package org.gcube.data.analysis.wps;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.UUID;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.lang.StringUtils;
import org.gcube.data.analysis.wps.processes.Processes;
import org.n52.wps.commons.XMLUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class CancelComputation extends HttpServlet {
private final static Logger LOGGER = LoggerFactory.getLogger(CancelComputation.class);
private static final long serialVersionUID = -268198171054599696L;
// This is required for URL generation for response documents.
public final static String SERVLET_PATH = "CancelComputationServlet";
// in future parameterize
//private final boolean indentXML = false;
private final int uuid_length = 36;
@Override
public void init(ServletConfig config) throws ServletException {
super.init(config);
}
public static String empty = " " +
" " +
"";
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// id of result to retrieve.
String id = request.getParameter("id");
LOGGER.debug("CANCEL COMPUTATION -> RETRIEVING ID {}", id);
if (StringUtils.isEmpty(id)) {
errorResponse("id parameter missing", response);
} else {
LOGGER.debug("CANCEL COMPUTATION -> ID {} RETRIEVED ", id);
if (!isIDValid(id)) {
errorResponse("id parameter not valid", response);
}
LOGGER.debug("CANCEL COMPUTATION -> ID {} IS VALID ",id);
/*IDatabase db = DatabaseFactory.getDatabase();
long len = db.getContentLengthForStoreResponse(id);
LOGGER.debug("CANCEL COMPUTATION -> INITIAL ID RESPONSE LENGTH " + len);
try {
LOGGER.debug("CANCEL COMPUTATION -> DELETING ID " + id);
try {
// String empty = "";
InputStream stream = new ByteArrayInputStream(empty.getBytes("UTF-8"));
db.updateResponse(id, stream);
stream.close();
} catch (Exception e) {
LOGGER.error("error reading th einput stream",e);
}
LOGGER.debug("CANCEL COMPUTATION -> ID DELETED " + id);
len = db.getContentLengthForStoreResponse(id);
LOGGER.debug("CANCEL COMPUTATION -> ID RESPONSE LENGTH " + len);
} catch (Exception e) {
LOGGER.error("error in do get",e);
} finally {
}*/
if (Processes.getRunningProcesses().containsKey(id)){
boolean cancelled = Processes.getRunningProcesses().get(id).cancel();
if(!cancelled)
LOGGER.debug("CANCEL COMPUTATION -> process with id {} already cancelled ", id);
} else LOGGER.debug("CANCEL COMPUTATION -> no running process with id {} (probably it already finished) ", id);
}
}
protected void errorResponse(String error, HttpServletResponse response) throws IOException {
response.setContentType("text/html");
response.setStatus(HttpServletResponse.SC_BAD_REQUEST);
PrintWriter writer = response.getWriter();
writer.write("Error" + error + "");
writer.flush();
LOGGER.warn("Error processing response: " + error);
}
protected void copyResponseStream(InputStream inputStream, OutputStream outputStream, String id, long contentLength) throws IOException {
long contentWritten = 0;
try {
byte[] buffer = new byte[8192];
int bufferRead;
while ((bufferRead = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, bufferRead);
contentWritten += bufferRead;
}
} catch (IOException e) {
String exceptionMessage = contentLength > -1 ? String.format("Error writing response to output stream for id %s, %d of %d bytes written", id, contentWritten, contentLength) : String.format("Error writing response to output stream for id %s, %d bytes written", id, contentWritten);
throw new IOException(exceptionMessage, e);
}
LOGGER.info("{} bytes written in response to id {}", contentWritten, id);
}
protected void copyResponseAsXML(InputStream inputStream, OutputStream outputStream, boolean indent, String id) throws IOException {
try {
XMLUtil.copyXML(inputStream, outputStream, indent);
} catch (IOException e) {
throw new IOException("Error writing XML response for id " + id, e);
}
}
public static Throwable getRootCause(Throwable t) {
return t.getCause() == null ? t : getRootCause(t.getCause());
}
public boolean isIDValid(String id) {
if (id.length() <= uuid_length) {
try {
UUID checkUUID = UUID.fromString(id);
if (checkUUID.toString().equals(id)) {
return true;
} else {
return false;
}
} catch (Exception e) {
return false;
}
} else {
String uuidPartOne = id.substring(0, uuid_length);
String uuidPartTwo = id.substring(id.length() - uuid_length, id.length());
return isUUIDValid(uuidPartOne) && isUUIDValid(uuidPartTwo);
}
}
public boolean isUUIDValid(String uuid) {
// the following can be used to check whether the id is a valid UUID
try {
UUID checkUUID = UUID.fromString(uuid);
if (checkUUID.toString().equals(uuid)) {
return true;
} else {
return false;
}
} catch (Exception e) {
return false;
}
}
}