在 Tomcat 中为 Spring Boot 应用程序访问 externalize application.properties？

Question

我有 Spring Boot 应用程序。

我正在尝试从 tomcat 位置访问 application.properties 文件。

我点击了这个链接：How to externalize application.properties in Tomcat webserver for Spring?

MortgageLoanApiApplication

package com.Mortgage.MortgageLoanAPI;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class MortgageLoanApiApplication {

    public static void main(String[] args) {
        System.setProperty("spring.config.name", "application");
        SpringApplication.run(MortgageLoanApiApplication.class, args);
    }

}

ServletInitializer

package com.Mortgage.MortgageLoanAPI;

import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;

public class ServletInitializer extends SpringBootServletInitializer {

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(MortgageLoanApiApplication.class).properties("spring.config.name: application");
    }

}

C:\Program Files\Apache Software Foundation\Apache Tomcat 8.0.9\bin\setenv.sh

export spring_config_location=C:/Program Files/Apache Software Foundation/Apache Tomcat 8.0.9/conf/

C:\Program Files\Apache Software Foundation\Apache Tomcat 8.0.9\conf\application.properties

spring.datasource.url=jdbc:mysql://localhost:3306/mortgage_loan
spring.datasource.driverClassName=com.mysql.cj.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=root

但是当我运行应用程序或构建应用程序时。它显示错误，因为它没有找到数据库连接。

2019-03-04 10:53:28.318  INFO 2872 --- [           main] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-03-04 10:53:28.325 ERROR 2872 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

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

Description:

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


Action:

Consider the following:
    If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
    If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).

让我知道如何解决这个问题。或者如果有任何其他方式可以访问 使用 Spring Boot 从 tomcat 位置获取属性文件。

Answer 1

请添加-

spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration

或

在类上方使用注解-

@EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class})

https://docs.spring.io/spring-boot/docs/current/reference/html/using-boot-auto-configuration.html

Answer 2

从 tomcat 目录访问 application.properties 文件。那么我们需要按照以下步骤进行

需要在pom.xml 中添加插件。这意味着它会在部署后忽略工作区 application.properties 文件

<!-- Added the below plugin to not include the application.properties inside the war -->
<plugin>
    <artifactId>maven-war-plugin</artifactId>
    <version>2.6</version>
    <configuration>
        <failOnMissingWebXml>false</failOnMissingWebXml>
        <packagingExcludes>
            **/application.properties/
        </packagingExcludes>
    </configuration>
</plugin>

需要将application.properties文件复制到tomcat目录lib位置。那么我们需要修改ServletInitializer.java文件。

"classpath:mortgage-api/" 表示我们需要在 tomcat lib 文件夹中创建一个名为 mortgage-api 的文件夹，并将 application.properties 文件复制到该位置。检查代码注释。

import java.util.Properties;

import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;

public class ServletInitializer extends SpringBootServletInitializer {

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(MortgageLoanApiApplication.class).properties(loadproperties());
    }

    /**
     * Added this method to load properties from the classpath while intializing the server app
     * location of the properties file should be inside tomcat directory:
     *    lib/mortgage-api/application.properties
     * @return
     */
    private Properties loadproperties() {
          Properties props = new Properties();
          props.put("spring.config.location", "classpath:mortgage-api/");
          return props;
       }

}

然后mvn clean，然后构建war文件mvn install