java-microservice

name: java-microservice description: Java 25 microservice development patterns for crypto-scout-client including modules, AMQP publishing, and WebSocket consumers license: MIT compatibility: opencode metadata: language: java framework: activej version: "0.0.1" domain: microservice

What I Do

Provide guidance for developing and maintaining the crypto-scout-client microservice, a Java 25 Maven application that collects crypto market data and publishes to RabbitMQ Streams.

Architecture

Client.java (Launcher)
├── CoreModule - Reactor and executor (virtual threads)
├── ServiceGraphModule - ActiveJ service lifecycle
├── JmxModule - JMX monitoring
├── ClientModule - AMQP publisher lifecycle
├── BybitSpotModule/BybitLinearModule - WebSocket consumers (conditional on bybit.stream.module.enabled)
├── CmcParserModule - HTTP parser consumer (conditional on cmc.parser.module.enabled)
└── WebModule - HTTP server, health endpoint, DNS

Core Components

Modules

ActiveJ DI modules for separation of concerns:

AmqpPublisher

Thread-safe publisher that routes structured events to RabbitMQ Streams:

// Routes payloads to configured streams based on provider/source
// Bybit data -> bybit-stream (configured via amqp.bybit.stream)
// CMC data -> crypto-scout-stream (configured via amqp.crypto.scout.stream)
amqpPublisher.publish(payload);

Bybit Stream Consumers

WebSocket consumers extending AbstractBybitStreamConsumer:

// AbstractBybitStreamConsumer base class provides common lifecycle
BybitSpotBtcUsdtConsumer   // Spot BTC/USDT market data
BybitSpotEthUsdtConsumer   // Spot ETH/USDT market data
BybitLinearBtcUsdtConsumer // Linear BTC/USDT market data
BybitLinearEthUsdtConsumer // Linear ETH/USDT market data

CmcParserConsumer

HTTP-based data collection from CoinMarketCap:

// Retrieves Fear & Greed Index (API Pro Latest)
// Retrieves BTC/USD quotes (1D, 1W timeframes)
// Publishes to crypto-scout-stream

Health Endpoint

// GET /health - returns "ok" (200) when ready, 503 otherwise
// Used for liveness and readiness checks in container orchestration

ConfigValidator

Validates all configuration at startup:

@Override
protected void onStart() throws Exception {
    ConfigValidator.validate(AppConfig.getAsBoolean(CMC_PARSER_MODULE_ENABLED));
}

Configuration

All settings via system properties with environment variable mapping:

Module Loading Pattern

@Override
protected Module getModule() {
    final var modules = new LinkedList<Module>();
    modules.add(JmxModule.create());
    modules.add(ServiceGraphModule.create());
    modules.add(CoreModule.create());
    modules.add(ClientModule.create());

    if (AppConfig.getAsBoolean(BYBIT_STREAM_MODULE_ENABLED)) {
        modules.add(BybitSpotModule.create());
        modules.add(BybitLinearModule.create());
    }

    if (AppConfig.getAsBoolean(CMC_PARSER_MODULE_ENABLED)) {
        modules.add(CmcParserModule.create());
    }

    modules.add(WebModule.create());
    return combine(modules);
}

Key Dependencies

When to Use Me

Use this skill when:

• Implementing new modules or consumers
• Understanding the microservice architecture
• Configuring AMQP publishing and streams
• Working with Bybit WebSocket or CMC HTTP APIs
• Adding health checks or observability features
• Implementing configuration validation