viirya commented on a change in pull request #29024: URL: https://github.com/apache/spark/pull/29024#discussion_r495488559
########## File path: sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/connection/ConnectionProvider.scala ########## @@ -18,60 +18,41 @@ package org.apache.spark.sql.execution.datasources.jdbc.connection import java.sql.{Connection, Driver} -import java.util.Properties +import java.util.ServiceLoader + +import scala.collection.mutable import org.apache.spark.internal.Logging import org.apache.spark.sql.execution.datasources.jdbc.JDBCOptions - -/** - * Connection provider which opens connection toward various databases (database specific instance - * needed). If kerberos authentication required then it's the provider's responsibility to set all - * the parameters. - */ -private[jdbc] trait ConnectionProvider { - /** - * Additional properties for data connection (Data source property takes precedence). - */ - def getAdditionalProperties(): Properties = new Properties() - - /** - * Opens connection toward the database. - */ - def getConnection(): Connection -} +import org.apache.spark.util.Utils private[jdbc] object ConnectionProvider extends Logging { - def create(driver: Driver, options: JDBCOptions): ConnectionProvider = { - if (options.keytab == null || options.principal == null) { - logDebug("No authentication configuration found, using basic connection provider") - new BasicConnectionProvider(driver, options) - } else { - logDebug("Authentication configuration found, using database specific connection provider") - options.driverClass match { - case PostgresConnectionProvider.driverClass => - logDebug("Postgres connection provider found") - new PostgresConnectionProvider(driver, options) - - case MariaDBConnectionProvider.driverClass => - logDebug("MariaDB connection provider found") - new MariaDBConnectionProvider(driver, options) - - case DB2ConnectionProvider.driverClass => - logDebug("DB2 connection provider found") - new DB2ConnectionProvider(driver, options) - - case MSSQLConnectionProvider.driverClass => - logDebug("MS SQL connection provider found") - new MSSQLConnectionProvider(driver, options) - - case OracleConnectionProvider.driverClass => - logDebug("Oracle connection provider found") - new OracleConnectionProvider(driver, options) - - case _ => - throw new IllegalArgumentException(s"Driver ${options.driverClass} does not support " + - "Kerberos authentication") + private val providers = loadProviders() + + def loadProviders(): Seq[JdbcConnectionProvider] = { + val loader = ServiceLoader.load(classOf[JdbcConnectionProvider], + Utils.getContextOrSparkClassLoader) + val providers = mutable.ArrayBuffer[JdbcConnectionProvider]() + + val iterator = loader.iterator + while (iterator.hasNext) { + try { + val provider = iterator.next + logDebug(s"Loaded built in provider: $provider") + providers += provider + } catch { + case t: Throwable => + logError(s"Failed to load built in provider.", t) } } + providers + } + + def create(driver: Driver, options: JDBCOptions): Connection = { + val filteredProviders = providers.filter(_.canHandle(driver, options)) + logDebug(s"Filtered providers: $filteredProviders") + require(filteredProviders.size == 1, + "JDBC connection initiated but not exactly one connection provider found which can handle it") Review comment: Could you also show up in the err message what connect providers are found for the driver? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org