HotfolderManager.java

package de.uni_goettingen.sub.commons.ocr.abbyy.server;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import de.uni_goettingen.sub.commons.ocr.abbyy.server.hotfolder.Hotfolder;
import de.uni_goettingen.sub.commons.ocr.abbyy.server.hotfolder.HotfolderProvider;
import de.uni_goettingen.sub.commons.ocr.api.OcrImage;
import de.uni_goettingen.sub.commons.ocr.api.OcrOutput;
import de.unigoettingen.sub.commons.ocr.util.Pause;

public class HotfolderManager {
	private final static Logger logger = LoggerFactory.getLogger(HotfolderManager.class);
	private Hotfolder hotfolder;
	static Object monitor = new Object();
	private HotfolderProvider hotfolderProvider = new HotfolderProvider();
	private Pause pause = new Pause();
	private XmlParser xmlParser = new XmlParser();

	public HotfolderManager(String serverUrl, String user, String password) {
		hotfolder = hotfolderProvider.createHotfolder(serverUrl, user, password);
	}
	
	// for unit tests
	HotfolderManager(Hotfolder initHotfolder) {
		hotfolder = initHotfolder;
	}
	void setPause(Pause newPause) {
		pause = newPause;
	}
	void setXmlParser(XmlParser newParser) {
		xmlParser = newParser;
	}

	public void deleteOutputs(List<OcrOutput> outputs) throws IOException {
		for (OcrOutput out : outputs) {
			AbbyyOutput abbyyOut = (AbbyyOutput) out;
			URI remoteUri = abbyyOut.getRemoteUri();
			hotfolder.deleteIfExists(remoteUri);
		}
	}

	public void deleteImages(List<OcrImage> images) throws IOException {
		for (OcrImage ocrImage : images) {
			AbbyyImage image = (AbbyyImage) ocrImage;
			URI remoteUri = image.getRemoteUri();
			hotfolder.deleteIfExists(remoteUri);
			URI errorImageUri = image.getErrorUri();
			hotfolder.deleteIfExists(errorImageUri);
		}
	}

	public void copyImagesToHotfolder(List<OcrImage> ocrImages) throws IOException {
		for (OcrImage ocrImage : ocrImages) {
			AbbyyImage image = (AbbyyImage) ocrImage;
			URI fromUri = image.getLocalUri();
			URI toUri = image.getRemoteUri();
			hotfolder.upload(fromUri, toUri);
		}
	}

	public void retrieveResults(List<OcrOutput> ocrOutputs) throws IOException {
		for (OcrOutput entry : ocrOutputs) {
			AbbyyOutput o = (AbbyyOutput) entry;

			URI remoteUri = o.getRemoteUri();
			URI localUri = o.getLocalUri();
			hotfolder.download(remoteUri, localUri);
			hotfolder.deleteIfExists(remoteUri);
		}
	}

	public void createAndSendTicket(AbbyyTicket abbyyTicket, String name) throws IOException, URISyntaxException {
		String ticketFileName = name + ".xml";
		URI inputTicketUri = abbyyTicket.getRemoteInputUri();
	
		OutputStream os = hotfolder.createTmpFile(ticketFileName);
		abbyyTicket.write(os);
		if (os != null)
			os.close();
		
		//TODO: remove
//		URI ticketLogPath = new java.io.File("/home/dennis/temp/tickets/" + ticketFileName).toURI();
//		hotfolder.copyTmpFile(ticketFileName, ticketLogPath);

		hotfolder.copyTmpFile(ticketFileName, inputTicketUri);
		hotfolder.deleteTmpFile(ticketFileName);
	}

	public void waitForResults(long timeout, long waitInterval,
			List<OcrOutput> outputs, URI errorResultXmlUri) throws TimeoutException, IOException {		
		long start = System.currentTimeMillis();
		
		List<URI> mustBeThereUris = extractFromOutputs(outputs);
		
		outerLoop:
		while (true) {

			checkIfError(start, timeout, errorResultXmlUri);

			for (URI expectedUri : mustBeThereUris) {
				if (!hotfolder.exists(expectedUri)) {
					logger.debug(expectedUri.toString() + " is not yet available");
					waitALittle(waitInterval);
					continue outerLoop;
				}
			}
			logger.debug("Got all files.");
			break;
		}
	}

	private List<URI> extractFromOutputs(List<OcrOutput> outputs) {
		List<URI> mustBeThereUris = new ArrayList<URI>();
		for (OcrOutput out : outputs) {
			final AbbyyOutput output = (AbbyyOutput) out;
			URI uri = output.getRemoteUri();
			mustBeThereUris.add(uri);
		}
		return mustBeThereUris;
	}
	
	private void checkIfError(long start, long timeout, URI errorResultXmlUri) throws TimeoutException, IOException {
		if (System.currentTimeMillis() > start + timeout) {
			logger.error("Waited too long for results.");
			throw new TimeoutException("Waited too long for results.");
		}
		if (hotfolder.exists(errorResultXmlUri)) {
			logger.error("Server reported an OCR error in file: " + errorResultXmlUri);
			throw new IOException("Server reported an OCR error in file: " + errorResultXmlUri);
		}
	}
	
	private void waitALittle(long waitInterval) {
		logger.debug("Waiting for " + waitInterval
				+ " milli seconds (" + waitInterval/1000/60 + " minutes)");
		pause.forMilliseconds(waitInterval);
	}

	public boolean enoughSpaceAvailable(long maxSpace, URI inputFolder,
		URI outputFolder, URI errorFolder) throws IOException {
		long totalFileSize = hotfolder.getUsedSpace(inputFolder) 
				+ hotfolder.getUsedSpace(outputFolder) 
				+ hotfolder.getUsedSpace(errorFolder);

		logger.debug("TotalFileSize = " + totalFileSize);
		if (totalFileSize >= maxSpace) {
			logger.warn("Size of files is too high. Allowed space for all files is "
					+ maxSpace
					+ ". Size of files in hotfolder: "
					+ totalFileSize + ".");
			return false;
		} else {
			return true;
		}
		
	}

	public void deleteTicket(AbbyyTicket abbyyTicket) throws IOException, URISyntaxException {
		hotfolder.deleteIfExists(abbyyTicket.getRemoteInputUri());
		hotfolder.deleteIfExists(abbyyTicket.getRemoteErrorUri());
	}

	public String readFromErrorFile(URI errorResultUri, String processName) {
		String errorDescription = "";
		logger.debug("Trying to parse file " + errorResultUri + " (" + processName + ")");
		try {
			if (hotfolder.exists(errorResultUri)) {
				InputStream is = new ByteArrayInputStream(hotfolder.getResponse(errorResultUri));
				errorDescription = xmlParser.readErrorFromResultXml(is, processName);
				//hotfolder.deleteIfExists(errorResultUri);
			}
		} catch (IOException e) {
			logger.warn("Could not read the error from file " + errorResultUri);
		}
		return errorDescription;
	}

	
}