/*
* Licensed to Elastic Search and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Elastic Search 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.elasticsearch.search.highlight;
import org.elasticsearch.common.collect.Lists;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.search.SearchParseElement;
import org.elasticsearch.search.SearchParseException;
import org.elasticsearch.search.internal.SearchContext;
import java.util.List;
import static org.elasticsearch.common.collect.Lists.*;
/**
* <pre>
* highlight : {
* tags_schema : "styled",
* pre_tags : ["tag1", "tag2"],
* post_tags : ["tag1", "tag2"],
* order : "score",
* highlight_filter : true,
* fields : {
* field1 : { },
* field2 : { fragment_size : 100, number_of_fragments : 2 },
* field3 : { number_of_fragments : 5, order : "simple", tags_schema : "styled" },
* field4 : { number_of_fragments: 0, pre_tags : ["openingTagA", "openingTagB"], post_tags : ["closingTag"] }
* }
* }
* </pre>
*
* @author kimchy (shay.banon)
*/
public class HighlighterParseElement implements SearchParseElement {
private static final String[] DEFAULT_PRE_TAGS = new String[]{"<em>"};
private static final String[] DEFAULT_POST_TAGS = new String[]{"</em>"};
private static final String[] STYLED_PRE_TAG = {
"<em class=\"hlt1\">", "<em class=\"hlt2\">", "<em class=\"hlt3\">",
"<em class=\"hlt4\">", "<em class=\"hlt5\">", "<em class=\"hlt6\">",
"<em class=\"hlt7\">", "<em class=\"hlt8\">", "<em class=\"hlt9\">",
"<em class=\"hlt10\">"
};
private static final String[] STYLED_POST_TAGS = {"</em>"};
@Override public void parse(XContentParser parser, SearchContext context) throws Exception {
XContentParser.Token token;
String topLevelFieldName = null;
List<SearchContextHighlight.Field> fields = newArrayList();
String[] globalPreTags = DEFAULT_PRE_TAGS;
String[] globalPostTags = DEFAULT_POST_TAGS;
boolean globalScoreOrdered = false;
boolean globalHighlightFilter = true;
int globalFragmentSize = 100;
int globalNumOfFragments = 5;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
topLevelFieldName = parser.currentName();
} else if (token == XContentParser.Token.START_ARRAY) {
if ("pre_tags".equals(topLevelFieldName) || "preTags".equals(topLevelFieldName)) {
List<String> preTagsList = Lists.newArrayList();
while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
preTagsList.add(parser.text());
}
globalPreTags = preTagsList.toArray(new String[preTagsList.size()]);
} else if ("post_tags".equals(topLevelFieldName) || "postTags".equals(topLevelFieldName)) {
List<String> postTagsList = Lists.newArrayList();
while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
postTagsList.add(parser.text());
}
globalPostTags = postTagsList.toArray(new String[postTagsList.size()]);
}
} else if (token.isValue()) {
if ("order".equals(topLevelFieldName)) {
globalScoreOrdered = "score".equals(parser.text());
} else if ("tags_schema".equals(topLevelFieldName) || "tagsSchema".equals(topLevelFieldName)) {
String schema = parser.text();
if ("styled".equals(schema)) {
globalPreTags = STYLED_PRE_TAG;
globalPostTags = STYLED_POST_TAGS;
}
} else if ("highlight_filter".equals(topLevelFieldName) || "highlightFilter".equals(topLevelFieldName)) {
globalHighlightFilter = parser.booleanValue();
} else if ("fragment_size".equals(topLevelFieldName) || "fragmentSize".equals(topLevelFieldName)) {
globalFragmentSize = parser.intValue();
} else if ("number_of_fragments".equals(topLevelFieldName) || "numberOfFragments".equals(topLevelFieldName)) {
globalNumOfFragments = parser.intValue();
}
} else if (token == XContentParser.Token.START_OBJECT) {
if ("fields".equals(topLevelFieldName)) {
String highlightFieldName = null;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
highlightFieldName = parser.currentName();
} else if (token == XContentParser.Token.START_OBJECT) {
SearchContextHighlight.Field field = new SearchContextHighlight.Field(highlightFieldName);
String fieldName = null;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
fieldName = parser.currentName();
} else if (token == XContentParser.Token.START_ARRAY) {
if ("pre_tags".equals(fieldName) || "preTags".equals(fieldName)) {
List<String> preTagsList = Lists.newArrayList();
while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
preTagsList.add(parser.text());
}
field.preTags(preTagsList.toArray(new String[preTagsList.size()]));
} else if ("post_tags".equals(fieldName) || "postTags".equals(fieldName)) {
List<String> postTagsList = Lists.newArrayList();
while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
postTagsList.add(parser.text());
}
field.postTags(postTagsList.toArray(new String[postTagsList.size()]));
}
} else if (token.isValue()) {
if ("fragment_size".equals(fieldName) || "fragmentSize".equals(fieldName)) {
field.fragmentCharSize(parser.intValue());
} else if ("number_of_fragments".equals(fieldName) || "numberOfFragments".equals(fieldName)) {
field.numberOfFragments(parser.intValue());
} else if ("fragment_offset".equals(fieldName) || "fragmentOffset".equals(fieldName)) {
field.fragmentOffset(parser.intValue());
} else if ("highlight_filter".equals(fieldName) || "highlightFilter".equals(fieldName)) {
field.highlightFilter(parser.booleanValue());
} else if ("score".equals(fieldName)) {
field.scoreOrdered("score".equals(parser.text()));
}
}
}
fields.add(field);
}
}
}
}
}
if (globalPreTags != null && globalPostTags == null) {
throw new SearchParseException(context, "Highlighter global preTags are set, but global postTags are not set");
}
// now, go over and fill all fields with default values from the global state
for (SearchContextHighlight.Field field : fields) {
if (field.preTags() == null) {
field.preTags(globalPreTags);
}
if (field.postTags() == null) {
field.postTags(globalPostTags);
}
if (field.highlightFilter() == null) {
field.highlightFilter(globalHighlightFilter);
}
if (field.scoreOrdered() == null) {
field.scoreOrdered(globalScoreOrdered);
}
if (field.fragmentCharSize() == -1) {
field.fragmentCharSize(globalFragmentSize);
}
if (field.numberOfFragments() == -1) {
field.numberOfFragments(globalNumOfFragments);
}
}
context.highlight(new SearchContextHighlight(fields));
}
}