When learning how to integrate spring cloud with Alibaba, we encountered an openfeign call error

Caused by: java.lang.IllegalStateException: No Feign Client for loadBalancing defined. Did you forget to include spring-cloud-starter-loadbalancer?
	at org.springframework.cloud.openfeign.FeignClientFactoryBean.loadBalance(FeignClientFactoryBean.java:309) ~[spring-cloud-openfeign-core-3.0.0.jar:3.0.0]
	at org.springframework.cloud.openfeign.FeignClientFactoryBean.getTarget(FeignClientFactoryBean.java:335) ~[spring-cloud-openfeign-core-3.0.0.jar:3.0.0]
	at org.springframework.cloud.openfeign.FeignClientFactoryBean.getObject(FeignClientFactoryBean.java:315) ~[spring-cloud-openfeign-core-3.0.0.jar:3.0.0]
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:169) ~[spring-beans-5.3.3.jar:5.3.3]
	... 47 common frames omitted

Baidu found that openfeign 3.0.0 built in spring cloud 2020.0.0 conflicts with Nacos framework of spring cloud Alibaba.

Here are two solutions

Methond 1

First add the loadbalancer dependency in pom.xml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-loadbalancer</artifactId>
</dependency>

Because nacos dependencies containing ribbon dependencies will cause loadbalancer to be invalid, you need to exclude the ribbon dependencies from nacos dependencies.

<dependency>
	<groupId>com.alibaba.cloud</groupId>
	<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
	<exclusions>
		<exclusion>
			<artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
			<groupId>org.springframework.cloud</groupId>
		</exclusion>
	</exclusions>
</dependency>

Method 2

 <!-- spring cloud 2020.0.0built-in openfeign3.0.0 and spring cloud alibaba framework nacos, seata conflict temporary solution - >
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
            <version>2.2.6.RELEASE</version>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-starter</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-openfeign-core</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-commons</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter</artifactId>
            <version>2.2.6.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-openfeign-core</artifactId>
            <version>2.2.6.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-commons</artifactId>
            <version>2.2.6.RELEASE</version>
        </dependency>