ComboPooledDataSource not compatible with apache shardingsphere

[silversteak]

ComboPooledDataSource not compatible with apache shardingsphere.

I am currently trying to implement shardingshpere in my current company's codebase. Previously created an example project using HikariDataSource and it worked fine.

Now in companies code base uses c3p0.ComboPooledDataSource as datasource. So when am trying to create shardingshphere datasource using this datasource its failing.

In HikariDatasource, the standardProps are coming correct.

But in c3p0.ComboPooledDataSource, the standardProps are giving just password only.

The main cause of the issue is that in c3p0.ComboPooledDataSource, the properties are stored in different format. Like username as user and url as jdbcUrl.

Thats why am getting a nullpointer exception here since both the keys are username and url

I was under the assumption that apache shardingsphere is compatible with all kinds of datasource. I am stuck here.

Please help me out if possible.

Datasource Config

dataSources:
  ds:
    dataSourceClassName: com.mchange.v2.c3p0.ComboPooledDataSource
    driverClassName: com.mysql.jdbc.Driver
    jdbcUrl: jdbc:mysql://localhost:3306/demo_ds?serverTimezone=UTC&useSSL=false&useUnicode=true&characterEncoding=UTF-8
    user: root
    username: root
    password: password
    max-active: 16

pom.xml

<dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>shardingsphere-jdbc-core</artifactId>
            <version>5.1.2</version>
</dependency>
<dependency>
                <groupId>com.mchange</groupId>
                <artifactId>c3p0</artifactId>
                <version>0.9.5.1</version>
</dependency>

[TeslaCN]

Hi @silversteak
Thanks for your feedback. I'm going to check this.

[TeslaCN]

I've reproduced this issue.

[INFO ] 2022-07-29 13:15:56,294 --main-- [com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource] Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 3, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> z8kfsxaqk30d5911hdcsh|47d9a273, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> null, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceSynchronousCheckins -> false, forceUseNamedDriverClass -> false, identityToken -> z8kfsxaqk30d5911hdcsh|47d9a273, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/demo_ds_1?serverTimezone=UTC&useSSL=false&useUnicode=true&characterEncoding=UTF-8&allowPublicKeyRetrieval=true, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 15, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 3, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {password=******, user=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ] 
[INFO ] 2022-07-29 13:15:56,319 --main-- [com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource] Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 3, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, contextClassLoaderSource -> caller, dataSourceName -> z8kfsxaqk30d5911hdcsh|68dc098b, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> null, extensions -> {}, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, forceSynchronousCheckins -> false, forceUseNamedDriverClass -> false, identityToken -> z8kfsxaqk30d5911hdcsh|68dc098b, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/demo_ds_0?serverTimezone=UTC&useSSL=false&useUnicode=true&characterEncoding=UTF-8&allowPublicKeyRetrieval=true, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 15, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 3, numHelperThreads -> 3, preferredTestQuery -> null, privilegeSpawnedThreads -> false, properties -> {password=******, user=******}, propertyCycle -> 0, statementCacheNumDeferredCloseThreads -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, userOverrides -> {}, usesTraditionalReflectiveProxies -> false ] 
Exception in thread "main" java.lang.NullPointerException: Cannot invoke "Object.toString()" because the return value of "java.util.Map.get(Object)" is null
	at org.apache.shardingsphere.infra.metadata.database.resource.ShardingSphereResource.createDataSourceMetaDataMap(ShardingSphereResource.java:63)
	at org.apache.shardingsphere.infra.metadata.database.resource.ShardingSphereResource.<init>(ShardingSphereResource.java:52)
	at org.apache.shardingsphere.infra.metadata.database.ShardingSphereDatabase.createResource(ShardingSphereDatabase.java:115)
	at org.apache.shardingsphere.infra.metadata.database.ShardingSphereDatabase.create(ShardingSphereDatabase.java:109)
	at org.apache.shardingsphere.infra.metadata.database.ShardingSphereDatabase.create(ShardingSphereDatabase.java:91)
	at org.apache.shardingsphere.infra.metadata.database.ShardingSphereDatabasesFactory.createGenericDatabases(ShardingSphereDatabasesFactory.java:80)
	at org.apache.shardingsphere.infra.metadata.database.ShardingSphereDatabasesFactory.create(ShardingSphereDatabasesFactory.java:68)
	at org.apache.shardingsphere.mode.metadata.MetaDataContextsFactory.create(MetaDataContextsFactory.java:66)
	at org.apache.shardingsphere.mode.manager.standalone.StandaloneContextManagerBuilder.build(StandaloneContextManagerBuilder.java:51)
	at org.apache.shardingsphere.driver.jdbc.core.datasource.ShardingSphereDataSource.createContextManager(ShardingSphereDataSource.java:74)
	at org.apache.shardingsphere.driver.jdbc.core.datasource.ShardingSphereDataSource.<init>(ShardingSphereDataSource.java:64)
	at org.apache.shardingsphere.driver.api.ShardingSphereDataSourceFactory.createDataSource(ShardingSphereDataSourceFactory.java:93)
	at org.apache.shardingsphere.driver.api.yaml.YamlShardingSphereDataSourceFactory.createDataSource(YamlShardingSphereDataSourceFactory.java:133)
	at org.apache.shardingsphere.driver.api.yaml.YamlShardingSphereDataSourceFactory.createDataSource(YamlShardingSphereDataSourceFactory.java:62)
	at org.apache.shardingsphere.example.sharding.raw.jdbc.factory.YamlDataSourceFactory.newInstance(YamlDataSourceFactory.java:33)
	at org.apache.shardingsphere.example.sharding.raw.jdbc.ShardingRawYamlConfigurationExample.main(ShardingRawYamlConfigurationExample.java:41)

[TeslaCN]

This could be fixed by implementing DataSourcePoolMetaData for c3p0, just like what we did for HikariCP and DBCP.

https://github.com/apache/shardingsphere/tree/master/shardingsphere-infra/shardingsphere-infra-common/src/main/java/org/apache/shardingsphere/infra/datasource/pool/metadata/type

[TeslaCN]

Hi @silversteak
Are you interested in fixing this?

[silversteak]

Hi @TeslaCN Yes am interested in fixing it. I will provide it soon

[silversteak]

#19947

@TeslaCN Please review the PR.