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There is a newer version: 0.4.0
package com.github.linyuzai.dynamicfeign.targeter;

import com.github.linyuzai.dynamicfeign.factory.DynamicFeignClientFactoryBean;
import feign.Feign;
import feign.Target;
import feign.hystrix.FallbackFactory;
import feign.hystrix.HystrixFeign;
import feign.hystrix.SetterFactory;
import org.springframework.cloud.openfeign.FeignContext;

@SuppressWarnings("unchecked")
public class HystrixTargeter implements Targeter {

    @Override
    public  T target(DynamicFeignClientFactoryBean factory, Feign.Builder feign, FeignContext context,
                        Target.HardCodedTarget target) {
        if (!(feign instanceof feign.hystrix.HystrixFeign.Builder)) {
            return feign.target(target);
        }
        feign.hystrix.HystrixFeign.Builder builder = (feign.hystrix.HystrixFeign.Builder) feign;
        SetterFactory setterFactory = getOptional(factory.getName(), context,
                SetterFactory.class);
        if (setterFactory != null) {
            builder.setterFactory(setterFactory);
        }
        Class fallback = factory.getFallback();
        if (fallback != void.class) {
            return targetWithFallback(factory.getName(), context, target, builder, fallback);
        }
        Class fallbackFactory = factory.getFallbackFactory();
        if (fallbackFactory != void.class) {
            return targetWithFallbackFactory(factory.getName(), context, target, builder, fallbackFactory);
        }

        return feign.target(target);
    }

    private  T targetWithFallbackFactory(String feignClientName, FeignContext context,
                                            Target.HardCodedTarget target,
                                            HystrixFeign.Builder builder,
                                            Class fallbackFactoryClass) {
        FallbackFactory fallbackFactory = (FallbackFactory)
                getFromContext("fallbackFactory", feignClientName, context, fallbackFactoryClass, FallbackFactory.class);
        return builder.target(target, fallbackFactory);
    }


    private  T targetWithFallback(String feignClientName, FeignContext context,
                                     Target.HardCodedTarget target,
                                     HystrixFeign.Builder builder, Class fallback) {
        T fallbackInstance = getFromContext("fallback", feignClientName, context, fallback, target.type());
        return builder.target(target, fallbackInstance);
    }

    private  T getFromContext(String fallbackMechanism, String feignClientName, FeignContext context,
                                 Class beanType, Class targetType) {
        Object fallbackInstance = context.getInstance(feignClientName, beanType);
        if (fallbackInstance == null) {
            throw new IllegalStateException(String.format(
                    "No " + fallbackMechanism + " instance of type %s found for feign client %s",
                    beanType, feignClientName));
        }

        if (!targetType.isAssignableFrom(beanType)) {
            throw new IllegalStateException(
                    String.format(
                            "Incompatible " + fallbackMechanism + " instance. Fallback/fallbackFactory of type %s is not assignable to %s for feign client %s",
                            beanType, targetType, feignClientName));
        }
        return (T) fallbackInstance;
    }

    private  T getOptional(String feignClientName, FeignContext context,
                              Class beanType) {
        return context.getInstance(feignClientName, beanType);
    }
}