Provider-Composer Spring Boot Starter

通用的 Provider-Composer 异步编排模式 Spring Boot Starter。

将多数据源异步聚合查询的编排逻辑封装为开箱即用的组件，支持按优先级分阶段并行执行、结果统一组装。

快速开始

1. 添加依赖

<dependency>
    <groupId>com.dolbyhub</groupId>
    <artifactId>provider-composer-spring-boot-starter</artifactId>
    <version>1.0.0</version>
</dependency>

2. 实现 DataProvider

每个 Provider 负责从一个数据源获取数据：

@Component
public class UserBasicInfoProvider implements DataProvider<String, UserInfo> {

    @Override
    public String getName() {
        return "user-basic";
    }

    @Override
    public int getOrder() {
        return 10; // 同 order 并行，不同 order 串行
    }

    @Override
    public UserInfo apply(String userId) {
        return userService.getBasicInfo(userId);
    }
}

@Component
public class UserOrderProvider implements DataProvider<String, List<Order>> {

    @Override
    public String getName() {
        return "user-orders";
    }

    @Override
    public int getOrder() {
        return 10; // 与 UserBasicInfoProvider 同一批并行执行
    }

    @Override
    public List<Order> apply(String userId) {
        return orderService.getOrders(userId);
    }
}

@Component
public class UserCreditProvider implements DataProvider<String, CreditInfo> {

    @Override
    public String getName() {
        return "user-credit";
    }

    @Override
    public int getOrder() {
        return 20; // 等第一批完成后再执行
    }

    @Override
    public CreditInfo apply(String userId) {
        return creditService.getCreditInfo(userId);
    }
}

3. 实现 ResultComposer（可选）

@Component
public class UserResultComposer implements ResultComposer<UserProfileResponse> {

    @Override
    public UserProfileResponse compose(Map<String, Object> source) {
        UserProfileResponse response = new UserProfileResponse();
        response.setBasicInfo((UserInfo) source.get("user-basic"));
        response.setOrders((List<Order>) source.get("user-orders"));
        response.setCreditInfo((CreditInfo) source.get("user-credit"));
        return response;
    }
}

4. 在 Service 中使用

方式一：使用 ProviderExecutorFactory

@Service
public class UserQueryService {
    private final ProviderExecutorService<String> executor;
    private final UserResultComposer composer;

    public UserQueryService(ProviderExecutorFactory factory,
                           ApplicationContext context,
                           UserResultComposer composer) {
        this.executor = factory.create(context, DataProvider.class);
        this.composer = composer;
    }

    public UserProfileResponse queryUser(String userId) 
            throws ExecutionException, InterruptedException {
        return executor.executeAndCompose(userId, composer);
    }
}

方式二：手动创建 ProviderExecutorService

@Service
public class UserQueryService {
    private final ProviderExecutorService<String> executor;

    public UserQueryService(ApplicationContext context,
                           @Qualifier("providerComposerExecutor") Executor exec) {
        Collection<DataProvider> providers = context.getBeansOfType(DataProvider.class).values();
        this.executor = new ProviderExecutorService<>(providers, exec);
    }

    public Map<String, Object> queryUser(String userId) 
            throws ExecutionException, InterruptedException {
        return executor.executeAsync(userId);
    }
}

5. 配置线程池（可选）

ops:
  provider-composer:
    enabled: true
    core-pool-size: 10
    max-pool-size: 20
    queue-capacity: 200
    thread-name-prefix: biz-provider-
    keep-alive-seconds: 120

执行策略

通过 getOrder() 控制执行顺序：

order 值	行为
相同	同一批次 并行执行（CompletableFuture.allOf）
不同	按 order 从小到大 串行分批执行
默认 (MAX_VALUE)	所有未指定 order 的 Provider 合并到同一批并行执行

示例：假设有 5 个 Provider，order 分别为 10, 10, 10, 20, 30

Batch 0 (order=10): [A, B, C]  → 并行执行，allOf().get() 等待
Batch 1 (order=20): [D]        → 串行执行，allOf().get() 等待
Batch 2 (order=30): [E]        → 串行执行，allOf().get() 等待

核心类

类	说明
DataProvider<I, O>	通用 Provider 接口，继承 Function<I, O>
ResultComposer<R>	结果组装器接口
NoOpResultComposer	默认透传 Composer
ProviderExecutorService<I>	核心异步编排引擎
ProviderExecutorFactory	便捷工厂
ProviderComposerProperties	线程池配置属性
ProviderComposerAutoConfiguration	自动配置类