CoApiZero-boilerplate HTTP Clients for Spring 6

Define an interface, annotate it, done. Reactive & synchronous, with client-side load balancing.

@CoApi Annotation

Mark any interface with @CoApi — CoApi auto-configures the HTTP client, proxy bean, and all supporting infrastructure. Zero boilerplate.

Reactive & Synchronous

Switch between WebClient (reactive) and RestClient (synchronous) with a single property. Or let CoApi infer from your classpath.

Client-Side Load Balancing

Integrated with Spring Cloud LoadBalancer. Use serviceId or lb:// protocol for automatic instance selection across microservices.

Spring Boot Auto-Configuration

Add the starter dependency and @CoApi interfaces are auto-discovered via classpath scanning. No manual setup required.

Customizable SPI

Hook into client creation with WebClientBuilderCustomizer or RestClientBuilderCustomizer. Configure filters, interceptors, and connection pools per client.

Built-in Auth

BearerTokenFilter with JWT-aware reactive token caching. Token is fetched once, cached, and automatically refreshed on expiry.