字段dataSource在org.o7planning.aboutcompany.MainController中需要一个无法找到的'javax.sql.DataSource‘类型的bean

Question

我参考了URL：https://o7planning.org/en/11727/understanding-spring-cloud-config-client-with-example，没有任何定制，但试图简单地运行以下错误的代码。谁能指点我出什么事了吗？

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2018-04-08 23:45:00.960 ERROR 5476 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Field dataSource in org.o7planning.aboutcompany.MainController required a bean of type 'javax.sql.DataSource' that could not be found.
    - Bean method 'dataSource' not loaded because @ConditionalOnProperty (spring.datasource.jndi-name) did not find property 'jndi-name'
    - Bean method 'dataSource' not loaded because @ConditionalOnClass did not find required class 'javax.transaction.TransactionManager'


Action:

Consider revisiting the conditions above or defining a bean of type 'javax.sql.DataSource' in your configuration.

以下是参考bootstrap.properties的代码

spring.application.name=app-about-company
spring.cloud.config.uri=http://localhost:8888
management.security.enabled=false

application.properties

server.port=7777

MainController

@RefreshScope
@RestController
public class MainController {
    @Value("${text.copyright: Default Copyright}")
    private String copyright;

    @Value("${spring.datasource.driver-class-name}")
    private String driverClassName;

    @Value("${spring.datasource.url}")
    private String url;

    @Value("${spring.datasource.username}")
    private String userName;

    @Value("${spring.datasource.password}")
    private String password;

    @Autowired
    private DataSource dataSource;

    @RequestMapping("/showConfig")
    @ResponseBody
    public String showConfig() {
        String configInfo = "Copy Right: " + copyright //
                + "<br/>spring.datasource.driver-class-name=" + driverClassName //
                + "<br/>spring.datasource.url=" + url //
                + "<br/>spring.datasource.username=" + userName //
                + "<br/>spring.datasource.password=" + password;

        return configInfo;
    }

    @RequestMapping("/pingDataSource")
    @ResponseBody
    public String pingDataSource() {
        try {
            return this.dataSource.toString();
        } catch (Exception e) {
            e.printStackTrace();
            return "Error: " + e.getMessage();
        }
    }
}

pom.xml

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Finchley.BUILD-SNAPSHOT</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-config</artifactId>
        </dependency>

        <dependency>
            <groupId>com.microsoft.sqlserver</groupId>
            <artifactId>mssql-jdbc</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <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>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

    <repositories>
        <repository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>

Answer 1

你错过了一个DataSource豆。根据错误消息，此bean的自动注册失败：

- Bean method 'dataSource' not loaded because @ConditionalOnProperty (spring.datasource.jndi-name) did not find property 'jndi-name'
- Bean method 'dataSource' not loaded because @ConditionalOnClass did not find required class 'javax.transaction.TransactionManager'

基于上述，您很可能需要包含javax.transaction:javax.transaction-api:1.2依赖项来提供javax.transaction.TransactionManager类。基于读取spring.datasource.*连接属性的代码，您没有使用JNDI。

您可以通过运行mvn dependency:tree来检查是否已经有此依赖项。由于没有提供完整的pom.xml，很难判断您已经有哪些依赖项。