Examples with SqlDropFunction org.apache.drill.exec.planner.sql.parser.SqlDropFunction used on opensource projects

Example 1 with SqlDropFunction

use of org.apache.drill.exec.planner.sql.parser.SqlDropFunction in project drill by apache.

the class DropFunctionHandler method getPlan.

/**
   * Unregisters UDFs dynamically. Process consists of several steps:
   * <ol>
   * <li>Registering jar in jar registry to ensure that several jars with the same name is not being unregistered.</li>
   * <li>Starts remote unregistration process, gets list of all jars and excludes jar to be deleted.</li>
   * <li>Signals drill bits to start local unregistration process.</li>
   * <li>Removes source and binary jars from registry area.</li>
   * </ol>
   *
   * UDFs unregistration is allowed only if dynamic UDFs support is enabled.
   * Only jars registered dynamically can be unregistered,
   * built-in functions loaded at start up are not allowed to be unregistered.
   *
   * Limitation: before jar unregistration make sure no one is using functions from this jar.
   * There is no guarantee that running queries will finish successfully or give correct result.
   *
   * @return - Single row indicating list of unregistered UDFs, raise exception otherwise
   */
@Override
public PhysicalPlan getPlan(SqlNode sqlNode) throws ForemanSetupException, IOException {
    if (!context.getOption(ExecConstants.DYNAMIC_UDF_SUPPORT_ENABLED).bool_val) {
        throw UserException.validationError().message("Dynamic UDFs support is disabled.").build(logger);
    }
    SqlDropFunction node = unwrap(sqlNode, SqlDropFunction.class);
    String jarName = ((SqlCharStringLiteral) node.getJar()).toValue();
    RemoteFunctionRegistry remoteFunctionRegistry = context.getRemoteFunctionRegistry();
    boolean inProgress = false;
    try {
        final String action = remoteFunctionRegistry.addToJars(jarName, RemoteFunctionRegistry.Action.UNREGISTRATION);
        if (!(inProgress = action == null)) {
            return DirectPlan.createDirectPlan(context, false, String.format("Jar with %s name is used. Action: %s", jarName, action));
        }
        Jar deletedJar = unregister(jarName, remoteFunctionRegistry);
        if (deletedJar == null) {
            return DirectPlan.createDirectPlan(context, false, String.format("Jar %s is not registered in remote registry", jarName));
        }
        remoteFunctionRegistry.submitForUnregistration(jarName);
        removeJarFromArea(jarName, remoteFunctionRegistry.getFs(), remoteFunctionRegistry.getRegistryArea());
        removeJarFromArea(JarUtil.getSourceName(jarName), remoteFunctionRegistry.getFs(), remoteFunctionRegistry.getRegistryArea());
        return DirectPlan.createDirectPlan(context, true, String.format("The following UDFs in jar %s have been unregistered:\n%s", jarName, deletedJar.getFunctionSignatureList()));
    } catch (Exception e) {
        logger.error("Error during UDF unregistration", e);
        return DirectPlan.createDirectPlan(context, false, e.getMessage());
    } finally {
        if (inProgress) {
            remoteFunctionRegistry.finishUnregistration(jarName);
            remoteFunctionRegistry.removeFromJars(jarName);
        }
    }
}