/**
* Copyright: 2013 Regents of the University of California and the
* National Center for Ecological Analysis and Synthesis
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package edu.ucsb.nceas.metacat.common.query;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.solr.common.params.AppendedSolrParams;
import org.apache.solr.common.params.SolrParams;
import org.apache.solr.common.util.NamedList;
import org.apache.solr.schema.IndexSchema;
import org.apache.solr.schema.SchemaField;
import org.dataone.service.types.v1.Subject;
import org.dataone.service.util.Constants;
import edu.ucsb.nceas.metacat.common.query.SolrQueryResponseWriterFactory;
/**
* An abstract query service class for the solr server
* @author tao
*
*/
public abstract class SolrQueryService {
public static final String WT = "wt";//the property name to specify the return type
protected static final String FILTERQUERY = "fq";
protected static final String UNKNOWN = "Unknown";
private static final String READPERMISSION = "readPermission";
private static final String IS_PUBLIC = "isPublic";
private static final String RIGHTSHOLDER = "rightsHolder";
private static final String OPENPARENTHESE = "(";
private static final String CLOSEPARENTHESE = ")";
private static final String COLON = ":";
private static final String OR = "OR";
private static Log log = LogFactory.getLog(SolrQueryService.class);
private static List<String> supportedWriterTypes = null;
protected IndexSchema schema = null;
protected Map<String, SchemaField> fieldMap = null;
protected List<String> validSolrFieldNames = null;
protected String solrSpecVersion = null;
static {
supportedWriterTypes = new ArrayList<String>();
supportedWriterTypes.add(SolrQueryResponseWriterFactory.CSV);
supportedWriterTypes.add(SolrQueryResponseWriterFactory.JSON);
supportedWriterTypes.add(SolrQueryResponseWriterFactory.PHP);
supportedWriterTypes.add(SolrQueryResponseWriterFactory.PHPS);
supportedWriterTypes.add(SolrQueryResponseWriterFactory.RUBY);
supportedWriterTypes.add(SolrQueryResponseWriterFactory.VELOCITY);
supportedWriterTypes.add(SolrQueryResponseWriterFactory.PYTHON);
supportedWriterTypes.add(SolrQueryResponseWriterFactory.XML);
}
/**
* Query the Solr server with specified query and user's identity. If the Subjects
* is null, there will be no access rules for the query. This is for the embedded solr server.
* @param query the query params.
* @param subjects the user's identity which sent the query
* @return the response
* @throws Exception
*/
public abstract InputStream query(SolrParams query, Set<Subject>subjects) throws Exception;
/**
* Get the fields list of the index schema
* @return
* @throws Exception
*/
public abstract Map<String, SchemaField> getIndexSchemaFields() throws Exception;
public IndexSchema getSchema() {
return schema;
}
/**
* Get the version of the solr server.
* @return
*/
public abstract String getSolrServerVersion();
/**
* Get the list of the valid field name (moved the fields names of the CopyFieldTarget).
* @return
*/
protected List<String> getValidSchemaFields() {
if (validSolrFieldNames != null && !validSolrFieldNames.isEmpty()) {
//System.out.println("the valid file name is\n"+validSolrFieldNames);
return validSolrFieldNames;
} else {
validSolrFieldNames = new ArrayList<String>();
if(fieldMap != null) {
Set<String> fieldNames = fieldMap.keySet();
for(String fieldName : fieldNames) {
SchemaField field = fieldMap.get(fieldName);
//remove the field which is the target field of a CopyField.
if(field != null && !schema.isCopyFieldTarget(field)) {
validSolrFieldNames.add(fieldName);
}
}
}
//System.out.println("the valid file name is\n"+validSolrFieldNames);
return validSolrFieldNames;
}
}
/**
* If the solr server supports the specified wt.
* @param wt
* @return true if it supports; otherwise false.
*/
public static boolean isSupportedWT(String wt) {
if (wt == null ||supportedWriterTypes.contains(wt)) {
return true;
} else {
return false;
}
}
/*
* Append the access filter query to the params
*/
protected SolrParams appendAccessFilterParams(SolrParams solrParams, Set<Subject>subjects) {
SolrParams append = null;
if(solrParams != null) {
StringBuffer query = generateAccessFilterParamsString(subjects);
if(query != null && query.length() != 0) {
log.info("=================== fq query is "+query.toString());
NamedList fq = new NamedList();
fq.add(FILTERQUERY, query.toString());
SolrParams fqParam = SolrParams.toSolrParams(fq);
append = new AppendedSolrParams(solrParams, fqParam);
} else {
append = solrParams;
}
}
return append;
}
protected StringBuffer generateAccessFilterParamsString(Set<Subject>subjects) {
StringBuffer query = new StringBuffer();
boolean first = true;
if(subjects != null) {
for(Subject subject : subjects) {
if(subject != null) {
String subjectName = subject.getValue();
if(subjectName != null && !subjectName.trim().equals("")) {
if(first) {
first = false;
query.append(OPENPARENTHESE+READPERMISSION+COLON+"\""+subjectName+"\""+CLOSEPARENTHESE);
if(!subjectName.equals(Constants.SUBJECT_PUBLIC) && !subjectName.equals(Constants.SUBJECT_AUTHENTICATED_USER)) {
query.append(OR+OPENPARENTHESE+RIGHTSHOLDER+COLON+"\""+subjectName+"\""+CLOSEPARENTHESE);
} else if (subjectName.equals(Constants.SUBJECT_PUBLIC)) {
query.append(OR+OPENPARENTHESE+IS_PUBLIC+COLON+"true"+CLOSEPARENTHESE);
}
} else {
query.append(OR + OPENPARENTHESE+READPERMISSION+COLON+"\""+subjectName+"\""+CLOSEPARENTHESE);
if(!subjectName.equals(Constants.SUBJECT_PUBLIC) && !subjectName.equals(Constants.SUBJECT_AUTHENTICATED_USER)) {
query.append(OR + OPENPARENTHESE+RIGHTSHOLDER+COLON+"\""+subjectName+"\""+CLOSEPARENTHESE);
} else if (subjectName.equals(Constants.SUBJECT_PUBLIC)) {
query.append(OR+OPENPARENTHESE+IS_PUBLIC+COLON+"true"+CLOSEPARENTHESE);
}
}
}
}
}
}
return query;
}
}