only if, it diminishes a limitation.
Dr. Eliyahu M. Goldratt
In this case, you have not reached the limitation of Cloud Run, as it can be configured in a slightly different way to support the requirements of a highly available Java and Spring Boot service with fast response times.
Spring Cloud GCP
When working with Spring Boot on Google Cloud, you can use the Spring Cloud GCP libraries to make it even easier to consume Google Cloud services. You will use it to connect to Cloud SQL. Spring Cloud GCP provides familiar Spring abstractions over Google Cloud services. Although it forms part of the Spring Cloud, you can use just the GCP libraries in your application without having to use any of the other Spring Cloud features.
For example, you can use the Spring Data JPA library to access Cloud SQL; that is the approach you are going to take in this chapter. In this project, we will make use of Google Cloud APIs wherever possible. The code is going to “know” it is running Google Cloud. You will use Google APIs for logging and connecting to the database.
Table 7-1 includes a breakdown of the Google Cloud services supported by Spring Cloud GCP for Spring Boot applications. The services supported by Spring Cloud GCP nicely align with the “toolkit” of services used in this book. There are Spring starters for each service, a collection of managed libraries that provide all the required dependencies in your Maven or Gradle configuration.
| Table 7-1. Spring Cloud GCP supported services Category | GCP service | Spring abstraction | Spring starter | |
| Databases | Cloud SQL (MySQL) | Spring JDBC template | spring-cloud-gcp-starter-sql-mysql | |
| Spring Data JPA | spring-cloud-gcp-starter-sql-mysql | |||
| Databases | Cloud SQL (PostgreSQL) | Spring JDBC template | spring-cloud-gcp-starter-sql-postgres | |
| Spring Data JPA | spring-cloud-gcp-starter-sql-postgres | |||
| Cloud Spanner | Spring Data Spanner | spring-cloud-gcp-data-spanner | ||
| Spring Data JPA with Hibernate | spring-cloud-gcp-data-spanner | |||
| Cloud Firestore (Datastore mode) | Spring Data Datastore | spring-cloud-gcp-data-datastore | ||
| Cloud Firestore (Firestore mode) | Spring Reactive Data Firestore | spring-cloud-gcp-data-firestore | ||
| Messaging | Cloud Pub/Sub | Spring Integration | spring-cloud-gcp-starter-pubsub | |
| Spring Cloud Stream | spring-cloud-gcp-pubsub-stream-binder | |||
| Spring Cloud Bus | spring-cloud-gcp-starter-bus-pubsub | |||
| Configuration | Cloud Runtime Configuration | Spring Cloud Config | spring-cloud-gcp-starter-config | |
| Cloud Secret Manager | Spring Cloud Config | spring-cloud-gcp-starter-secretmanager | ||
| Storage | Cloud Storage | Spring Resource | spring-cloud-gcp-starter-storage | |
| Cache | Cloud Memorystore | Spring Data Redis | spring-boot-starter-data-redis | |
| Distributed tracing | Cloud Trace | Zipkin/Brave | spring-cloud-gcp-starter-trace | |
| Centralized logging | Cloud Logging | SLF4J/Logback | com.google.cloud:spring-cloud-gcp-starter-logging | |
| Monitoring metrics | Cloud Monitoring | Micrometer/Prometheus | spring-cloud-gcp-starter-metrics | |
| Security | Cloud Identity-Aware Proxy | Spring Security | spring-cloud-gcp-starter-security-iap |
In this case, you just want to use Cloud SQL and Cloud Logging within Maven, so you need to include three dependencies: spring-cloud-gcp-starter, which is required to use any Spring Cloud GCP functionality, spring-cloud-gcp-starter-sql-postgres for Cloud SQL for PostgreSQL, and spring-cloud-gcp-starter-logging for Cloud Logging. These are added to the pom.xml file.
With the services and libraries you require in place, you can start implementation now.