读写分离

背景信息

Java API 形式配置的读写分离可以方便的适用于各种场景，不依赖额外的 jar 包，用户只需要通过 java 代码构造读写分离数据源便可以使用读写分离功能。

参数解释

配置入口

类名称：org.apache.shardingsphere.readwritesplitting.api.ReadwriteSplittingRuleConfiguration

可配置属性：

主从数据源配置

类名称：org.apache.shardingsphere.readwritesplitting.api.rule.ReadwriteSplittingDataSourceRuleConfiguration

可配置属性：

类名称：org.apache.shardingsphere.readwritesplitting.api.strategy.StaticReadwriteSplittingStrategyConfiguration

可配置属性：

类名称：org.apache.shardingsphere.readwritesplitting.api.strategy.DynamicReadwriteSplittingStrategyConfiguration

可配置属性：

算法类型的详情，请参见内置负载均衡算法列表。 查询一致性路由的详情，请参见核心特性：读写分离。

操作步骤

1. 添加读写分离数据源
2. 设置负载均衡算法
3. 使用读写分离数据源

配置示例

public DataSource getDataSource() throws SQLException {
        ReadwriteSplittingDataSourceRuleConfiguration dataSourceConfig = new ReadwriteSplittingDataSourceRuleConfiguration(
                "demo_read_query_ds", new StaticReadwriteSplittingStrategyConfiguration("demo_write_ds",
                Arrays.asList("demo_read_ds_0", "demo_read_ds_1")), null,"demo_weight_lb");
        Properties algorithmProps = new Properties();
        algorithmProps.setProperty("demo_read_ds_0", "2");
        algorithmProps.setProperty("demo_read_ds_1", "1");
        Map<String, AlgorithmConfiguration> algorithmConfigMap = new HashMap<>(1);
        algorithmConfigMap.put("demo_weight_lb", new AlgorithmConfiguration("WEIGHT", algorithmProps));
        ReadwriteSplittingRuleConfiguration ruleConfig = new ReadwriteSplittingRuleConfiguration(Collections.singleton(dataSourceConfig), algorithmConfigMap);
        Properties props = new Properties();
        props.setProperty("sql-show", Boolean.TRUE.toString());
        return ShardingSphereDataSourceFactory.createDataSource(createDataSourceMap(), Collections.singleton(ruleConfig), props);
    }
    private Map<String, DataSource> createDataSourceMap() {
        Map<String, DataSource> result = new HashMap<>(3, 1);
        result.put("demo_write_ds", DataSourceUtil.createDataSource("demo_write_ds"));
        result.put("demo_read_ds_0", DataSourceUtil.createDataSource("demo_read_ds_0"));
        result.put("demo_read_ds_1", DataSourceUtil.createDataSource("demo_read_ds_1"));
        return result;
    }

相关参考

• 核心特性：读写分离
• YAML 配置：读写分离