Docker Mysql 8、Docker spring boot - 配置数据源失败：未指定“url”属性

Question

我一直在研究所有可能的排列，但没有成功。

->application.properties

## DATASOURCE
#local connection
#spring.datasource.url=jdbc:mysql://localhost:3306/Apple?useSSL=false&allowPublicKeyRetrieval=true&createDatabaseIfNotExist=true&autoReconnect=true
# docker network connection
spring.datasource.url=jdbc:mysql://mysqldb_container:3306/Apple?useSSL=false&allowPublicKeyRetrieval=true&createDatabaseIfNotExist=true&autoReconnect=true
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

-> build.gradle

plugins {
    id 'org.springframework.boot' version '2.2.4.RELEASE';
    id 'io.spring.dependency-management' version '1.0.9.RELEASE'
    id 'java'
}; group 'org.example'; version '1.0-SNAPSHOT'; sourceCompatibility = 1.8; repositories { mavenCentral() }; dependencies {
    implementation 'org.springframework.boot:spring-boot-starter-web'
    implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
    implementation('mysql:mysql-connector-java'); testCompile group: 'junit', name: 'junit', version: '4.12'
}

-> Dockerfile

From openjdk:8
copy build/libs/Java_Mysql_Docker-1.0-SNAPSHOT.jar java_mysql_docker_jar.jar
CMD ["java","-jar","java_mysql_docker_jar.jar"]

-> docker 命令

docker network create java_mysql_docker_network
docker container run --name mysqldb_container --network java_mysql_docker_network -e MYSQL_ROOT_PASSWORD=root -e MYSQL_DATABASE=Apple -p 3306:3306 -d mysql:8
gradle clean build
docker build -t java_mysql_docker_image .
docker container run --name java_mysql_docker_image_container --network java_mysql_docker_network -p 8080:8080 java_mysql_docker_image

->异常描述：

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.
Reason: Failed to determine a suitable driver class

对于以下 URL 的本地安装的 MySQL 8，相同的应用程序工作正常

spring.datasource.url=jdbc:mysql://localhost:3306/Apple?useSSL=false&allowPublicKeyRetrieval=true&createDatabaseIfNotExist=true&autoReconnect=true

但 Docker MySQL 8 失败

spring.datasource.url=jdbc:mysql://mysqldb_container:3306/Apple?useSSL=false&allowPublicKeyRetrieval=true&createDatabaseIfNotExist=true&autoReconnect=true

Answer 1

我的猜测是。

# This driver is not in the classpath.
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver


# Spring auto-detects the driver based on the JDBC URL. This one. 
# Explicitly setting the driver that is in the class path.
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

您看到的错误是来自 spring-boot 项目的这个类：

https://github.com/spring-projects/spring-boot/blob/master/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/DataSourceBeanCreationFailureAnalyzer。爪哇

春季文档：

https://docs.spring.io/spring-boot/docs/current/reference/html/howto.html

Answer 2

显然评论驱动程序适用于本地安装和 docker MySQL 8。

#spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

但仍然想解释为什么会这样。