Spring Boot 3.x for Backend Services

HDIM requires a backend framework for 28 microservices that provides:

Chosen option: "Spring Boot 3.x"

Rationale: Spring Boot 3.x provides:

Mitigations:

Enterprise Java framework from VMware/Pivotal.

| Criterion | Assessment |

|-----------|------------|

| HAPI FHIR Integration | Good - Native Spring Boot starters |

| Security | Good - Spring Security is industry standard |

| Observability | Good - Actuator provides comprehensive metrics |

| Database | Good - Spring Data JPA for PostgreSQL |

| Messaging | Good - Spring Kafka integration |

| Healthcare Adoption | Good - Dominant in healthcare Java |

| Performance | Neutral - JVM overhead, but optimized |

Summary: Best fit for healthcare Java microservices with HAPI FHIR.

Cloud-native Java framework from Red Hat.

| Criterion | Assessment |

|-----------|------------|

| HAPI FHIR Integration | Neutral - Requires manual integration |

| Security | Good - Quarkus Security available |

| Startup Time | Good - Native compilation option |

| Memory | Good - Lower than Spring Boot |

| Healthcare Adoption | Neutral - Less common in healthcare |

| Ecosystem Size | Neutral - Smaller than Spring |

Summary: Good for cloud-native but HAPI FHIR integration less mature.

Lightweight Java framework.

| Criterion | Assessment |

|-----------|------------|

| HAPI FHIR Integration | Neutral - Requires manual integration |

| Security | Good - Micronaut Security available |

| Startup Time | Good - AOT compilation |

| Memory | Good - Lower than Spring Boot |

| Healthcare Adoption | Neutral - Limited healthcare deployments |

| Documentation | Neutral - Less extensive than Spring |

Summary: Lightweight alternative but smaller ecosystem.

JavaScript/TypeScript framework.

| Criterion | Assessment |

|-----------|------------|

| HAPI FHIR Integration | Bad - HAPI FHIR is Java only |

| Security | Neutral - Passport.js available |

| Performance | Neutral - Good for I/O, less for compute |

| Healthcare Adoption | Bad - Rare in healthcare backend |

| CQL Engine | Bad - CQL Engine is Java only |

Summary: Not viable due to Java library dependencies (HAPI FHIR, CQL).

Go-based microservices.

| Criterion | Assessment |

|-----------|------------|

| HAPI FHIR Integration | Bad - HAPI FHIR is Java only |

| Performance | Good - Excellent performance and memory |

| Startup Time | Good - Fast startup |

| Healthcare Adoption | Neutral - Growing but Java dominant |

| CQL Engine | Bad - CQL Engine is Java only |

Summary: Not viable due to Java library dependencies.

Spring Boot 3.2.x with Java 21 LTS

// build.gradle.kts
dependencies {
    // Spring Boot
    implementation("org.springframework.boot:spring-boot-starter-web")
    implementation("org.springframework.boot:spring-boot-starter-data-jpa")
    implementation("org.springframework.boot:spring-boot-starter-security")
    implementation("org.springframework.boot:spring-boot-starter-actuator")
    implementation("org.springframework.boot:spring-boot-starter-validation")

    // Kafka
    implementation("org.springframework.kafka:spring-kafka")

    // Redis
    implementation("org.springframework.boot:spring-boot-starter-data-redis")

    // HAPI FHIR
    implementation("ca.uhn.hapi.fhir:hapi-fhir-spring-boot-starter:7.0.2")

    // Observability
    implementation("io.micrometer:micrometer-registry-prometheus")

    // Database
    runtimeOnly("org.postgresql:postgresql")

    // Testing
    testImplementation("org.springframework.boot:spring-boot-starter-test")
    testImplementation("org.springframework.security:spring-security-test")
    testImplementation("org.testcontainers:postgresql")
}

com.healthdata.{service}/
├── api/
│   └── v1/                  # REST controllers
├── application/             # Application services
├── domain/
│   ├── model/              # Domain entities
│   └── repository/         # Repository interfaces
├── infrastructure/
│   ├── persistence/        # JPA implementations
│   ├── messaging/          # Kafka producers/consumers
│   └── external/           # External service clients
└── config/                 # Spring configuration

server:

port: ${SERVER_PORT:8080}

spring:

application:

name: ${SERVICE_NAME:service}

datasource:

url: jdbc:postgresql://${POSTGRES_HOST:localhost}:${POSTGRES_PORT:5435}/${POSTGRES_DB:healthdata_qm}

username: ${POSTGRES_USER:healthdata}

password: ${POSTGRES_PASSWORD}

jpa:

hibernate:

ddl-auto: validate

open-in-view: false # Performance best practice

kafka:

bootstrap-servers: ${KAFKA_BOOTSTRAP_SERVERS:localhost:9094}

management:

endpoints:

web:

exposure:

include: health,info,metrics,prometheus

endpoint:

health:

show-details: when_authorized

@Configuration
@EnableWebSecurity
@EnableMethodSecurity
public class SecurityConfig {

    @Bean
    public SecurityFilterChain securityFilterChain(
            HttpSecurity http,
            TrustedHeaderAuthFilter trustedHeaderAuthFilter,
            TrustedTenantAccessFilter trustedTenantAccessFilter) throws Exception {

        http
            .csrf(csrf -> csrf.disable())
            .sessionManagement(session ->
                session.sessionCreationPolicy(SessionCreationPolicy.STATELESS))
            .authorizeHttpRequests(auth -> auth
                .requestMatchers("/actuator/health/**").permitAll()
                .requestMatchers("/api/**").authenticated()
                .anyRequest().denyAll())
            .addFilterBefore(trustedHeaderAuthFilter,
                UsernamePasswordAuthenticationFilter.class)
            .addFilterAfter(trustedTenantAccessFilter,
                TrustedHeaderAuthFilter.class);

        return http.build();
    }
}

@SpringBootTest
@AutoConfigureMockMvc
@Testcontainers
class PatientControllerTest {

    @Container
    static PostgreSQLContainer<?> postgres =
        new PostgreSQLContainer<>("postgres:16");

    @Autowired
    private MockMvc mockMvc;

    @Test
    @WithMockUser(roles = "ADMIN")
    void shouldReturnPatient() throws Exception {
        mockMvc.perform(get("/api/v1/patients/{id}", "123")
                .header("X-Tenant-ID", "tenant1"))
            .andExpect(status().isOk())
            .andExpect(jsonPath("$.id").value("123"));
    }
}

./gradlew build

./gradlew :modules:services:quality-measure-service:build

./gradlew test

./gradlew bootJar

java -jar service.jar --spring.profiles.active=prod

| Version | Date | Author | Changes |

|---------|------|--------|---------|

| 1.0 | 2024-Q3 | Architecture Team | Initial decision |

| 1.1 | 2024-12-30 | Architecture Team | Added code examples, build commands |

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