NIFI-13372 Add processor DeleteSFTP

Signed-off-by: Pierre Villard <[email protected]>

This closes #9012.

nifi-extension-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/DeleteSFTP.java

@@ -0,0 +1,221 @@
+/*
+ * 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;
+
+import org.apache.nifi.annotation.behavior.DefaultRunDuration;
+import org.apache.nifi.annotation.behavior.InputRequirement;
+import org.apache.nifi.annotation.behavior.SupportsBatching;
+import org.apache.nifi.annotation.documentation.CapabilityDescription;
+import org.apache.nifi.annotation.documentation.Tags;
+import org.apache.nifi.annotation.documentation.UseCase;
+import org.apache.nifi.components.PropertyDescriptor;
+import org.apache.nifi.components.ValidationContext;
+import org.apache.nifi.components.ValidationResult;
+import org.apache.nifi.expression.ExpressionLanguageScope;
+import org.apache.nifi.flowfile.FlowFile;
+import org.apache.nifi.flowfile.attributes.CoreAttributes;
+import org.apache.nifi.logging.ComponentLog;
+import org.apache.nifi.processor.AbstractProcessor;
+import org.apache.nifi.processor.ProcessContext;
+import org.apache.nifi.processor.ProcessSession;
+import org.apache.nifi.processor.Relationship;
+import org.apache.nifi.processor.exception.FlowFileAccessException;
+import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.processor.util.StandardValidators;
+import org.apache.nifi.processor.util.file.transfer.FileTransfer;
+import org.apache.nifi.processors.standard.util.FTPTransfer;
+import org.apache.nifi.processors.standard.util.SFTPTransfer;
+
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.TimeUnit;
+
+@SupportsBatching(defaultDuration = DefaultRunDuration.TWENTY_FIVE_MILLIS)
+@InputRequirement(InputRequirement.Requirement.INPUT_REQUIRED)
+@Tags({"remote", "remove", "delete", "sftp"})
+@CapabilityDescription("Deletes a file residing on an SFTP server.")
+@UseCase(
+        description = "Delete source file only after its processing completed",
+        configuration = """
+                Retrieve a file residing on an SFTP server, e.g. using 'ListSFTP' and 'FetchSFTP'.
+                Process the file using any combination of processors.
+                Store the resulting file to a destination, e.g. using 'PutFile'.
+                Using 'DeleteSFTP', delete the file residing on an SFTP server only after the result has been stored.
+                """
+)
+public class DeleteSFTP extends AbstractProcessor {
+
+    public static final Relationship REL_SUCCESS = new Relationship.Builder()
+            .name("success")
+            .description("All FlowFiles, for which an existing file has been deleted, are routed to this relationship")
+            .build();
+    public static final Relationship REL_NOT_FOUND = new Relationship.Builder()
+            .name("not found")
+            .description("All FlowFiles, for which the file to delete did not exist, are routed to this relationship")
+            .build();
+    public static final Relationship REL_FAILURE = new Relationship.Builder()
+            .name("failure")
+            .description("All FlowFiles, for which an existing file could not be deleted, are routed to this relationship")
+            .build();
+
+    private final static Set<Relationship> relationships = Set.of(REL_SUCCESS, REL_NOT_FOUND, REL_FAILURE);
+
+    public static final PropertyDescriptor DIRECTORY_PATH = new PropertyDescriptor.Builder()
+            .name("Directory Path")
+            .displayName("Directory Path")
+            .description("The path to the directory the file to delete is located in.")
+            .required(true)
+            .defaultValue("${" + CoreAttributes.PATH.key() + "}")
+            .addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
+            .expressionLanguageSupported(ExpressionLanguageScope.FLOWFILE_ATTRIBUTES)
+            .build();
+    public static final PropertyDescriptor FILENAME = new PropertyDescriptor.Builder()
+            .name("Filename")
+            .displayName("Filename")
+            .description("The name of the file to delete.")
+            .required(true)
+            .defaultValue("${" + CoreAttributes.FILENAME.key() + "}")
+            .addValidator(StandardValidators.NON_EMPTY_EL_VALIDATOR)
+            .expressionLanguageSupported(ExpressionLanguageScope.FLOWFILE_ATTRIBUTES)
+            .build();
+
+    private final static List<PropertyDescriptor> properties = List.of(
+            DIRECTORY_PATH,
+            FILENAME,
+            SFTPTransfer.HOSTNAME,
+            SFTPTransfer.PORT,
+            SFTPTransfer.USERNAME,
+            SFTPTransfer.PASSWORD,
+            SFTPTransfer.PRIVATE_KEY_PATH,
+            SFTPTransfer.PRIVATE_KEY_PASSPHRASE,
+            SFTPTransfer.STRICT_HOST_KEY_CHECKING,
+            SFTPTransfer.HOST_KEY_FILE,
+            SFTPTransfer.BATCH_SIZE,
+            SFTPTransfer.CONNECTION_TIMEOUT,
+            SFTPTransfer.DATA_TIMEOUT,
+            SFTPTransfer.USE_KEEPALIVE_ON_TIMEOUT,
+            SFTPTransfer.USE_COMPRESSION,
+            SFTPTransfer.PROXY_CONFIGURATION_SERVICE,
+            FTPTransfer.PROXY_TYPE,
+            FTPTransfer.PROXY_HOST,
+            FTPTransfer.PROXY_PORT,
+            FTPTransfer.HTTP_PROXY_USERNAME,
+            FTPTransfer.HTTP_PROXY_PASSWORD,
+            SFTPTransfer.CIPHERS_ALLOWED,
+            SFTPTransfer.KEY_ALGORITHMS_ALLOWED,
+            SFTPTransfer.KEY_EXCHANGE_ALGORITHMS_ALLOWED,
+            SFTPTransfer.MESSAGE_AUTHENTICATION_CODES_ALLOWED
+    );
+
+    @Override
+    public Set<Relationship> getRelationships() {
+        return relationships;
+    }
+
+    @Override
+    protected List<PropertyDescriptor> getSupportedPropertyDescriptors() {
+        return properties;
+    }
+
+    @Override
+    public void onTrigger(ProcessContext context, ProcessSession session) throws ProcessException {
+        FlowFile flowFile = session.get();
+        if (flowFile == null) {
+            return;
+        }
+
+        final ComponentLog logger = getLogger();
+        String hostname = context.getProperty(FileTransfer.HOSTNAME).evaluateAttributeExpressions(flowFile).getValue();
+
+        final int maxNumberOfFiles = context.getProperty(SFTPTransfer.BATCH_SIZE).asInteger();
+        int fileCount = 0;
+
+        try (final SFTPTransfer transfer = new SFTPTransfer(context, logger)) {
+            do {
+                //evaluate again inside the loop as each flowfile can have a different hostname
+                hostname = context.getProperty(FileTransfer.HOSTNAME).evaluateAttributeExpressions(flowFile).getValue();
+
+                final long startNanos = System.nanoTime();
+
+                final String directoryPathProperty = context.getProperty(DIRECTORY_PATH).evaluateAttributeExpressions(flowFile).getValue();
+                final String filename = context.getProperty(FILENAME).evaluateAttributeExpressions(flowFile).getValue();
+
+                try {
+                    final Path directoryPath = Paths.get(directoryPathProperty).normalize();
+                    final Path filePath = directoryPath.resolve(filename).normalize();
+
+                    if (!directoryPath.equals(filePath.getParent())) {
+                        final String errorMessage = "Attempting to delete file at path '%s' which is not a direct child of the directory '%s'"
+                                .formatted(filePath, directoryPath);
+
+                        handleFailure(session, flowFile, errorMessage, null);
+                        continue;
+                    }
+
+                    transfer.deleteFile(flowFile, directoryPath.toString(), filename);
+
+                    session.transfer(flowFile, REL_SUCCESS);
+                    final String transitUri = "sftp://%s".formatted(filePath);
+                    final long transferMillis = TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - startNanos);
+                    logger.debug("Successfully deleted file at path {} in {} millis; routing to success", flowFile, transferMillis);
+                    session.getProvenanceReporter().invokeRemoteProcess(flowFile, transitUri, "Object deleted");
+                } catch (FileNotFoundException fileNotFoundException) {
+                    session.transfer(flowFile, REL_NOT_FOUND);
+                } catch (IOException ioException) {
+                    final String errorMessage = "Failed to delete file '%s' in directory '%s'"
+                            .formatted(filename, directoryPathProperty);
+
+                    handleFailure(session, flowFile, errorMessage, ioException);
+                }
+            } while (isScheduled()
+                    && (getRelationships().size() == context.getAvailableRelationships().size())
+                    && (++fileCount < maxNumberOfFiles)
+                    && ((flowFile = session.get()) != null));
+        } catch (final IOException | FlowFileAccessException | ProcessException e) {
+            context.yield();
+
+            Throwable cause = switch (e) {
+                case FlowFileAccessException ffaEx -> ffaEx.getCause();
+                case ProcessException pEx -> pEx.getCause();
+                default -> e;
+            };
+
+            String errorMessage = "Routing to failure since unable to delete %s from remote host %s".formatted(flowFile, hostname);
+            handleFailure(session, flowFile, errorMessage, cause);
+        }
+    }
+
+    @Override
+    protected Collection<ValidationResult> customValidate(ValidationContext validationContext) {
+        final Collection<ValidationResult> results = new ArrayList<>();
+        SFTPTransfer.validateProxySpec(validationContext, results);
+        return results;
+    }
+
+    private void handleFailure(ProcessSession session, FlowFile flowFile, String errorMessage, Throwable throwable) {
+        getLogger().error(errorMessage, throwable);
+
+        session.penalize(flowFile);
+        session.transfer(flowFile, REL_FAILURE);
+    }
+}

nifi-extension-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/resources/META-INF/services/org.apache.nifi.processor.Processor

@@ -23,6 +23,7 @@ org.apache.nifi.processors.standard.CountText
 org.apache.nifi.processors.standard.CryptographicHashContent
 org.apache.nifi.processors.standard.DebugFlow
 org.apache.nifi.processors.standard.DeleteFile
+org.apache.nifi.processors.standard.DeleteSFTP
 org.apache.nifi.processors.standard.DetectDuplicate
 org.apache.nifi.processors.standard.DeduplicateRecord
 org.apache.nifi.processors.standard.DistributeLoad