Github user jskora commented on a diff in the pull request:
https://github.com/apache/nifi/pull/252#discussion_r67393537
--- Diff:
nifi-nar-bundles/nifi-media-bundle/nifi-media-processors/src/main/java/org/apache/nifi/processors/media/ExtractMediaMetadata.java
---
@@ -0,0 +1,276 @@
+/*
+ * 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.media;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.regex.Pattern;
+
+import org.apache.nifi.annotation.behavior.InputRequirement;
+import org.apache.nifi.annotation.behavior.InputRequirement.Requirement;
+import org.apache.nifi.annotation.behavior.SupportsBatching;
+import org.apache.nifi.annotation.behavior.WritesAttribute;
+import org.apache.nifi.annotation.behavior.WritesAttributes;
+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.flowfile.FlowFile;
+import org.apache.nifi.flowfile.attributes.CoreAttributes;
+import org.apache.nifi.logging.ProcessorLog;
+import org.apache.nifi.processor.AbstractProcessor;
+import org.apache.nifi.processor.ProcessContext;
+import org.apache.nifi.processor.ProcessSession;
+import org.apache.nifi.processor.ProcessorInitializationContext;
+import org.apache.nifi.processor.Relationship;
+import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.processor.io.InputStreamCallback;
+import org.apache.nifi.processor.util.StandardValidators;
+import org.apache.nifi.util.ObjectHolder;
+
+import org.apache.tika.exception.TikaException;
+import org.apache.tika.io.TikaInputStream;
+import org.apache.tika.metadata.Metadata;
+import org.apache.tika.parser.AutoDetectParser;
+import org.apache.tika.sax.BodyContentHandler;
+import org.xml.sax.SAXException;
+
+@InputRequirement(Requirement.INPUT_REQUIRED)
+@Tags({"media", "file", "format", "metadata", "audio", "video", "image",
"document", "pdf"})
+@CapabilityDescription("Extract the content metadata from flowfiles
containing audio, video, image, and other file "
+ + "types. This processor relies on the Apache Tika project for
file format detection and parsing. It "
+ + "extracts a long list of metadata types for media files
including audio, video, and print media "
+ + "formats."
+ + "For the more details and the list of supported file types,
visit the library's website "
+ + "at http://tika.apache.org/.";)
+@WritesAttributes({@WritesAttribute(attribute = "tika.<attribute>",
description = "The extracted content metadata "
+ + "will be inserted with the attribute name \"tika.<attribute>\".
")})
+@SupportsBatching
+public class ExtractMediaMetadata extends AbstractProcessor {
+
+ public static final PropertyDescriptor MAX_NUMBER_OF_ATTRIBUTES = new
PropertyDescriptor.Builder()
+ .name("Max Number of Attributes")
+ .description("Specify the max number of attributes to add to
the flowfile. There is no guarantee in what order"
+ + " the tags will be processed. By default it will
process all of them.")
+ .required(false)
+
.addValidator(StandardValidators.NON_NEGATIVE_INTEGER_VALIDATOR)
+ .build();
+
+ public static final PropertyDescriptor FILENAME_FILTER = new
PropertyDescriptor.Builder()
+ .name("File Name Filter")
+ .description("A regular expression identifying file names
which metadata should extracted. As flowfiles"
+ + " are processed, if the file name matches this
regular expression or this expression is"
+ + " blank, the flowfile will be scanned for it's MIME
type and metadata. If left blank, all"
+ + " flowfiles will be scanned.")
+ .required(false)
+ .addValidator(StandardValidators.REGULAR_EXPRESSION_VALIDATOR)
+ .build();
+
+ public static final PropertyDescriptor MIME_TYPE_FILTER = new
PropertyDescriptor.Builder()
+ .name("MIME Type Filter")
+ .description("A regular expression identifying MIME types for
which metadata should extracted. Flowfiles"
+ + " selected for scanning by the File Name Filter are
parsed to determine the MIME type and extract"
+ + " metadata. If the MIME type found matches this
regular expression or this expression is"
+ + " blank, the metadata keys that match the Metadata
Key Filter will be added to the flowfile"
+ + " attributes. There is no guarantee in what order
attributes will be produced. If"
+ + " left blank, metadata will be extracted from all
flow files selected for scanning.")
+ .required(false)
+ .addValidator(StandardValidators.REGULAR_EXPRESSION_VALIDATOR)
+ .build();
+
+ public static final PropertyDescriptor METADATA_KEY_FILTER = new
PropertyDescriptor.Builder()
+ .name("Metadata Key Filter")
+ .description("A regular expression identifying which metadata
keys received from the parser should be"
+ + " added to the flowfile attributes. If left blank,
all metadata keys parsed will be added to the"
+ + " flowfile attributes.")
+ .required(false)
+ .addValidator(StandardValidators.REGULAR_EXPRESSION_VALIDATOR)
+ .build();
+
+ public static final PropertyDescriptor METADATA_KEY_PREFIX = new
PropertyDescriptor.Builder()
+ .name("Metadata Key Prefix")
+ .description("Text to be prefixed to metadata keys as the are
added to the flowfile attributes. It is"
+ + " recommended to end with with a separator character
like '.' or '-', this is not automatically "
+ + " added by the processor.")
+ .required(false)
+ .addValidator(StandardValidators.ATTRIBUTE_KEY_VALIDATOR)
+ .expressionLanguageSupported(true)
+ .build();
+
+ public static final Relationship SUCCESS = new Relationship.Builder()
+ .name("success")
+ .description("Any FlowFile that successfully has image
metadata extracted will be routed to success")
+ .build();
+
+ public static final Relationship FAILURE = new Relationship.Builder()
+ .name("failure")
+ .description("Any FlowFile that fails to have image metadata
extracted will be routed to failure")
+ .build();
+
+ private Set<Relationship> relationships;
+ private List<PropertyDescriptor> properties;
+
+ private final AtomicReference<Pattern> filenameFilterRef = new
AtomicReference<>();
+ private final AtomicReference<Pattern> mimeTypeFilterRef = new
AtomicReference<>();
+ private final AtomicReference<Pattern> metadataKeyFilterRef = new
AtomicReference<>();
+
+ @Override
+ protected void init(final ProcessorInitializationContext context) {
+
+ final List<PropertyDescriptor> properties = new ArrayList<>();
+ properties.add(MAX_NUMBER_OF_ATTRIBUTES);
+ properties.add(FILENAME_FILTER);
+ properties.add(MIME_TYPE_FILTER);
+ properties.add(METADATA_KEY_FILTER);
+ properties.add(METADATA_KEY_PREFIX);
+ this.properties = Collections.unmodifiableList(properties);
+
+ final Set<Relationship> relationships = new HashSet<>();
+ relationships.add(SUCCESS);
+ relationships.add(FAILURE);
+ this.relationships = Collections.unmodifiableSet(relationships);
+ }
+
+ @Override
+ public Set<Relationship> getRelationships() {
+ return this.relationships;
+ }
+
+ @Override
+ protected List<PropertyDescriptor> getSupportedPropertyDescriptors() {
+ return this.properties;
+ }
+
+ @OnScheduled
+ public void onScheduled(ProcessContext context) {
+ final String fileNamePatternInput =
context.getProperty(FILENAME_FILTER).getValue();
+ if (fileNamePatternInput != null && fileNamePatternInput.length()
> 0) {
+ filenameFilterRef.set(Pattern.compile(fileNamePatternInput));
+ } else {
+ filenameFilterRef.set(null);
+ }
+
+ final String mimeTypeFilterInput =
context.getProperty(MIME_TYPE_FILTER).getValue();
+ if (mimeTypeFilterInput != null && mimeTypeFilterInput.length() >
0) {
+ mimeTypeFilterRef.set(Pattern.compile(mimeTypeFilterInput));
+ } else {
+ mimeTypeFilterRef.set(null);
+ }
+
+ String metadataKeyFilterInput =
context.getProperty(METADATA_KEY_FILTER).getValue();
+ if (metadataKeyFilterInput != null &&
metadataKeyFilterInput.length() > 0) {
+
metadataKeyFilterRef.set(Pattern.compile(metadataKeyFilterInput));
+ } else {
+ metadataKeyFilterRef.set(null);
+ }
+ }
+
+ @Override
+ public void onTrigger(final ProcessContext context, final
ProcessSession session) throws ProcessException {
+ FlowFile flowfile = session.get();
+ if (flowfile == null) {
+ return;
+ }
+
+ // fail fast if filename doesn't match filter
+ Pattern filenameFilter = filenameFilterRef.get();
+ if (filenameFilter != null &&
!filenameFilter.matcher(flowfile.getAttribute(CoreAttributes.FILENAME.key())).matches())
{
+ session.transfer(flowfile, SUCCESS);
+ return;
+ }
+
+ final ProcessorLog logger = this.getLogger();
+ final ObjectHolder<Map<String, String>> value = new
ObjectHolder<>(null);
+ final Integer max =
context.getProperty(MAX_NUMBER_OF_ATTRIBUTES).asInteger();
+ final String prefix =
context.getProperty(METADATA_KEY_PREFIX).evaluateAttributeExpressions().getValue();
+ final FlowFile ff = flowfile;
+
+ try {
+ session.read(flowfile, new InputStreamCallback() {
+ @Override
+ public void process(InputStream in) throws IOException {
+ try {
+ Map<String, String> results = tika_parse(ff, in,
prefix, max);
+ value.set(results);
+ } catch (SAXException | TikaException e) {
+ throw new IOException(e);
+ }
+ }
+ });
+
+ // Write the results to attributes
+ Map<String, String> results = value.get();
+ if (results != null && !results.isEmpty()) {
+ flowfile = session.putAllAttributes(flowfile, results);
+ }
+
+ session.transfer(flowfile, SUCCESS);
+ } catch (ProcessException e) {
+ logger.error("Failed to extract media metadata from {} due to
{}", new Object[]{flowfile, e});
+ session.transfer(flowfile, FAILURE);
+ }
+ }
+
+ private Map<String, String> tika_parse(FlowFile ff, InputStream
sourceStream, String prefix, Integer max) throws IOException, TikaException,
SAXException {
+ final Metadata metadata = new Metadata();
+ final TikaInputStream tikaInputStream =
TikaInputStream.get(sourceStream);
+ new AutoDetectParser().parse(tikaInputStream, new
BodyContentHandler(), metadata);
+ final String content_type = metadata.get(Metadata.CONTENT_TYPE);
+
+ // if parsed MIME type doesn't match filter fail fast without
processing attributes
+ final Pattern mimeTypeFilter = mimeTypeFilterRef.get();
+ if (mimeTypeFilter != null && (content_type == null ||
!mimeTypeFilter.matcher(metadata.get(Metadata.CONTENT_TYPE)).matches())) {
+ return null;
+ }
+
+ final Map<String, String> results = new HashMap<>();
+ final Pattern metadataKeyFilter = metadataKeyFilterRef.get();
+ final StringBuilder dataBuilder = new StringBuilder();
+ final String safePrefix = (prefix == null) ? "" : prefix;
+ for (final String key : metadata.names()) {
+ if (metadataKeyFilter != null &&
!metadataKeyFilter.matcher(key).matches()) {
+ continue;
+ }
+ dataBuilder.setLength(0);
+ if (metadata.isMultiValued(key)) {
+ for (String val : metadata.getValues(key)) {
+ if (dataBuilder.length() > 1) {
+ dataBuilder.append(", ");
+ }
+ dataBuilder.append(val);
--- End diff --
Property added for maximum length of an attribute value.
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