gaborgsomogyi commented on a change in pull request #29024: URL: https://github.com/apache/spark/pull/29024#discussion_r755788709
########## File path: sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/connection/ConnectionProvider.scala ########## @@ -18,60 +18,45 @@ package org.apache.spark.sql.execution.datasources.jdbc.connection import java.sql.{Connection, Driver} -import java.util.Properties +import java.util.ServiceLoader -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() +import scala.collection.mutable - /** - * Opens connection toward the database. - */ - def getConnection(): Connection -} +import org.apache.spark.internal.Logging +import org.apache.spark.security.SecurityConfigurationLock +import org.apache.spark.sql.jdbc.JdbcConnectionProvider +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) } } + // Seems duplicate but it's needed for Scala 2.13 + providers.toSeq + } + + def create(driver: Driver, options: Map[String, String]): Connection = { + val filteredProviders = providers.filter(_.canHandle(driver, options)) + require(filteredProviders.size == 1, + "JDBC connection initiated but not exactly one connection provider found which can handle " + + s"it. Found active providers: ${filteredProviders.mkString(", ")}") + SecurityConfigurationLock.synchronized { Review comment: @srowen @HyukjinKwon I would like to help here either with code or review but I'm going to have surgery either this or next week so I'm going to be fully off for quite some time. If it's urgent maybe @maropu can help since he's reviewed this code. All in all I would implement something like this: ``` if (provider.wantsToModifySecCtx()) { SecurityConfigurationLock.synchronized { filteredProviders.head.getConnection(driver, options) } } else { filteredProviders.head.getConnection(driver, options) } ``` -- 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. To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org 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