Spring Boot Integration Experiments

This repository contains a collection of sample projects and experiments showcasing various Spring Boot integrations and features. The goal is to help you explore new possibilities, demonstrate best practices, and provide ready-to-use examples.

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Table of Contents

• Overview
• Projects
• Tech Stack
• Useful Docker Commands
• Useful git Commands

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Overview

Each subdirectory in this repository demonstrates a focused aspect of Spring Boot development ranging from database integrations, caching, messaging, and multi-tenancy to advanced topics like Chaos Engineering and observability.

Key Features:

1. Wide Range of Integrations: Explore different databases (MySQL, PostgreSQL, MongoDB, Oracle), caching with Redis, and advanced topics like multi-tenancy.
2. Observability & Monitoring: Many samples include Prometheus, Grafana, or Kibana. They demonstrate setting up and analyzing application performance in real-time.
3. Scalability & Resilience Patterns: Investigate Chaos Monkey for injecting controlled failures, or look at multi-database solutions for horizontal scaling.

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Projects

Below is a quick lookup table summarizing each sub-project. For more details, check their individual README.md files.

Name	Description
Spring Batch Implementation	Demonstrates how to use Spring Batch 5 with a straightforward configuration.
Archunit Implementation	Shows how to enforce architectural constraints in a Spring Boot project using ArchUnit.
Chaos Engineering Principles	Covers applying Chaos Engineering with Spring Boot, along with performance tests.
Grafana LGTM	Demonstrates an observability stack with Loki, Grafana, Tempo, and Mimir.
HTTP Proxy Implementation	Implements HTTP proxy functionality for routing and managing HTTP requests.
JMH Benchmark	Provides microbenchmarking capabilities using JMH for measuring code performance.
Mongodb and Elasticsearch Reactive integration	Illustrates storing data in MongoDB, then retrieving it using reactive Elasticsearch.
OpenAPI Implementation	Demonstrates OpenAPI specification generation and documentation using Swagger.
Opensearch Integration	Showcases saving data and performing swift geospatial searches in OpenSearch.
Rabbit Mq Implementation	Demonstrates RabbitMQ producer acknowledgments, a Dead Letter Queue setup, and more.
Rest API Documentation with examples	Highlights generating PDF documentation of RESTful APIs using Spring REST Docs.
RestClient Implementation	Introduces Spring 6's RestClient as a modern alternative to WebClient/RestTemplate.
RestTemplate Implementation	Shows how to use Spring's RestTemplate for making HTTP requests to RESTful services.
Implementation of Strategy Design Pattern	Uses the Strategy Pattern within a Spring application, builds a native image.
Feature Toggles	Demonstrates toggling specific features on or off at runtime in a Spring Boot application.
Ultimate Redis Implementation	Explores multiple Redis usage patterns with varying time-to-live (TTL) settings.
WebClient MVC Implementation	Demonstrates using WebClient with Spring MVC for HTTP operations.
WebClient WebFlux Implementation	Shows WebClient usage with WebFlux for reactive HTTP operations.
Graph QL implementation using QueryDSL	Illustrates integrating GraphQL with QueryDSL to interact with a database.
Graph QL implementation using webflux	Showcases using GraphQL alongside the reactive WebFlux stack for asynchronous processing.
Graph QL implementation using webmvc	Demonstrates applying GraphQL concepts with the traditional Spring MVC for synchronous processing.
Custom SequenceNumber and LazyConnectionDataSourceProxy	Highlights creating custom sequence generators and optimizing database connections.
Hibernate Envers Implementation using spring data JPA	Shows how to track entity revisions with Hibernate Envers and monitor system changes.
Connecting to multiple data sources	Demonstrates configuring multiple SQL databases in a single Spring Boot application.
Hibernate 2nd Level Cache Using Redis	Explains configuring Hibernate's second-level caching via Redis and testing it.
JNDI Sample	Demonstrates JNDI usage with embedded Tomcat and Hikari DataSource.
JPA with JOOQ	Shows how to use both JPA and JOOQ in the same application for database operations.
JPA Locks	Demonstrates database locking mechanisms and transaction isolation levels.
Read Replica Postgres with connection optimization	Illustrates writing data to a primary Postgres database, then reading from a replica.
KeySet pagination and dynamic search with Blaze	Implements keyset pagination using Blaze Persistence, adding dynamic query features.
KeySet pagination and dynamic search with spring data jpa	Implements keyset pagination using Spring Data JPA, enabling dynamic queries.
MultiTenancy with multipledatsources	Provides examples of running multi-tenant applications under different strategies.
MultiTenancy DB Based	Demonstrates having each tenant use a separate database (while sharing the same codebase).
MultiTenancy Partition Based	Shows how to share a single database and table across tenants using a partitioning strategy.
MultiTenancy Schema Based	Demonstrates isolating tenants by allocating a separate schema for each tenant.
Reactive SQL With JOOQ	Explains performing reactive CRUD operations in Spring Boot using jOOQ.
PostgreSQL JSON and ENUM column support using reactive	Demonstrates PostgreSQL JSON and ENUM column support in a reactive application.
PostgreSQL Notify/Listen	Shows how to implement PostgreSQL's NOTIFY/LISTEN feature using R2DBC.
Reactive Cache with Redis	Demonstrates caching reactive database operations in Redis to boost performance.
Reactive Application	Illustrates an end-to-end reactive CRUD workflow in Spring Boot using R2DBC.
BackgroundJobs and Scheduling using Jobrunr	Sets up background job scheduling with Jobrunr.
Scheduling using Quartz	Showcases the Quartz Scheduler, providing job scheduling capabilities.
Scheduling using Database Distributed Locks with ShedLock	Demonstrates scheduling while ensuring only one active job running at a time using ShedLock.

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Tech Stack

This repository leverages a broad stack of technologies, including:

• Java / JavaScript / SQL for core logic & data.
• Spring Framework (Boot, Data, Security, etc.) as the key application framework.
• Project Reactor for reactive data flows and concurrency.
• QueryDSL, Liquibase, Flyway, JOOQ for advanced database interactions and migrations.
• Docker, Docker Compose for containerization and multi-service orchestration.
• RabbitMQ, Redis, Elasticsearch, OpenSearch, MongoDB for messaging, caching, and search.
• Gradle / Maven for builds and dependency management.
• GitHub Actions, CircleCI, Jenkins for CI/CD pipelines.

For in-depth version references, visit techstack.md or see individual project READMEs.

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Useful Docker Commands

Start Postgres and pgAdmin

docker compose up postgres pgadmin4

Clean up everything using

docker system prune -a -f --volumes

Claim unused volumes

docker volume prune

Running container

docker container ls

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Useful git Commands

How to overwrite local changes with git pull

Stash local changes:

git stash

Pull changes from remote:

git pull

How to revert the changes that are pushed to remove

git revert $hash