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

问题描述

我有春季启动应用程序。

我试图从tomcat位置访问application.properties文件。

我遵循此链接：

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软件基金会\\ 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软件基金会\\ 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，因为未找到数据库连接。

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).

让我知道如何解决此问题。或者是否还有其他方法可以使用Spring Boot从tomcat位置访问属性文件。

从tomcat目录访问application.properties文件。 那么我们需要遵循以下步骤

需要在pom.xml添加插件。 这意味着部署后它将忽略工作区的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目录的lib位置。 那么我们需要更改ServletInitializer.java文件。

"classpath:mortgage-api/"表示我们需要在tomcat的lib文件夹中创建一个名称为mortgage-api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