feat: 新增 refresh-datasource-sample

spring-boot-4/pom.xml

@@ -42,6 +42,7 @@
         <module>mybatisplus3-sample</module>
         <module>name-pattern-sample</module>
         <module>quartz-sample</module>
+        <module>refresh-datasource-sample</module>
         <module>shardingsphere-jdbc-5.x-core-sample</module>
         <module>spel-sample</module>
         <module>tx-local-sample</module>

spring-boot-4/refresh-datasource-sample/pom.xml

@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>spring-boot-4-samples</artifactId>
+        <groupId>com.baomidou</groupId>
+        <version>1.0.0</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>refresh-datasource-sample</artifactId>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-jdbc</artifactId>
+        </dependency>
+        <!--仅为演示「spring.datasource.dynamic.refresh-enabled=true」的自动刷新路径：
+            classpath 存在 RefreshEvent 时框架会自动挂上监听器，换成 Nacos/Apollo 只需换这个依赖。-->
+        <dependency>
+            <groupId>org.springframework.cloud</groupId>
+            <artifactId>spring-cloud-context</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.baomidou</groupId>
+            <artifactId>dynamic-datasource-spring-boot4-starter</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+</project>

spring-boot-4/refresh-datasource-sample/src/main/java/com/baomidou/samples/refresh/RefreshDsApplication.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright © ${project.inceptionYear} organization baomidou
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.baomidou.samples.refresh;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+/**
+ * 配置中心刷新数据源示例。
+ *
+ * <p>本示例刻意不连真实的 Nacos：刷新这件事与配置中心无关，换成任何配置中心都只是 「把新配置交给 DynamicDataSourceRefresher」这一步。
+ */
+@Slf4j
+@SpringBootApplication
+public class RefreshDsApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(RefreshDsApplication.class, args);
+        log.info(
+                "try: curl -X POST localhost:8080/datasources/refresh -H 'Content-Type: application/json' "
+                        + "-d '[{\"name\":\"slave_2\",\"url\":\"jdbc:h2:mem:slave2;DB_CLOSE_DELAY=-1\","
+                        + "\"username\":\"sa\",\"password\":\"\",\"driverClassName\":\"org.h2.Driver\"}]'");
+    }
+}

spring-boot-4/refresh-datasource-sample/src/main/java/com/baomidou/samples/refresh/controller/RefreshController.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright © ${project.inceptionYear} organization baomidou
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.baomidou.samples.refresh.controller;
+
+import com.baomidou.dynamic.datasource.DynamicRoutingDataSource;
+import com.baomidou.dynamic.datasource.creator.DataSourceProperty;
+import com.baomidou.dynamic.datasource.spring.boot.autoconfigure.DynamicDataSourceRefresher;
+import com.baomidou.samples.refresh.dto.DataSourceDTO;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import javax.sql.DataSource;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+/**
+ * 数据源刷新入口。
+ *
+ * <p>{@code POST /datasources/refresh} 等价于配置中心推送了一份新配置：把整份数据源清单交给 {@link
+ * DynamicDataSourceRefresher#refresh}，由它做 diff 后只重建变化的连接池。 接入 Spring Cloud 时这一步由框架自带的监听器完成，无需本接口。
+ */
+@RestController
+@RequestMapping("/datasources")
+public class RefreshController {
+
+    private final DataSource dataSource;
+    private final DynamicDataSourceRefresher refresher;
+
+    public RefreshController(DataSource dataSource, DynamicDataSourceRefresher refresher) {
+        this.dataSource = dataSource;
+        this.refresher = refresher;
+    }
+
+    /** 当前所有数据源 */
+    @GetMapping
+    public Set<String> now() {
+        return routing().getDataSources().keySet();
+    }
+
+    /** 用一份新配置刷新数据源，返回本次新增/更新/移除/跳过的明细 */
+    @PostMapping("/refresh")
+    public DynamicDataSourceRefresher.Result refresh(@RequestBody List<DataSourceDTO> config) {
+        Map<String, DataSourceProperty> next = new LinkedHashMap<>();
+        for (DataSourceDTO item : config) {
+            DataSourceProperty property = new DataSourceProperty();
+            property.setUrl(item.getUrl());
+            property.setUsername(item.getUsername());
+            property.setPassword(item.getPassword());
+            property.setDriverClassName(item.getDriverClassName());
+            next.put(item.getName(), property);
+        }
+        return refresher.refresh(next);
+    }
+
+    private DynamicRoutingDataSource routing() {
+        return (DynamicRoutingDataSource) dataSource;
+    }
+}

spring-boot-4/refresh-datasource-sample/src/main/java/com/baomidou/samples/refresh/dto/DataSourceDTO.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright © ${project.inceptionYear} organization baomidou
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.baomidou.samples.refresh.dto;
+
+import lombok.Data;
+
+/** 一份数据源配置，对应配置中心里 {@code spring.datasource.dynamic.datasource.<name>} 的片段。 */
+@Data
+public class DataSourceDTO {
+
+    /** 数据源名称 */
+    private String name;
+
+    /** JDBC url */
+    private String url;
+
+    /** 用户名 */
+    private String username;
+
+    /** 密码 */
+    private String password;
+
+    /** 驱动类名 */
+    private String driverClassName;
+}

spring-boot-4/refresh-datasource-sample/src/main/resources/application.yml

@@ -0,0 +1,23 @@
+server:
+  port: 8080
+
+spring:
+  datasource:
+    dynamic:
+      primary: master
+      strict: true
+      # 替换连接池时等待活跃连接归还，避免刷新把在途请求直接打断
+      grace-destroy: true
+      # classpath 存在 Spring Cloud 的 RefreshEvent 时，配置变更会自动刷新数据源
+      refresh-enabled: true
+      datasource:
+        master:
+          url: jdbc:h2:mem:master;DB_CLOSE_DELAY=-1
+          username: sa
+          password: ''
+          driver-class-name: org.h2.Driver
+        slave_1:
+          url: jdbc:h2:mem:slave1;DB_CLOSE_DELAY=-1
+          username: sa
+          password: ''
+          driver-class-name: org.h2.Driver

spring-boot-4/refresh-datasource-sample/src/test/java/com/baomidou/samples/refresh/test/RefreshDatasourceSampleTest.java

@@ -0,0 +1,85 @@
+/*
+ * Copyright © ${project.inceptionYear} organization baomidou
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.baomidou.samples.refresh.test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.baomidou.dynamic.datasource.DynamicRoutingDataSource;
+import com.baomidou.dynamic.datasource.spring.boot.autoconfigure.DynamicDataSourceRefresher;
+import com.baomidou.samples.refresh.controller.RefreshController;
+import com.baomidou.samples.refresh.dto.DataSourceDTO;
+import java.util.ArrayList;
+import java.util.List;
+import javax.sql.DataSource;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class RefreshDatasourceSampleTest {
+
+    @Autowired private RefreshController controller;
+
+    @Autowired private DataSource dataSource;
+
+    @Test
+    void shouldAddAndRemoveDataSourceByRefresh() {
+        DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource;
+        assertThat(ds.getDataSources())
+                .containsKeys("master", "slave_1")
+                .doesNotContainKey("slave_2");
+
+        List<DataSourceDTO> withNewOne = new ArrayList<>(initialConfig());
+        withNewOne.add(h2("slave_2", "jdbc:h2:mem:slave2;DB_CLOSE_DELAY=-1"));
+
+        DynamicDataSourceRefresher.Result added = controller.refresh(withNewOne);
+        assertThat(added.getAdded()).containsExactly("slave_2");
+        assertThat(ds.getDataSources()).containsKey("slave_2");
+
+        DynamicDataSourceRefresher.Result removed = controller.refresh(initialConfig());
+        assertThat(removed.getRemoved()).containsExactly("slave_2");
+        assertThat(ds.getDataSources()).doesNotContainKey("slave_2");
+    }
+
+    @Test
+    void shouldSkipWhenConfigUnchanged() {
+        DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource;
+        DataSource slaveBefore = ds.getDataSources().get("slave_1");
+
+        DynamicDataSourceRefresher.Result result = controller.refresh(initialConfig());
+
+        assertThat(result.isChanged()).isFalse();
+        assertThat(result.getSkipped()).contains("master", "slave_1");
+        assertThat(ds.getDataSources().get("slave_1")).isSameAs(slaveBefore);
+    }
+
+    private static List<DataSourceDTO> initialConfig() {
+        List<DataSourceDTO> config = new ArrayList<>();
+        config.add(h2("master", "jdbc:h2:mem:master;DB_CLOSE_DELAY=-1"));
+        config.add(h2("slave_1", "jdbc:h2:mem:slave1;DB_CLOSE_DELAY=-1"));
+        return config;
+    }
+
+    private static DataSourceDTO h2(String name, String url) {
+        DataSourceDTO dto = new DataSourceDTO();
+        dto.setName(name);
+        dto.setUrl(url);
+        dto.setUsername("sa");
+        dto.setPassword("");
+        dto.setDriverClassName("org.h2.Driver");
+        return dto;
+    }
+}