feat: 启动时首选本地文件中数据库的配置进行加载

src/main/java/cn/celess/blog/BlogApplication.java

@@ -3,14 +3,19 @@ package cn.celess.blog;
 import org.mybatis.spring.annotation.MapperScan;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.ApplicationContext;
 import org.springframework.scheduling.annotation.EnableAsync;
 
+/**
+ * @author zheng
+ */
 @SpringBootApplication
 @EnableAsync
 @MapperScan("cn.celess.blog.mapper")
 public class BlogApplication {
+    private static ApplicationContext context;
 
     public static void main(String[] args) {
-        SpringApplication.run(BlogApplication.class, args);
+        context = SpringApplication.run(BlogApplication.class, args);
     }
 }

src/main/java/cn/celess/blog/configuration/DruidConfig.java

@@ -1,41 +1,77 @@
 package cn.celess.blog.configuration;
 
 import com.alibaba.druid.pool.DruidDataSource;
-import org.springframework.beans.factory.annotation.Value;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.Environment;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.util.Properties;
 
 /**
  * @author : xiaohai
  * @date : 2019/03/28 14:26
  */
+@Slf4j
 @Configuration
 public class DruidConfig {
-    @Value("${spring.datasource.url}")
-    private String dbUrl;
 
-    @Value("${spring.datasource.username}")
-    private String username;
+    @Autowired
+    Environment env;
 
-    @Value("${spring.datasource.password}")
-    private String password;
-
-    @Value("${spring.datasource.driver-class-name}")
-    private String driverClassName;
+    public static final String DB_CONFIG_PATH = System.getProperty("user.home") + "/blog/application.properties";
+    public static final String DB_CONFIG_URL_PREFIX = "spring.datasource.url";
+    public static final String DB_CONFIG_USERNAME_PREFIX = "spring.datasource.username";
+    public static final String DB_CONFIG_PASSWORD_PREFIX = "spring.datasource.password";
+    public static final String DB_CONFIG_DRIVER_CLASS_NAME_PREFIX = "spring.datasource.driver-class-name";
 
     @Bean
-    public DruidDataSource druidDataSource() {
-        DruidDataSource dataSource = new DruidDataSource();
-        dataSource.setDriverClassName(driverClassName);
-        // 数据库基本信息
-        dataSource.setUrl(dbUrl);
-        dataSource.setUsername(username);
-        dataSource.setPassword(password);
-
-        // 数据库连接池配置
+    public DruidDataSource initDataSource() throws IOException {
+        DruidDataSource dataSource;
+        File file = new File(DB_CONFIG_PATH);
+        if (file.exists()) {
+            log.debug("从文件中获取数据库配置");
+            dataSource = readConfigFromFile(file);
+        } else {
+            log.debug("默认数据库配置");
+            dataSource = defaultDruidSource();
+        }
         dataSource.setInitialSize(10);
         dataSource.setMinIdle(10);
         dataSource.setMaxActive(100);
         return dataSource;
     }
+
+    private DruidDataSource readConfigFromFile(File file) throws IOException {
+        Properties properties = new Properties();
+        properties.load(new FileInputStream(file));
+        String url = properties.getProperty(DB_CONFIG_URL_PREFIX, null);
+        String username = properties.getProperty(DB_CONFIG_USERNAME_PREFIX, null);
+        String password = properties.getProperty(DB_CONFIG_PASSWORD_PREFIX, null);
+        String className = properties.getProperty(DB_CONFIG_DRIVER_CLASS_NAME_PREFIX, null);
+        if (url == null || username == null || password == null || className == null) {
+            return defaultDruidSource();
+        }
+        DruidDataSource dataSource = new DruidDataSource();
+        dataSource.setDriverClassName(className);
+        dataSource.setUrl(url);
+        dataSource.setUsername(username);
+        dataSource.setPassword(password);
+        return dataSource;
+    }
+
+
+    private DruidDataSource defaultDruidSource() {
+        DruidDataSource dataSource = new DruidDataSource();
+        dataSource.setDriverClassName(env.getProperty(DruidConfig.DB_CONFIG_DRIVER_CLASS_NAME_PREFIX));
+        dataSource.setUrl(env.getProperty(DruidConfig.DB_CONFIG_URL_PREFIX));
+        dataSource.setUsername(env.getProperty(DruidConfig.DB_CONFIG_USERNAME_PREFIX));
+        dataSource.setPassword(env.getProperty(DruidConfig.DB_CONFIG_PASSWORD_PREFIX));
+        return dataSource;
+    }
 }

src/test/java/cn/celess/blog/configuration/DruidConfigTest.java

@@ -0,0 +1,103 @@
+package cn.celess.blog.configuration;
+
+import cn.celess.blog.BaseTest;
+import com.alibaba.druid.pool.DruidDataSource;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.core.env.Environment;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.Properties;
+
+import static org.junit.Assert.*;
+
+public class DruidConfigTest extends BaseTest {
+
+    @Autowired
+    Environment env;
+
+    private File configFile;
+    private File bakConfigFile;
+
+    @Test
+    public void initDataSource() throws IOException {
+
+        DruidConfig druidConfig = new DruidConfig();
+        druidConfig.env = env;
+
+        // 无配置文件
+        assertTrue(!configFile.exists() || configFile.delete());
+        DruidDataSource druidDataSource = druidConfig.initDataSource();
+
+        // 加载初始化时候配置文件的数据库连接
+        assertEquals(env.getProperty(DruidConfig.DB_CONFIG_URL_PREFIX), druidDataSource.getUrl());
+        assertEquals(env.getProperty(DruidConfig.DB_CONFIG_DRIVER_CLASS_NAME_PREFIX), druidDataSource.getDriverClassName());
+        assertEquals(env.getProperty(DruidConfig.DB_CONFIG_USERNAME_PREFIX), druidDataSource.getUsername());
+        assertEquals(env.getProperty(DruidConfig.DB_CONFIG_PASSWORD_PREFIX), druidDataSource.getPassword());
+        assertTrue(configFile.createNewFile());
+
+        // 有配置文件的测试
+        Properties properties = new Properties();
+        properties.load(new FileInputStream(configFile));
+        properties.setProperty(DruidConfig.DB_CONFIG_URL_PREFIX, "jdbc:mysql://localhost:3306/blog");
+        properties.setProperty(DruidConfig.DB_CONFIG_DRIVER_CLASS_NAME_PREFIX, "com.mysql.cj.jdbc.Driver");
+        properties.setProperty(DruidConfig.DB_CONFIG_USERNAME_PREFIX, "username");
+        properties.setProperty(DruidConfig.DB_CONFIG_PASSWORD_PREFIX, "password");
+        // 保存到文件
+        properties.store(new FileOutputStream(configFile), "db config");
+        druidDataSource = druidConfig.initDataSource();
+        assertEquals(properties.getProperty(DruidConfig.DB_CONFIG_URL_PREFIX), druidDataSource.getUrl());
+        assertEquals(properties.getProperty(DruidConfig.DB_CONFIG_DRIVER_CLASS_NAME_PREFIX), druidDataSource.getDriverClassName());
+        assertEquals(properties.getProperty(DruidConfig.DB_CONFIG_USERNAME_PREFIX), druidDataSource.getUsername());
+        assertEquals(properties.getProperty(DruidConfig.DB_CONFIG_PASSWORD_PREFIX), druidDataSource.getPassword());
+    }
+
+    @After
+    public void setConfigBack() {
+        if (bakConfigFile.exists()) {
+            System.out.println("恢复配置文件成功");
+            copyFile(bakConfigFile, configFile);
+            bakConfigFile.deleteOnExit();
+        }
+    }
+
+    @Before
+    public void recordConfig() throws IOException {
+        this.bakConfigFile = new File(DruidConfig.DB_CONFIG_PATH + ".bak");
+        this.configFile = new File(DruidConfig.DB_CONFIG_PATH);
+        if (configFile.exists()) {
+            System.out.println("备份文件成功");
+            copyFile(configFile, bakConfigFile);
+        }
+    }
+
+    /**
+     * 复制文件
+     *
+     * @param src
+     * @param dist
+     * @return
+     */
+    private boolean copyFile(File src, File dist) {
+        try {
+            // 复制备份文件
+            FileOutputStream fos = new FileOutputStream(dist);
+            FileInputStream fis = new FileInputStream(src);
+            int len = 0;
+            byte[] bytes = new byte[1024];
+            while ((len = fis.read(bytes)) != -1) {
+                fos.write(bytes, 0, len);
+            }
+            fos.close();
+            fis.close();
+            return true;
+        } catch (IOException e) {
+            return false;
+        }
+    }
+}