package org.archive.wayback.memento;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Properties;
import javax.servlet.http.HttpServletResponse;
import org.archive.wayback.core.CaptureSearchResult;
import org.archive.wayback.core.CaptureSearchResults;
import org.archive.wayback.core.WaybackRequest;
import org.archive.wayback.partition.NotableResultExtractor;
import org.archive.wayback.util.ObjectFilterIterator;
import org.archive.wayback.util.StringFormatter;
import org.archive.wayback.webapp.AccessPoint;
public class MementoUtils implements MementoConstants {
public final static SimpleDateFormat HTTP_LINK_DATE_FORMATTER;
public final static SimpleDateFormat DATE_FORMAT_14_FORMATTER;
static {
HTTP_LINK_DATE_FORMATTER = new SimpleDateFormat(HTTP_LINK_DATE_FORMAT, Locale.ENGLISH);
HTTP_LINK_DATE_FORMATTER.setTimeZone(GMT_TZ);
DATE_FORMAT_14_FORMATTER = new SimpleDateFormat(DATE_FORMAT_14, Locale.ENGLISH);
DATE_FORMAT_14_FORMATTER.setTimeZone(GMT_TZ);
}
public static void printTimemapResponse(CaptureSearchResults results, WaybackRequest wbRequest, HttpServletResponse response) throws IOException
{
response.setContentType("application/link-format");
printLinkTimemap(results, wbRequest, response.getWriter());
}
public static void printLinkTimemap(CaptureSearchResults results,
WaybackRequest wbr, PrintWriter pw) {
Date first = results.getFirstResultDate();
Date last = results.getLastResultDate();
AccessPoint ap = wbr.getAccessPoint();
String requestUrl = wbr.getRequestUrl();
// ludab nov30 2012
String pagedate = wbr.get(PAGE_STARTS);
if (pagedate == null) {
pagedate = "";
} else {
pagedate = pagedate + "/";
}
// end
pw.print(makeLink(requestUrl, ORIGINAL));
pw.println(",");
// ludab nov 30 2012
// pw.print(makeLink(getTimemapUrl(ap,FORMAT_LINK,requestUrl),
// TIMEMAP,APPLICATION_LINK_FORMAT));
pw.print(makeLink(
getTimemapDateUrl(ap, FORMAT_LINK, pagedate, requestUrl),
"self", APPLICATION_LINK_FORMAT)
+ "; from=\""
+ HTTP_LINK_DATE_FORMATTER.format(first)
+ "\""
+ "; until=\""
+ HTTP_LINK_DATE_FORMATTER.format(last) + "\"");
// end
pw.println(",");
pw.print(makeLink(getTimegateUrl(ap, requestUrl), TIMEGATE));
pw.println(",");
if (first.compareTo(last) == 0) {
// special handling of single result:
CaptureSearchResult result = results.getResults().get(0);
pw.print(makeLink(ap, result.getOriginalUrl(), FIRST_LAST_MEMENTO, result));
} else {
List<CaptureSearchResult> lr = results.getResults();
int count = lr.size();
String rel;
for (int i = 0; i < count; i++) {
CaptureSearchResult result = lr.get(i);
if (i == 0) {
rel = FIRST_MEMENTO;
} else if (i == count - 1) {
pw.println(",");
rel = LAST_MEMENTO;
} else {
pw.println(",");
rel = MEMENTO;
}
pw.print(makeLink(ap, result.getOriginalUrl(), rel,
result));
}
}
// ludab nov 30 2012
if (results.getMatchingCount() > results.getReturnedCount()) {
int sec = last.getSeconds() + 1;
last.setSeconds(sec);
pw.println(",");
pw.print(makeLink(
getTimemapDateUrl(ap, FORMAT_LINK,
DATE_FORMAT_14_FORMATTER.format(last) + "/",
requestUrl), TIMEMAP, APPLICATION_LINK_FORMAT)
+ "; from=\""
+ HTTP_LINK_DATE_FORMATTER.format(last)
+ "\"");
}
// end
pw.flush();
}
public static String generateMementoLinkHeaders(
CaptureSearchResults results, WaybackRequest wbr, boolean includeTimegateLink, boolean includeOriginalLink) {
NotableResultExtractor nre = getNotableResults(results);
CaptureSearchResult first = nre.getFirst();
CaptureSearchResult prev = nre.getPrev();
CaptureSearchResult closest = nre.getClosest();
CaptureSearchResult next = nre.getNext();
CaptureSearchResult last = nre.getLast();
ArrayList<String> rels = new ArrayList<String>();
AccessPoint ap = wbr.getAccessPoint();
String requestUrl = wbr.getRequestUrl();
// add generics:
// rels.add(makeLink(getTimebundleUrl(ap, requestUrl), TIMEBUNDLE));
if (includeOriginalLink) {
rels.add(makeLink(requestUrl, ORIGINAL));
}
rels.add(makeLink(getTimemapUrl(ap, FORMAT_LINK, requestUrl), TIMEMAP,
APPLICATION_LINK_FORMAT));
// Spec says not to include timegate link for timegate
if (includeTimegateLink) {
rels.add(makeLink(getTimegateUrl(ap, requestUrl), TIMEGATE));
}
// add first/prev/next/last:
if (first == last) {
// only one capture.. are we sure we want the "actual" memento here?
rels.add(makeLink(ap, requestUrl, FIRST_LAST_MEMENTO,
first));
} else {
if (first == closest) {
// no previous:
rels.add(makeLink(ap, requestUrl, FIRST_MEMENTO,
first));
if (next == last) {
rels.add(makeLink(ap, requestUrl, NEXT_LAST_MEMENTO,
last));
} else {
rels.add(makeLink(ap, requestUrl, NEXT_MEMENTO,
next));
rels.add(makeLink(ap, requestUrl, LAST_MEMENTO,
last));
}
} else if (last == closest) {
// no next:
rels.add(makeLink(ap, requestUrl, LAST_MEMENTO,
last));
if (prev == first) {
rels.add(makeLink(ap, requestUrl, PREV_FIRST_MEMENTO,
first));
} else {
rels.add(makeLink(ap, requestUrl, FIRST_MEMENTO,
first));
rels.add(makeLink(ap, requestUrl, PREV_MEMENTO,
prev));
}
} else {
// somewhere in the middle:
if (prev == first) {
rels.add(makeLink(ap, requestUrl, PREV_FIRST_MEMENTO,
first));
} else {
// add both prev and first:
rels.add(makeLink(ap, requestUrl, FIRST_MEMENTO,
first));
rels.add(makeLink(ap, requestUrl, PREV_MEMENTO,
prev));
}
// add "actual" memento:
rels.add(makeLink(ap, requestUrl, MEMENTO,
closest));
if (next == last) {
rels.add(makeLink(ap, requestUrl, NEXT_LAST_MEMENTO,
last));
} else {
rels.add(makeLink(ap, requestUrl, NEXT_MEMENTO,
next));
rels.add(makeLink(ap, requestUrl, LAST_MEMENTO,
last));
}
}
}
return StringFormatter.join(", ", rels.toArray(a));
}
static String[] a = new String[0];
public static void addVaryHeader(HttpServletResponse response) {
response.setHeader(VARY, NEGOTIATE_DATETIME);
}
public static boolean hasLinkHeader(HttpServletResponse response) {
// HRM.. Are we sure it's *our* Link header, and has the rel="original"?
return response.containsHeader(LINK);
}
public static void addOrigHeader(HttpServletResponse response, String url) {
response.setHeader(LINK, makeLink(url, ORIGINAL));
}
public static void addDoNotNegotiateHeader(HttpServletResponse response) {
// New Non-Negotiate header
// Link: <http://mementoweb.org/terms/donotnegotiate">; rel="type"
response.setHeader(LINK, makeLink("http://mementoweb.org/terms/donotnegotiate", "type"));
}
public static void addOrigHeader(HttpServletResponse response,
WaybackRequest wbr) {
addOrigHeader(response, wbr.getRequestUrl());
}
public static String makeOrigHeader(String url)
{
return makeLink(url, ORIGINAL);
}
public static void addMementoHeaders(HttpServletResponse response,
CaptureSearchResults results, CaptureSearchResult result, WaybackRequest wbr) {
response.setHeader(MEMENTO_DATETIME, HTTP_LINK_DATE_FORMATTER
.format(results.getClosest().getCaptureDate()));
if (!wbr.isMementoTimegate()) {
response.setHeader(LINK, generateMementoLinkHeaders(results, wbr, true, true));
}
}
public static void addTimegateHeaders(HttpServletResponse response,
CaptureSearchResults results, WaybackRequest wbr, boolean includeOriginal) {
addVaryHeader(response);
response.setHeader(LINK, generateMementoLinkHeaders(results, wbr, false, includeOriginal));
}
// private static String getTimegatePrefix(AccessPoint ap) {
// // if(ap.getClass().isAssignableFrom(MementoAccessPoint.class)) {
// String prefix = null;
// if (ap instanceof MementoAccessPoint) {
// prefix = ((MementoAccessPoint) ap).getTimegatePrefix();
// }
// if (prefix == null) {
// prefix = getProp(ap.getConfigs(), TIMEGATE_PREFIX_CONFIG, null);
// }
// // TODO: rationalize...
// if (prefix == null) {
// prefix = ap.getReplayPrefix();
// }
// return prefix;
// }
public static final SimpleDateFormat ACCEPT_DATE_FORMATS[] = {
new SimpleDateFormat("E, dd MMM yyyy HH:mm:ss Z", Locale.ENGLISH),
new SimpleDateFormat("E, dd MMM yyyy Z", Locale.ENGLISH),
new SimpleDateFormat("E, dd MMM yyyy", Locale.ENGLISH) };
public static Date parseAcceptDateTimeHeader(String datespec) {
for (SimpleDateFormat format : ACCEPT_DATE_FORMATS) {
try {
return format.parse(datespec);
} catch (ParseException e) {
// ignore and move on..
}
}
return null;
}
public static String getTimegateUrl(AccessPoint ap, String url) {
StringBuilder sb = new StringBuilder();
sb.append(getTimeGatePrefix(ap));
sb.append(url);
return sb.toString();
}
public static String getTimemapUrl(AccessPoint ap, String format, String url) {
StringBuilder sb = new StringBuilder();
sb.append(getTimeMapPrefix(ap));
sb.append(TIMEMAP).append("/").append(format).append("/");
sb.append(url);
return sb.toString();
}
public static String getTimemapDateUrl(AccessPoint ap, String format,
String pagestr, String url) {
StringBuilder sb = new StringBuilder();
sb.append(getTimeMapPrefix(ap));
sb.append(TIMEMAP).append("/").append(format).append("/");
sb.append(pagestr);
sb.append(url);
return sb.toString();
}
public static String getTimeMapPrefix(AccessPoint ap) {
return getMementoPrefix(ap) + ap.getQueryPrefix();
}
public static String getTimeGatePrefix(AccessPoint ap) {
return getMementoPrefix(ap) + ap.getReplayPrefix();
}
public static String getMementoPrefix(AccessPoint ap) {
return getProp(ap.getConfigs(), AGGREGATION_PREFIX_CONFIG, "");
// String prefix = null;
// if (ap instanceof MementoAccessPoint) {
// prefix = ((MementoAccessPoint) ap).getTimegatePrefix();
// }
// // TODO: rationalize...
// if (prefix == null) {
// prefix = getProp(ap.getConfigs(), AGGREGATION_PREFIX_CONFIG, "");
// }
// if (prefix == null) {
// prefix = ap.getQueryPrefix();
// }
// return prefix;
}
public static int getPageMaxRecord(AccessPoint ap) {
String mr;
mr = getProp(ap.getConfigs(), PAGE_MAXRECORDS_CONFIG, "0");
if (mr == null) {
mr = "0";
}
return new Integer(mr).intValue();
}
private static String getProp(Properties p, String name, String deflt) {
if (p == null) {
return deflt;
}
return p.getProperty(name, deflt);
}
private static String makeLink(String url, String rel) {
return String.format("<%s>; rel=\"%s\"", url, rel);
}
private static String makeLink(String url, String rel, String type) {
return String.format("<%s>; rel=\"%s\"; type=\"%s\"", url, rel, type);
}
private static String makeLink(AccessPoint ap, String url, String rel, CaptureSearchResult result) {
Date date = result.getCaptureDate();
String timestamp = DATE_FORMAT_14_FORMATTER.format(date);
String replayURI = ap.getUriConverter().makeReplayURI(timestamp, url);
String prefix = getMementoPrefix(ap);
String httpTime = HTTP_LINK_DATE_FORMATTER.format(date);
// return String.format("<%s%s>; rel=\"%s\"; datetime=\"%s\"; status=\"%s\"", prefix, replayURI,
// rel, httpTime, result.getHttpCode());
return String.format("<%s%s>; rel=\"%s\"; datetime=\"%s\"", prefix, replayURI, rel, httpTime);
}
private static NotableResultExtractor getNotableResults(
CaptureSearchResults r) {
// eventually, the NotableResultExtractor will be part of the standard
// ResourceIndex.query() but for now, we'll just do an extra traversal
// of the whole set of results:
Iterator<CaptureSearchResult> itr = r.iterator();
Date want = r.getClosest().getCaptureDate();
NotableResultExtractor nre = new NotableResultExtractor(want);
ObjectFilterIterator<CaptureSearchResult> ofi = new ObjectFilterIterator<CaptureSearchResult>(
itr, nre);
while (ofi.hasNext()) {
ofi.next();
}
return nre;
}
}