記一次gateway微服務啟動報錯

 這個gateway微服務之前啟動沒題，改了一下父依賴就啟動不了了。

之前的父依賴是springboot-parent，後來我想把這個微服務改在我項目的父依賴下，就改了一下父依賴。

<parent>
            <!--<groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.9.RELEASE</version>
            <relativePath/>-->
        <artifactId>ac-mall-cloud</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
           

改完就報錯了。 

錯誤資訊如下：

Description:

Parameter 0 of method redisRateLimiter in org.springframework.cloud.gateway.config.GatewayRedisAutoConfiguration required a single bean, but 2 were found:
	- reactiveStringRedisTemplate: defined by method 'reactiveStringRedisTemplate' in class path resource [org/springframework/boot/autoconfigure/data/redis/RedisReactiveAutoConfiguration.class]
	- stringReactiveRedisTemplate: defined by method 'stringReactiveRedisTemplate' in class path resource [org/springframework/cloud/gateway/config/GatewayRedisAutoConfiguration.class]


Action:

Consider marking one of the beans as @Primary, updating the consumer to accept multiple beans, or using @Qualifier to identify the bean that should be consumed
           

大緻意思就是在org.springframework.cloud.gateway.config.GatewayRedisAutoConfiguration這個配置類中有兩個redisRateLimiter的執行個體，沖突了。然後我看了下引入的依賴的pom檔案，又看了下其他子服務的pom檔案，發現gateway微服務裡的依賴和父服務裡引入的依賴沖突了，多引了依賴。

下面是gateway微服務中的依賴：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
            <!--<groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.9.RELEASE</version>
            <relativePath/>-->
        <artifactId>ac-mall-cloud</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.ac</groupId>
    <artifactId>gateway-service</artifactId>

    <properties>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
        <alibaba.cloud.version>2.1.0.RELEASE</alibaba.cloud.version>
    </properties>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${alibaba.cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

        ......
    
</project>
           

 下面是父依賴中的pom檔案：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>ac-mall-cloud</artifactId>
    <version>1.0-SNAPSHOT</version>

        ......

    <packaging>pom</packaging>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Hoxton.SR8</spring-cloud.version>
        <alibaba.cloud.version>2.2.5.RELEASE</alibaba.cloud.version>
    </properties>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-parent</artifactId>
                <version>${boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${alibaba.cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        
            ......

         </dependencies>
     </dependencyManagement>
          ......
   </project>
           

 從這兩個pom檔案可以看到，在父依賴中已經引入了springcloud依賴和alibabacloud依賴，而且版本和gateway中的版本也不一樣，把gateway微服務pom檔案改成下面這種就可以啟動了。

把所有父依賴pom中已經引入過的依賴注釋掉就可以了。

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
            <!--<groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.9.RELEASE</version>
            <relativePath/>-->
        <artifactId>ac-mall-cloud</artifactId>
        <groupId>org.example</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.ac</groupId>
    <artifactId>gateway-service</artifactId>

    <!--<properties>
        <spring-cloud.version>Greenwich.SR3</spring-cloud.version>
        <alibaba.cloud.version>2.1.0.RELEASE</alibaba.cloud.version>
    </properties>-->

    <!--<dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${alibaba.cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>-->
        
        ......

 </project>