很多业务场景，业务功能必须用pg数据库，这时候注册中心如果用mysql的话，显得浪费资源，基于此，nacos源码修改持久化到postgreSQL数据库是一个必然需求，此处我们修改为只支持pg数据库，2.4版本的源码。

源码拉取和编译参考：前置内容

1、修改配置文件

修改console和nacos-distribution模块中的application.properties配置文件，内容如下：

spring.sql.init.platform=postgresql
db.num=1
db.url.0=jdbc:postgresql://14.xx.78.188:5432/nacos
db.user.0=postgres
db.password.0=123456

2、修改pom文件

#nacos-all中添加依赖
<dependency>
    <groupId>org.postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <version>42.2.18</version>
</dependency>

#naming模块中添加依赖：
<dependency>
    <groupId>org.postgresql</groupId>
    <artifactId>postgresql</artifactId>
</dependency>

#config模块中添加依赖：
<dependency>
    <groupId>org.postgresql</groupId>
    <artifactId>postgresql</artifactId>
</dependency>

3、修改驱动加载相关类

ExternalDataSourceProperties.java 中的方法修改为：

private static final String JDBC_DRIVER_NAME = "org.postgresql.Driver";

List<HikariDataSource> build(Environment environment, Callback<HikariDataSource> callback) {
        List<HikariDataSource> dataSources = new ArrayList<>();
        Binder.get(environment).bind("db", Bindable.ofInstance(this));
        Preconditions.checkArgument(Objects.nonNull(num), "db.num is null");
        Preconditions.checkArgument(CollectionUtils.isNotEmpty(user), "db.user or db.user.[index] is null");
        Preconditions.checkArgument(CollectionUtils.isNotEmpty(password), "db.password or db.password.[index] is null");
        for (int index = 0; index < num; index++) {
            int currentSize = index + 1;
            Preconditions.checkArgument(url.size() >= currentSize, "db.url.%s is null", index);
            DataSourcePoolProperties poolProperties = DataSourcePoolProperties.build(environment);
            //修改如下
            if (StringUtils.isEmpty(poolProperties.getDataSource().getDriverClassName())) {
                String driverClassName = JDBC_DRIVER_NAME;
                if ("postgresql".equals(EnvUtil.getProperty("spring.datasource.platform"))) {
                    driverClassName = "org.postgresql.Driver";
                    poolProperties.setDriverClassName(driverClassName);
                }
            }
            poolProperties.setJdbcUrl(url.get(index).trim());
            poolProperties.setUsername(getOrDefault(user, index, user.get(0)).trim());
            poolProperties.setPassword(getOrDefault(password, index, password.get(0)).trim());
            HikariDataSource ds = poolProperties.getDataSource();
            if (StringUtils.isEmpty(ds.getConnectionTestQuery())) {
                ds.setConnectionTestQuery(TEST_QUERY);
            }
            
            dataSources.add(ds);
            callback.accept(ds);
        }
        Preconditions.checkArgument(CollectionUtils.isNotEmpty(dataSources), "no datasource available");
        return dataSources;
    }

ExternalDataSourceServiceImpl.java 和 

LocalDataSourceServiceImpl.java 类中修改：

private String dataSourceType = "postgresql";

 

4、配置中心数据加载配置

MapperManager.java 类中方法的修改

public <R extends Mapper> R findMapper(String dataSource, String tableName) {
        if (LOGGER.isDebugEnabled()) {
            LOGGER.debug("[MapperManager] findMapper dataSource: {}, tableName: {}", dataSource, tableName);
        }
        if (StringUtils.isBlank(dataSource) || StringUtils.isBlank(tableName)) {
            throw new NacosRuntimeException(FIND_DATASOURCE_ERROR_CODE, "dataSource or tableName is null");
        }
        Map<String, Mapper> mysql = MAPPER_SPI_MAP.get("mysql");
        MAPPER_SPI_MAP.put("postgresql", mysql);//添加pg数据库注册中心的表结构
        Map<String, Mapper> tableMapper = MAPPER_SPI_MAP.get(dataSource);
        if (Objects.isNull(tableMapper)) {
            throw new NacosRuntimeException(FIND_DATASOURCE_ERROR_CODE,
                    "[MapperManager] Failed to find the datasource,dataSource:" + dataSource);
        }
        Mapper mapper = tableMapper.get(tableName);
        if (Objects.isNull(mapper)) {
            throw new NacosRuntimeException(FIND_TABLE_ERROR_CODE,
                    "[MapperManager] Failed to find the table ,tableName:" + tableName);
        }
        if (dataSourceLogEnable) {
            return MapperProxy.createSingleProxy(mapper);
        }
        return (R) mapper;
    }

5、所有limit ?,? 替换为 offset ? limit ? 以支持pg

WhereBuilder.java中修改：

    public WhereBuilder limit(int startRow, int pageSize) {
        where.append(" OFFSET ")
                .append(startRow)
                .append(" LIMIT ")//注意要有空格
                .append(pageSize);
        return this;
    }

另外，修改mysql目录下的文件：

 举例：ConfigInfoMapperByMySql.java 

   @Override
    public MapperResult findConfigInfoByAppFetchRows(MapperContext context) {
        final String appName = (String) context.getWhereParameter(FieldConstant.APP_NAME);
        final String tenantId = (String) context.getWhereParameter(FieldConstant.TENANT_ID);
        String sql = "SELECT id,data_id,group_id,tenant_id,app_name,content FROM config_info"
                + " WHERE tenant_id LIKE ? AND app_name= ?" + " OFFSET " + context.getStartRow() + " LIMIT "
                + context.getPageSize();
        return new MapperResult(sql, CollectionUtils.list(tenantId, appName));
    }

其他类依次修改完成即可。 

注意： LIMIT 左右要有空格！

6、nacos 表结构导入pg

方案一：通过navicat 15以上版本，工具--数据传输，把mysql数据库中nacos的表结构和数据导入到pg库中：

成功之后，再pg库添加主键序列，比如：

CREATE SEQUENCE config_info_id_seq START WITH 1;
ALTER TABLE config_info ALTER COLUMN id SET DEFAULT nextval('config_info_id_seq');

CREATE SEQUENCE config_info_aggr_id_seq START WITH 18;
ALTER TABLE config_info_aggr ALTER COLUMN id SET DEFAULT nextval('config_info_aggr_id_seq');

CREATE SEQUENCE config_info_tag_id_seq START WITH 18;
ALTER TABLE config_info_tag ALTER COLUMN id SET DEFAULT nextval('config_info_tag_id_seq');

CREATE SEQUENCE config_tags_relation_id_seq START WITH 18;
ALTER TABLE config_tags_relation ALTER COLUMN id SET DEFAULT nextval('config_tags_relation_id_seq');

CREATE SEQUENCE group_capacity_id_seq START WITH 18;
ALTER TABLE group_capacity ALTER COLUMN id SET DEFAULT nextval('group_capacity_id_seq');

CREATE SEQUENCE his_config_info_nid_seq START WITH 1;
ALTER TABLE his_config_info ALTER COLUMN id SET DEFAULT nextval('his_config_info_nid_seq');

CREATE SEQUENCE permissions_id_seq START WITH 18;
ALTER TABLE permissions ALTER COLUMN id SET DEFAULT nextval('permissions_id_seq');

CREATE SEQUENCE roles_id_seq START WITH 18;
ALTER TABLE roles ALTER COLUMN id SET DEFAULT nextval('roles_id_seq');

CREATE SEQUENCE tenant_capacity_id_seq START WITH 18;
ALTER TABLE tenant_capacity ALTER COLUMN id SET DEFAULT nextval('tenant_capacity_id_seq');

CREATE SEQUENCE tenant_info_id_seq START WITH 18;
ALTER TABLE tenant_info ALTER COLUMN id SET DEFAULT nextval('tenant_info_id_seq');

数据不全，可以自行补充序列。

7、修改后的源码编译打包

         mvn -Prelease-nacos clean install -U -DskipTests

打包成功

 

8、应用程序启动nacos

nacos-distribution 目录下找到 nacos-server-2.4.2.zip 文件

此包解压缩在win或者Linux环境 就可以启动了，比如在win环境启动：在bin目录下创建执行脚本

yd-startup.bat

startup.cmd -m standalone

其实执行命令也行。 此时访问 http://localhost:8848/nacos/ 没有进入登录页面，即没有鉴权，不安全，如果需要鉴权关闭服务，修改配置。

9、开启鉴权配置

修改console和nacos-distribution模块中的application.properties配置文件

### If turn on auth system: 修改
nacos.core.auth.enabled=true

### Turn on/off caching of auth information. By turning on this switch, the update of auth information would have a 15 seconds delay.
nacos.core.auth.caching.enabled=true

### Since 1.4.1, Turn on/off white auth for user-agent: nacos-server, only for upgrade from old version. 修改
nacos.core.auth.enable.userAgentAuthWhite=true

### Since 1.4.1, worked when nacos.core.auth.enabled=true and nacos.core.auth.enable.userAgentAuthWhite=false.
### The two properties is the white list for auth and used by identity the request from other server.修改
nacos.core.auth.server.identity.key=nacos
nacos.core.auth.server.identity.value=nacos

### worked when nacos.core.auth.system.type=nacos
### The token expiration in seconds:
nacos.core.auth.plugin.nacos.token.cache.enable=false
nacos.core.auth.plugin.nacos.token.expire.seconds=18000
### The default token (Base64 string):放开
nacos.core.auth.plugin.nacos.token.secret.key=SecretKey012345678901234567890123678901234567890123456789
#nacos.core.auth.plugin.nacos.token.secret.key=

然后再启动后就进入登录页面。

10、用户表结构修改

创建用户时失败：

原因是：代码里标识参数是bool类型，而数据库表结构里是int2类型，说明是数据表结构传输过程出错了，

 

修改方案sql：

ALTER TABLE users
ALTER COLUMN enabled 
TYPE BOOLEAN 
USING CASE 
    WHEN enabled = 1 THEN TRUE 
    ELSE FALSE 
END;

到此，nacos源码修改持久化到postgreSQL数据库分享完成，当然持久到pg还有其他方案，后期可以分享nacos同时支持多种数据库，敬请期待！