Github user bdesert commented on a diff in the pull request:
https://github.com/apache/nifi/pull/2711#discussion_r190298869
--- Diff:
nifi-nar-bundles/nifi-standard-bundle/nifi-standard-processors/src/main/java/org/apache/nifi/processors/standard/AttributesToCSV.java
---
@@ -0,0 +1,272 @@
+/*
+ * 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.commons.lang3.StringEscapeUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.apache.nifi.annotation.behavior.EventDriven;
+import org.apache.nifi.annotation.behavior.SideEffectFree;
+import org.apache.nifi.annotation.behavior.SupportsBatching;
+import org.apache.nifi.annotation.behavior.InputRequirement;
+import org.apache.nifi.annotation.behavior.WritesAttribute;
+import org.apache.nifi.annotation.documentation.CapabilityDescription;
+import org.apache.nifi.annotation.documentation.Tags;
+import org.apache.nifi.annotation.lifecycle.OnScheduled;
+import org.apache.nifi.components.PropertyDescriptor;
+import org.apache.nifi.expression.ExpressionLanguageScope;
+import org.apache.nifi.flowfile.FlowFile;
+import org.apache.nifi.flowfile.attributes.CoreAttributes;
+import org.apache.nifi.processor.AbstractProcessor;
+import org.apache.nifi.processor.ProcessContext;
+import org.apache.nifi.processor.ProcessorInitializationContext;
+import org.apache.nifi.processor.ProcessSession;
+import org.apache.nifi.processor.Relationship;
+import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.processor.util.StandardValidators;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.ArrayList;
+import java.util.Set;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Collections;
+import java.util.stream.Collectors;
+
+@EventDriven
+@SideEffectFree
+@SupportsBatching
+@Tags({"csv", "attributes", "flowfile"})
+@InputRequirement(InputRequirement.Requirement.INPUT_REQUIRED)
+@CapabilityDescription("Generates a CSV representation of the input
FlowFile Attributes. The resulting CSV " +
+ "can be written to either a newly generated attribute named
'CSVAttributes' or written to the FlowFile as content. " +
+ "If the attribute value contains a comma, newline or double quote,
then the attribute value will be " +
+ "escaped with double quotes. Any double quote characters in the
attribute value are escaped with " +
+ "another double quote. If the attribute value does not contain a
comma, newline or double quote, then the " +
+ "attribute value is returned unchanged.")
+@WritesAttribute(attribute = "CSVAttributes", description = "CSV
representation of Attributes")
+public class AttributesToCSV extends AbstractProcessor {
+
+ private static final String OUTPUT_NEW_ATTRIBUTE =
"flowfile-attribute";
+ private static final String OUTPUT_OVERWRITE_CONTENT =
"flowfile-content";
+ private static final String OUTPUT_ATTRIBUTE_NAME = "CSVAttributes";
+ private static final String OUTPUT_SEPARATOR = ",";
+ private static final String OUTPUT_MIME_TYPE = "text/csv";
+
+
+ public static final PropertyDescriptor ATTRIBUTES_LIST = new
PropertyDescriptor.Builder()
+ .name("attribute-list")
+ .displayName("Attribute List")
+ .description("Comma separated list of attributes to be
included in the resulting CSV. If this value " +
+ "is left empty then all existing Attributes will be
included. This list of attributes is " +
+ "case sensitive and does not support attribute names
that contain commas. If an attribute specified in the list is not found it will
be emitted " +
+ "to the resulting CSV with an empty string or null
depending on the 'Null Value' property. " +
+ "If a core attribute is specified in this list " +
+ "and the 'Include Core Attributes' property is false,
the core attribute will be included. The attribute list " +
+ "ALWAYS wins.")
+ .required(false)
+ .addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
+
.expressionLanguageSupported(ExpressionLanguageScope.FLOWFILE_ATTRIBUTES)
+ .build();
+
+ public static final PropertyDescriptor DESTINATION = new
PropertyDescriptor.Builder()
+ .name("destination")
+ .displayName("Destination")
+ .description("Control if CSV value is written as a new
flowfile attribute 'CSVAttributes' " +
+ "or written in the flowfile content. Writing to
flowfile content will overwrite any " +
+ "existing flowfile content.")
+ .required(true)
+ .allowableValues(OUTPUT_NEW_ATTRIBUTE,
OUTPUT_OVERWRITE_CONTENT)
+ .defaultValue(OUTPUT_NEW_ATTRIBUTE)
+ .build();
+
+ public static final PropertyDescriptor INCLUDE_CORE_ATTRIBUTES = new
PropertyDescriptor.Builder()
+ .name("include-core-userSpecifiedAttributes")
+ .displayName("Include Core Attributes")
+ .description("Determines if the FlowFile
org.apache.nifi.flowfile.attributes.CoreAttributes, which are " +
+ "contained in every FlowFile, should be included in
the final CSV value generated. The Attribute List property " +
+ "overrides this setting.")
+ .required(true)
+ .allowableValues("true", "false")
+ .defaultValue("true")
+ .build();
+
+ public static final PropertyDescriptor NULL_VALUE_FOR_EMPTY_STRING =
new PropertyDescriptor.Builder()
+ .name(("null-value"))
+ .displayName("Null Value")
+ .description("If true a non existing or empty attribute will
be 'null' in the resulting CSV. If false an empty " +
+ "string will be placed in the CSV")
+ .required(true)
+ .allowableValues("true", "false")
+ .defaultValue("false")
+ .build();
+
+
+ public static final Relationship REL_SUCCESS = new
Relationship.Builder().name("success")
+ .description("Successfully converted attributes to
CSV").build();
+ public static final Relationship REL_FAILURE = new
Relationship.Builder().name("failure")
+ .description("Failed to convert attributes to CSV").build();
+
+ private List<PropertyDescriptor> properties;
+ private Set<Relationship> relationships;
+ private volatile Set<String> userSpecifiedAttributes;
--- End diff --
This variable isn't being reused as object level variable. Also, you reset
it every time in onTrigger, and pass as param to other methods. IMO it's better
to keep it as local variable in onTrigger method.
---
