/* The contents of this file are subject to the license and copyright terms
* detailed in the license directory at the root of the source tree (also
* available online at http://fedora-commons.org/license/).
*/
package org.fcrepo.server.search;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import org.fcrepo.server.errors.ModuleInitializationException;
import org.fcrepo.server.errors.ObjectIntegrityException;
import org.fcrepo.server.errors.RepositoryConfigurationException;
import org.fcrepo.server.errors.ServerException;
import org.fcrepo.server.errors.StorageDeviceException;
import org.fcrepo.server.errors.StreamIOException;
import org.fcrepo.server.errors.UnknownSessionTokenException;
import org.fcrepo.server.errors.UnrecognizedFieldException;
import org.fcrepo.server.storage.ConnectionPool;
import org.fcrepo.server.storage.DOReader;
import org.fcrepo.server.storage.RepositoryReader;
import org.fcrepo.server.storage.types.Datastream;
import org.fcrepo.server.utilities.DCField;
import org.fcrepo.server.utilities.DCFields;
import org.fcrepo.server.utilities.SQLUtility;
import org.fcrepo.utilities.DateUtility;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A FieldSearch implementation that uses a relational database as a backend.
*
* @author Chris Wilper
*/
public class FieldSearchSQLImpl
implements FieldSearch {
private static final Logger logger =
LoggerFactory.getLogger(FieldSearchSQLImpl.class);
/** Whether DC fields are being indexed or not. */
private boolean m_indexDCFields = true;
private final ConnectionPool m_cPool;
private final RepositoryReader m_repoReader;
private final int m_maxResults;
private final int m_maxSecondsPerSession;
public static String[] DB_COLUMN_NAMES =
new String[] {"pid", "label", "state", "ownerId", "cDate", "mDate",
"dcmDate", "dcTitle", "dcCreator", "dcSubject",
"dcDescription", "dcPublisher", "dcContributor", "dcDate",
"dcType", "dcFormat", "dcIdentifier", "dcSource",
"dcLanguage", "dcRelation", "dcCoverage", "dcRights"};
private static boolean[] s_dbColumnNumeric =
new boolean[] {false, false, false, false, true, true, true, false,
false, false, false, false, false, false, false, false,
false, false, false, false, false, false};
public static String[] DB_COLUMN_NAMES_NODC =
new String[] {"pid", "label", "state", "ownerId", "cDate", "mDate",
"dcmDate"};
private static boolean[] s_dbColumnNumericNoDC =
new boolean[] {false, false, false, false, true, true, true};
// a hash of token-keyed FieldSearchResultSQLImpls
private final Map<String, FieldSearchResultSQLImpl> m_currentResults =
new ConcurrentHashMap<String, FieldSearchResultSQLImpl>();
/**
* Construct a FieldSearchSQLImpl that indexes DC fields.
*
* @param cPool
* the ConnectionPool with connections to the db containing the
* fields
* @param repoReader
* the RepositoryReader to use when getting the original values of
* the fields
* @param maxResults
* the maximum number of results to return at a time, regardless of
* what the user might request
* @param maxSecondsPerSession
* maximum number of seconds per session.
* @throws ModuleInitializationException
*/
public FieldSearchSQLImpl(ConnectionPool cPool,
RepositoryReader repoReader,
int maxResults,
int maxSecondsPerSession,
SQLUtility sqlUtility) throws ModuleInitializationException {
this(cPool, repoReader, maxResults, maxSecondsPerSession, true);
}
/**
* Construct a FieldSearchSQLImpl that indexes DC fields only if specified.
*
* @param cPool
* the ConnectionPool with connections to the db containing the
* fields
* @param repoReader
* the RepositoryReader to use when getting the original values of
* the fields
* @param maxResults
* the maximum number of results to return at a time, regardless of
* what the user might request
* @param maxSecondsPerSession
* maximum number of seconds per session.
* @param indexDCFields
* whether DC field values should be examined and updated in the
* database. If false, queries will behave as if no values had been
* specified for the DC fields.
* @throws ModuleInitializationException
*/
public FieldSearchSQLImpl(ConnectionPool cPool,
RepositoryReader repoReader,
int maxResults,
int maxSecondsPerSession,
boolean indexDCFields) throws ModuleInitializationException {
logger.debug("Entering constructor");
m_cPool = cPool;
m_repoReader = repoReader;
m_maxResults = maxResults;
m_maxSecondsPerSession = maxSecondsPerSession;
m_indexDCFields = indexDCFields;
try {
String dbSpec =
"org/fcrepo/server/storage/resources/FieldSearchSQLImpl.dbspec";
InputStream specIn =
this.getClass().getClassLoader()
.getResourceAsStream(dbSpec);
if (specIn == null) {
throw new IOException("Cannot find required resource: " +
dbSpec);
}
SQLUtility.createNonExistingTables(m_cPool, specIn);
} catch (Exception e) {
throw new ModuleInitializationException(
"Error while attempting to check for and create non-existing table(s): " +
e.getClass().getName() + ": " + e.getMessage(), getRole(), e);
}
logger.debug("Exiting constructor");
}
public String getRole() {
return FieldSearch.class.getName();
}
public void update(DOReader reader) throws ServerException {
logger.debug("Entering update(DOReader)");
String pid = reader.GetObjectPID();
Connection conn = null;
PreparedStatement st = null;
try {
conn = m_cPool.getReadWriteConnection();
String[] dbRowValues;
if (m_indexDCFields) {
dbRowValues = new String[DB_COLUMN_NAMES.length];
} else {
dbRowValues = new String[DB_COLUMN_NAMES_NODC.length];
}
dbRowValues[0] = reader.GetObjectPID();
String v;
v = reader.GetObjectLabel();
if (v != null) {
v = v.toLowerCase();
}
dbRowValues[1] = v;
dbRowValues[2] = reader.GetObjectState().toLowerCase();
v = reader.getOwnerId();
if (v != null) {
v = v.toLowerCase();
}
dbRowValues[3] = v;
Date date = reader.getCreateDate();
if (date == null) { // should never happen, but if it does, don't die
date = new Date();
}
dbRowValues[4] = "" + date.getTime();
date = reader.getLastModDate();
if (date == null) { // should never happen, but if it does, don't die
date = new Date();
}
dbRowValues[5] = "" + date.getTime();
// do dc stuff if needed
Datastream dcmd = null;
try {
dcmd = reader.GetDatastream("DC", null);
} catch (ClassCastException cce) {
throw new ObjectIntegrityException("Object "
+ reader.GetObjectPID()
+ " has a DC datastream, but it's not inline XML.");
}
if (dcmd == null) {
dbRowValues[6] = "0";
} else {
dbRowValues[6] = "" + dcmd.DSCreateDT.getTime();
}
if (dcmd != null && m_indexDCFields) {
InputStream in = dcmd.getContentStream();
DCFields dc = new DCFields(in);
dbRowValues[7] = getDbValue(dc.titles());
dbRowValues[8] = getDbValue(dc.creators());
dbRowValues[9] = getDbValue(dc.subjects());
dbRowValues[10] = getDbValue(dc.descriptions());
dbRowValues[11] = getDbValue(dc.publishers());
dbRowValues[12] = getDbValue(dc.contributors());
dbRowValues[13] = getDbValue(dc.dates());
// delete any dc.dates that survive from earlier versions
st = conn.prepareStatement("DELETE FROM dcDates WHERE pid=?");
st.setString(1, pid);
st.executeUpdate();
// get any dc.dates strings that are formed such that they
// can be treated as a timestamp
List<Date> wellFormedDates = null;
for (int i = 0; i < dc.dates().size(); i++) {
if (i == 0) {
wellFormedDates = new ArrayList<Date>();
}
Date p = DateUtility.parseDateLoose(dc.dates().get(i).getValue());
if (p != null) {
wellFormedDates.add(p);
}
}
if (wellFormedDates != null && wellFormedDates.size() > 0) {
// found at least one valid date, so add them.
for (int i = 0; i < wellFormedDates.size(); i++) {
Date dt = wellFormedDates.get(i);
String query =
"INSERT INTO dcDates (pid, dcDate) values (?, ?)";
st = conn.prepareStatement(query);
st.setString(1, pid);
st.setLong(2, dt.getTime());
st.executeUpdate();
}
}
dbRowValues[14] = getDbValue(dc.types());
dbRowValues[15] = getDbValue(dc.formats());
dbRowValues[16] = getDbValue(dc.identifiers());
dbRowValues[17] = getDbValue(dc.sources());
dbRowValues[18] = getDbValue(dc.languages());
dbRowValues[19] = getDbValue(dc.relations());
dbRowValues[20] = getDbValue(dc.coverages());
dbRowValues[21] = getDbValue(dc.rights());
logger.debug("Formulating SQL and inserting/updating WITH DC...");
SQLUtility.replaceInto(conn,
"doFields",
DB_COLUMN_NAMES,
dbRowValues,
"pid",
s_dbColumnNumeric);
} else {
logger.debug("Formulating SQL and inserting/updating WITHOUT DC...");
SQLUtility.replaceInto(conn,
"doFields",
DB_COLUMN_NAMES_NODC,
dbRowValues,
"pid",
s_dbColumnNumericNoDC);
}
} catch (SQLException sqle) {
throw new StorageDeviceException("Error attempting FieldSearch "
+ "update of " + pid, sqle);
} finally {
try {
if (st != null) {
st.close();
}
if (conn != null) {
m_cPool.free(conn);
}
} catch (SQLException sqle2) {
throw new StorageDeviceException("Error closing statement "
+ "while attempting update of object"
+ sqle2.getMessage());
} finally {
st = null;
logger.debug("Exiting update(DOReader)");
}
}
}
public boolean delete(String pid) throws ServerException {
logger.debug("Entering delete(String)");
Connection conn = null;
PreparedStatement st = null;
try {
conn = m_cPool.getReadWriteConnection();
st = conn.prepareStatement("DELETE FROM doFields WHERE pid=?");
st.setString(1, pid);
st.executeUpdate();
st.close();
st = conn.prepareStatement("DELETE FROM dcDates WHERE pid=?");
st.setString(1, pid);
st.executeUpdate();
return true;
} catch (SQLException sqle) {
throw new StorageDeviceException("Error attempting delete of "
+ "object with pid '" + pid + "': " + sqle.getMessage());
} finally {
try {
if (st != null) {
st.close();
}
if (conn != null) {
m_cPool.free(conn);
}
} catch (SQLException sqle2) {
throw new StorageDeviceException("Error closing statement "
+ "while attempting update of object"
+ sqle2.getMessage());
} finally {
st = null;
logger.debug("Exiting delete(String)");
}
}
}
public FieldSearchResult findObjects(String[] resultFields,
int maxResults,
FieldSearchQuery query)
throws UnrecognizedFieldException, ObjectIntegrityException,
RepositoryConfigurationException, StreamIOException,
ServerException, StorageDeviceException {
closeAndForgetOldResults();
int actualMax = maxResults;
if (m_maxResults < maxResults) {
actualMax = m_maxResults;
}
try {
return stepAndRemember(new FieldSearchResultSQLImpl(m_cPool,
m_repoReader,
resultFields,
actualMax,
m_maxSecondsPerSession,
query));
} catch (SQLException sqle) {
throw new StorageDeviceException("Error querying sql db: "
+ sqle.getMessage(), sqle);
}
}
public FieldSearchResult resumeFindObjects(String sessionToken)
throws UnrecognizedFieldException, ObjectIntegrityException,
RepositoryConfigurationException, StreamIOException,
ServerException, UnknownSessionTokenException {
closeAndForgetOldResults();
FieldSearchResultSQLImpl result =
m_currentResults
.remove(sessionToken);
if (result == null) {
throw new UnknownSessionTokenException("Session is expired "
+ "or never existed.");
}
return stepAndRemember(result);
}
private FieldSearchResult stepAndRemember(FieldSearchResultSQLImpl result)
throws UnrecognizedFieldException, ObjectIntegrityException,
RepositoryConfigurationException, StreamIOException,
ServerException, UnrecognizedFieldException {
result.step();
if (result.getToken() != null) {
m_currentResults.put(result.getToken(), result);
}
return result;
}
// erase and cleanup expired stuff
private void closeAndForgetOldResults() {
Iterator<FieldSearchResultSQLImpl> iter =
m_currentResults.values().iterator();
while (iter.hasNext()) {
FieldSearchResultSQLImpl r = iter.next();
if (r.isExpired()) {
logger.debug("listSession " + r.getToken()
+ " expired; will forget it.");
iter.remove();
}
}
}
/**
* Get the string that should be inserted for a repeating-value column,
* given a list of values. Turn each value to lowercase and separate them
* all by space characters. If the list is empty, return null.
*
* @param dcFields
* a list of dublin core values
* @return String the string to insert
*/
private static String getDbValue(List<DCField> dcFields) {
if (dcFields.size() == 0) {
return null;
}
StringBuilder out = new StringBuilder(64 * dcFields.size());
for (DCField dcField : dcFields) {
out.append(' ');
out.append(dcField.getValue().toLowerCase());
}
out.append(" .");
return out.toString();
}
}