greyp9 commented on a change in pull request #5617: URL: https://github.com/apache/nifi/pull/5617#discussion_r772743091
########## File path: nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/ssh/StandardSSHConfigProvider.java ########## @@ -0,0 +1,133 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.nifi.processors.standard.ssh; + +import net.schmizz.keepalive.KeepAlive; +import net.schmizz.keepalive.KeepAliveProvider; +import net.schmizz.sshj.Config; +import net.schmizz.sshj.DefaultConfig; +import net.schmizz.sshj.common.Factory; +import net.schmizz.sshj.connection.ConnectionImpl; + +import org.apache.nifi.components.PropertyDescriptor; +import org.apache.nifi.components.PropertyValue; +import org.apache.nifi.context.PropertyContext; + +import java.util.Arrays; +import java.util.List; +import java.util.Optional; +import java.util.Set; +import java.util.stream.Collectors; + +import static org.apache.nifi.processors.standard.util.SFTPTransfer.KEY_EXCHANGE_ALGORITHMS_ALLOWED; +import static org.apache.nifi.processors.standard.util.SFTPTransfer.CIPHERS_ALLOWED; +import static org.apache.nifi.processors.standard.util.SFTPTransfer.KEY_ALGORITHMS_ALLOWED; +import static org.apache.nifi.processors.standard.util.SFTPTransfer.MESSAGE_AUTHENTICATION_CODES_ALLOWED; +import static org.apache.nifi.processors.standard.util.SFTPTransfer.USE_KEEPALIVE_ON_TIMEOUT; + +/** + * Standard implementation of SSH Configuration Provider + */ +public class StandardSSHConfigProvider implements SSHConfigProvider { + private static final String COMMA_SEPARATOR = ","; + + private static final int KEEP_ALIVE_INTERVAL_SECONDS = 5; + + private static final KeepAliveProvider DISABLED_KEEP_ALIVE_PROVIDER = new DisabledKeepAliveProvider(); + + /** + * Get SSH configuration based on configured properties + * + * @param identifier SSH Client identifier for runtime tracking + * @param context Property Context + * @return SSH Configuration + */ + @Override + public Config getConfig(final String identifier, final PropertyContext context) { + final DefaultConfig config = new DefaultConfig(); + final KeepAliveProvider keepAliveProvider = getKeepAliveProvider(identifier, context); + config.setKeepAliveProvider(keepAliveProvider); + + getOptionalProperty(context, CIPHERS_ALLOWED).ifPresent(property -> config.setCipherFactories(getFilteredValues(property, config.getCipherFactories()))); + getOptionalProperty(context, KEY_ALGORITHMS_ALLOWED).ifPresent(property -> config.setKeyAlgorithms(getFilteredValues(property, config.getKeyAlgorithms()))); + getOptionalProperty(context, KEY_EXCHANGE_ALGORITHMS_ALLOWED).ifPresent(property -> config.setKeyExchangeFactories(getFilteredValues(property, config.getKeyExchangeFactories()))); + getOptionalProperty(context, MESSAGE_AUTHENTICATION_CODES_ALLOWED).ifPresent(property -> config.setMACFactories(getFilteredValues(property, config.getMACFactories()))); + + return config; + } + + private Optional<String> getOptionalProperty(final PropertyContext context, final PropertyDescriptor propertyDescriptor) { + final PropertyValue propertyValue = context.getProperty(propertyDescriptor); + return propertyValue.isSet() ? Optional.of(propertyValue.evaluateAttributeExpressions().getValue()) : Optional.empty(); + } + + private <T> List<Factory.Named<T>> getFilteredValues(final String propertyValue, final List<Factory.Named<T>> supportedValues) { + final Set<String> configuredValues = getCommaSeparatedValues(propertyValue); + return supportedValues.stream().filter(named -> configuredValues.contains(named.getName())).collect(Collectors.toList()); + } + + private Set<String> getCommaSeparatedValues(final String propertyValue) { + final String[] values = propertyValue.split(COMMA_SEPARATOR); + return Arrays.stream(values).map(String::trim).collect(Collectors.toSet()); + } + + private KeepAliveProvider getKeepAliveProvider(final String identifier, final PropertyContext context) { + final boolean keepAliveEnabled = context.getProperty(USE_KEEPALIVE_ON_TIMEOUT).asBoolean(); + return keepAliveEnabled ? new EnabledKeepAliveProvider(identifier) : DISABLED_KEEP_ALIVE_PROVIDER; + } + + private static class EnabledKeepAliveProvider extends KeepAliveProvider { + private final String identifier; + + private EnabledKeepAliveProvider(final String identifier) { + this.identifier = identifier; + } + + @Override + public KeepAlive provide(final ConnectionImpl connection) { + final KeepAlive keepAlive = KeepAliveProvider.KEEP_ALIVE.provide(connection); + keepAlive.setName(String.format("SSH-keep-alive-%s", identifier)); Review comment: Too bad we don't have a way of passing through the processor id. Although, I guess we won't need it now. :) -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
