Readwrite-splitting

Background

The read/write splitting configured in Java API form can be easily applied to various scenarios without relying on additional jar packages. Users only need to construct the read/write splitting data source through java code to be able to use the read/write splitting function.

Parameters Explained

Entry

Class name: org.apache.shardingsphere.readwritesplitting.api.ReadwriteSplittingRuleConfiguration

Configurable Properties:

NameDataTypeDescription
dataSources (+)Collection<ReadwriteSplittingDataSourceRuleConfiguration>Data sources of write and reads
loadBalancers (*)Map<String, AlgorithmConfiguration>Load balance algorithm name and configurations of replica data sources

Primary-secondary Data Source Configuration

Class name: org.apache.shardingsphere.readwritesplitting.api.rule.ReadwriteSplittingDataSourceRuleConfiguration

Configurable Properties:

NameDataTypeDescriptionDefault Value
nameStringReadwrite-splitting data source name-
writeDataSourceNameStringWrite data source name-
readDataSourceNamesList<String>Read data sources list-
transactionalReadQueryStrategy (?)TransactionalReadQueryStrategyRouting strategy for read query within a transaction, values include: PRIMARY (to primary), FIXED (to fixed data source), DYNAMIC (to any data source)DYNAMIC
loadBalancerName (?)StringLoad balance algorithm name of replica sourcesRound robin load balance algorithm

Please refer to Built-in Load Balance Algorithm List for details on algorithm types.

Operating Procedures

  1. Add read-write splitting data source
  2. Set load balancing algorithms
  3. Use read-write splitting data source

Configuration Examples

  1. public DataSource getDataSource() throws SQLException {
  2.         ReadwriteSplittingDataSourceRuleConfiguration dataSourceConfig = new ReadwriteSplittingDataSourceRuleConfiguration(
  3.                 "demo_read_query_ds", "demo_write_ds", Arrays.asList("demo_read_ds_0", "demo_read_ds_1"), "demo_weight_lb");
  4.         Properties algorithmProps = new Properties();
  5.         algorithmProps.setProperty("demo_read_ds_0", "2");
  6.         algorithmProps.setProperty("demo_read_ds_1", "1");
  7.         Map<String, AlgorithmConfiguration> algorithmConfigMap = new HashMap<>(1);
  8.         algorithmConfigMap.put("demo_weight_lb", new AlgorithmConfiguration("WEIGHT", algorithmProps));
  9.         ReadwriteSplittingRuleConfiguration ruleConfig = new ReadwriteSplittingRuleConfiguration(Collections.singleton(dataSourceConfig), algorithmConfigMap);
  10.         Properties props = new Properties();
  11.         props.setProperty("sql-show", Boolean.TRUE.toString());
  12.         return ShardingSphereDataSourceFactory.createDataSource(createDataSourceMap(), Collections.singleton(ruleConfig), props);
  13.     }
  15.     private Map<String, DataSource> createDataSourceMap() {
  16.         Map<String, DataSource> result = new HashMap<>(3, 1);
  17.         result.put("demo_write_ds", DataSourceUtil.createDataSource("demo_write_ds"));
  18.         result.put("demo_read_ds_0", DataSourceUtil.createDataSource("demo_read_ds_0"));
  19.         result.put("demo_read_ds_1", DataSourceUtil.createDataSource("demo_read_ds_1"));
  20.         return result;
  21.     }

References