/* (c) 2014 Open Source Geospatial Foundation - all rights reserved
* (c) 2001 - 2013 OpenPlans
* This code is licensed under the GPL 2.0 license, available at the root
* application directory.
*/
package org.geoserver.wfs.response;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.text.NumberFormat;
import java.util.Collection;
import java.util.Date;
import java.util.Iterator;
import java.util.Locale;
import java.util.regex.Pattern;
import org.eclipse.xsd.XSDElementDeclaration;
import org.eclipse.xsd.impl.XSDElementDeclarationImpl;
import org.geoserver.config.GeoServer;
import org.geoserver.platform.Operation;
import org.geoserver.platform.ServiceException;
import org.geoserver.wfs.WFSGetFeatureOutputFormat;
import org.geoserver.wfs.request.FeatureCollectionResponse;
import org.geoserver.wfs.request.GetFeatureRequest;
import org.geotools.feature.FeatureCollection;
import org.geotools.feature.FeatureIterator;
import org.geotools.feature.type.DateUtil;
import org.opengis.feature.Feature;
import org.opengis.feature.Property;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.feature.type.AttributeDescriptor;
import org.opengis.feature.type.PropertyDescriptor;
/**
* WFS output format for a GetFeature operation in which the outputFormat is "csv".
* The refence specification for this format can be found in this RFC:
* http://www.rfc-editor.org/rfc/rfc4180.txt
*
* @author Justin Deoliveira, OpenGeo, jdeolive@opengeo.org
* @author Sebastian Benthall, OpenGeo, seb@opengeo.org
* @author Andrea Aime, OpenGeo
*/
public class CSVOutputFormat extends WFSGetFeatureOutputFormat {
static final Pattern CSV_ESCAPES = Pattern.compile("[\"\n,\r]");
public CSVOutputFormat(GeoServer gs) {
//this is the name of your output format, it is the string
// that will be used when requesting the format in a
// GEtFeature request:
// ie ;.../geoserver/wfs?request=getfeature&outputFormat=myOutputFormat
super(gs, "csv");
}
/**
* @return "text/csv";
*/
@Override
public String getMimeType(Object value, Operation operation)
throws ServiceException {
// won't allow browsers to open it directly, but that's the mime
// state in the RFC
return "text/csv";
}
@Override
public String getPreferredDisposition(Object value, Operation operation) {
return DISPOSITION_ATTACH;
}
@Override
public String getAttachmentFileName(Object value, Operation operation) {
GetFeatureRequest request = GetFeatureRequest.adapt(operation.getParameters()[0]);
String outputFileName = request.getQueries().get(0).getTypeNames().get(0).getLocalPart();
return outputFileName + ".csv";
}
/**
* @see WFSGetFeatureOutputFormat#write(Object, OutputStream, Operation)
*/
@Override
protected void write(FeatureCollectionResponse featureCollection,
OutputStream output, Operation getFeature) throws IOException,
ServiceException {
//write out content here
//create a writer
BufferedWriter w = new BufferedWriter( new OutputStreamWriter( output, gs.getGlobal().getSettings().getCharset() ) );
//get the feature collection
FeatureCollection<?, ?> fc =
featureCollection.getFeature().get(0);
if (fc.getSchema() instanceof SimpleFeatureType) {
//write out the header
SimpleFeatureType ft = (SimpleFeatureType) fc.getSchema();
w.write("FID,");
for ( int i = 0; i < ft.getAttributeCount(); i++ ) {
AttributeDescriptor ad = ft.getDescriptor( i );
w.write( prepCSVField(ad.getLocalName()) );
if ( i < ft.getAttributeCount()-1 ) {
w.write( "," );
}
}
} else {
// complex features
w.write("gml:id,");
int i = 0;
for (PropertyDescriptor att : fc.getSchema().getDescriptors()) {
// exclude temporary attributes
if (!att.getName().getLocalPart().startsWith("FEATURE_LINK")) {
if (i > 0) {
w.write(",");
}
String elName = att.getName().toString();
Object xsd = att.getUserData().get(XSDElementDeclaration.class);
if (xsd != null && xsd instanceof XSDElementDeclarationImpl) {
// get the prefixed name if possible
// otherwise defaults to the full name with namespace URI
XSDElementDeclarationImpl xsdEl = (XSDElementDeclarationImpl) xsd;
elName = xsdEl.getQName();
}
w.write(prepCSVField(elName));
i++;
}
}
}
// by RFC each line is terminated by CRLF
w.write( "\r\n" );
// prepare the formatter for numbers
NumberFormat coordFormatter = NumberFormat.getInstance(Locale.US);
coordFormatter.setMaximumFractionDigits(getInfo().getGeoServer().getSettings().getNumDecimals());
coordFormatter.setGroupingUsed(false);
//write out the features
FeatureIterator<?> i = fc.features();
try {
while( i.hasNext() ) {
Feature f = i.next();
// dump fid
w.write(prepCSVField(f.getIdentifier().getID()));
w.write(",");
if (f instanceof SimpleFeature) {
// dump attributes
for ( int j = 0; j < ((SimpleFeature) f).getAttributeCount(); j++ ) {
Object att = ((SimpleFeature) f).getAttribute( j );
if ( att != null ) {
String value = formatToString(att, coordFormatter);
w.write( prepCSVField(value) );
}
if ( j < ((SimpleFeature) f).getAttributeCount()-1 ) {
w.write(",");
}
}
} else {
// complex feature
Iterator<PropertyDescriptor> descriptors = fc.getSchema().getDescriptors().iterator();
// dump attributes
int j = 0;
while (descriptors.hasNext()) {
PropertyDescriptor desc = descriptors.next();
if (desc.getName().getLocalPart().startsWith("FEATURE_LINK")) {
// skip temporary attributes
continue;
}
if (j > 0) {
w.write(",");
}
j++;
// Multi valued properties aren't supported, only for SF0 for now
Collection<Property> values = f.getProperties(desc.getName());
if (values.size() > 1) {
throw new UnsupportedOperationException(
"Multi valued properties aren't supported with CSV format!");
}
Object att = null;
if (!values.isEmpty()) {
att = values.iterator().next().getValue();
}
if (att != null) {
String value = formatToString(att, coordFormatter);
w.write(prepCSVField(value));
}
}
}
// by RFC each line is terminated by CRLF
w.write("\r\n");
}
} finally {
i.close();
}
w.flush();
}
private String formatToString(Object att, NumberFormat coordFormatter) {
String value = null;
if (att instanceof Number) {
// don't allow scientific notation in the output, as OpenOffice won't
// recognize that as a number
value = coordFormatter.format(att);
} else if (att instanceof Date) {
// serialize dates in ISO format
if (att instanceof java.sql.Date)
value = DateUtil.serializeSqlDate((java.sql.Date) att);
else if (att instanceof java.sql.Time)
value = DateUtil.serializeSqlTime((java.sql.Time) att);
else
value = DateUtil.serializeDateTime((Date) att);
} else {
// everything else we just "toString"
value = att.toString();
}
return value;
}
/*
* The CSV "spec" explains that fields with certain properties must be
* delimited by double quotes, and also that double quotes within fields
* must be escaped. This method takes a field and returns one that
* obeys the CSV spec.
*/
private String prepCSVField(String field){
// "embedded double-quote characters must be represented by a pair of double-quote characters."
String mod = field.replaceAll("\"", "\"\"");
/*
* Enclose string in double quotes if it contains double quotes, commas, or newlines
*/
if (CSV_ESCAPES.matcher(mod).find()) {
mod = "\"" + mod + "\"";
}
return mod;
}
@Override
public String getCapabilitiesElementName() {
return "CSV";
}
@Override
public String getCharset(Operation operation){
return gs.getGlobal().getSettings().getCharset();
}
}