/*
* This file is part of the Heritrix web crawler (crawler.archive.org).
*
* Licensed to the Internet Archive (IA) by one or more individual
* contributors.
*
* The IA licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.archive.modules.extractor;
import java.io.IOException;
import java.io.InputStream;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.commons.io.IOUtils;
import org.archive.modules.CrawlURI;
import org.archive.net.UURI;
import org.archive.net.UURIFactory;
/**
* A last ditch extractor that will look at the raw byte code and try to extract
* anything that <i>looks</i> like a link.
*
* If used, it should always be specified as the last link extractor in the
* order file.
* <p>
* To accomplish this it will scan through the bytecode and try and build up
* strings of consecutive bytes that all represent characters that are valid
* in a URL (see #isURLableChar(int) for details).
* Once it hits the end of such a string (i.e. finds a character that
* should not be in a URL) it will try to determine if it has found a URL.
* This is done be seeing if the string is an IP address prefixed with
* http(s):// or contains a dot followed by a Top Level Domain and end of
* string or a slash.
*
* @author Kristinn Sigurdsson
*/
public class ExtractorUniversal extends ContentExtractor {
@SuppressWarnings("unused")
private static final long serialVersionUID = 3L;
/**
* How deep to look into files for URI strings, in bytes.
*/
{
setMaxSizeToParse(1*1024*1024L); // 1MB
}
public long getMaxSizeToParse() {
return (Long) kp.get("maxSizeToParse");
}
public void setMaxSizeToParse(long threshold) {
kp.put("maxSizeToParse",threshold);
}
/**
* Matches any string that begins with http:// or https:// followed by
* something that looks like an ip address (four numbers, none longer then
* 3 chars seperated by 3 dots). Does <b>not</b> ensure that the numbers are
* each in the range 0-255.
*/
protected static final Pattern IP_ADDRESS = Pattern.compile(
"((http://)|(https://))(\\d(\\d)?(\\d)?\\.\\d(\\d)?(\\d)?\\.\\d(\\d)?(\\d)?\\.\\d(\\d)?(\\d)?)");
/**
* Matches any string that begins with a TLD (no .) followed by a '/' slash
* or end of string. If followed by slash then nothing after the slash is
* of consequence.
*/
public static final Pattern TLDs = Pattern.compile(
"(ac(/.*)?)" // ac Ascension Island
+ "|(ad(/.*)?)" // ad Andorra
+ "|(ae(/.*)?)" // ae United Arab Emirates
+ "|(af(/.*)?)" // af Afghanistan
+ "|(ag(/.*)?)" // ag Antigua and Barbuda
+ "|(ai(/.*)?)" // ai Anguilla
+ "|(al(/.*)?)" // al Albania
+ "|(am(/.*)?)" // am Armenia
+ "|(an(/.*)?)" // an Netherlands Antilles
+ "|(ao(/.*)?)" // ao Angola
+ "|(aero(/.*)?)" // aero Air-transport industry
+ "|(aq(/.*)?)" // aq Antarctica
+ "|(ar(/.*)?)" // ar Argentina
+ "|(as(/.*)?)" // as American Samoa
+ "|(at(/.*)?)" // at Austria
+ "|(au(/.*)?)" // au Australia
+ "|(aw(/.*)?)" // aw Aruba
+ "|(az(/.*)?)" // az Azerbaijan
+ "|(ba(/.*)?)" // ba Bosnia Hercegovina
+ "|(bb(/.*)?)" // bb Barbados
+ "|(bd(/.*)?)" // bd Bangladesh
+ "|(be(/.*)?)" // be Belgium
+ "|(bf(/.*)?)" // bf Burkina Faso
+ "|(bg(/.*)?)" // bg Bulgaria
+ "|(bh(/.*)?)" // bh Bahrain
+ "|(bi(/.*)?)" // bi Burundi
+ "|(biz(/.*)?)" // biz Businesses
+ "|(bj(/.*)?)" // bj Benin
+ "|(bm(/.*)?)" // bm Bermuda
+ "|(bn(/.*)?)" // bn Brunei Darussalam
+ "|(bo(/.*)?)" // bo Bolivia
+ "|(br(/.*)?)" // br Brazil
+ "|(bs(/.*)?)" // bs Bahamas
+ "|(bt(/.*)?)" // bt Bhutan
+ "|(bv(/.*)?)" // bv Bouvet Island
+ "|(bw(/.*)?)" // bw Botswana
+ "|(by(/.*)?)" // by Belarus (Byelorussia)
+ "|(bz(/.*)?)" // bz Belize
+ "|(ca(/.*)?)" // ca Canada
+ "|(cc(/.*)?)" // cc Cocos Islands (Keeling)
+ "|(cd(/.*)?)" // cd Congo, Democratic Republic of the
+ "|(cf(/.*)?)" // cf Central African Republic
+ "|(cg(/.*)?)" // cg Congo, Republic of
+ "|(ch(/.*)?)" // ch Switzerland
+ "|(ci(/.*)?)" // ci Cote d'Ivoire (Ivory Coast)
+ "|(ck(/.*)?)" // ck Cook Islands
+ "|(cl(/.*)?)" // cl Chile
+ "|(cm(/.*)?)" // cm Cameroon
+ "|(cn(/.*)?)" // cn China
+ "|(co(/.*)?)" // co Colombia
+ "|(com(/.*)?)" // com Commercial
+ "|(coop(/.*)?)" // coop Cooperatives
+ "|(cr(/.*)?)" // cr Costa Rica
+ "|(cs(/.*)?)" // cs Czechoslovakia
+ "|(cu(/.*)?)" // cu Cuba
+ "|(cv(/.*)?)" // cv Cap Verde
+ "|(cx(/.*)?)" // cx Christmas Island
+ "|(cy(/.*)?)" // cy Cyprus
+ "|(cz(/.*)?)" // cz Czech Republic
+ "|(de(/.*)?)" // de Germany
+ "|(dj(/.*)?)" // dj Djibouti
+ "|(dk(/.*)?)" // dk Denmark
+ "|(dm(/.*)?)" // dm Dominica
+ "|(do(/.*)?)" // do Dominican Republic
+ "|(dz(/.*)?)" // dz Algeria
+ "|(ec(/.*)?)" // ec Ecuador
+ "|(edu(/.*)?)" // edu Educational Institution
+ "|(ee(/.*)?)" // ee Estonia
+ "|(eg(/.*)?)" // eg Egypt
+ "|(eh(/.*)?)" // eh Western Sahara
+ "|(er(/.*)?)" // er Eritrea
+ "|(es(/.*)?)" // es Spain
+ "|(et(/.*)?)" // et Ethiopia
+ "|(fi(/.*)?)" // fi Finland
+ "|(fj(/.*)?)" // fj Fiji
+ "|(fk(/.*)?)" // fk Falkland Islands
+ "|(fm(/.*)?)" // fm Micronesia, Federal State of
+ "|(fo(/.*)?)" // fo Faroe Islands
+ "|(fr(/.*)?)" // fr France
+ "|(ga(/.*)?)" // ga Gabon
+ "|(gd(/.*)?)" // gd Grenada
+ "|(ge(/.*)?)" // ge Georgia
+ "|(gf(/.*)?)" // gf French Guiana
+ "|(gg(/.*)?)" // gg Guernsey
+ "|(gh(/.*)?)" // gh Ghana
+ "|(gi(/.*)?)" // gi Gibraltar
+ "|(gl(/.*)?)" // gl Greenland
+ "|(gm(/.*)?)" // gm Gambia
+ "|(gn(/.*)?)" // gn Guinea
+ "|(gov(/.*)?)" // gov Government (US)
+ "|(gp(/.*)?)" // gp Guadeloupe
+ "|(gq(/.*)?)" // gq Equatorial Guinea
+ "|(gr(/.*)?)" // gr Greece
+ "|(gs(/.*)?)" // gs South Georgia and the South Sandwich Islands
+ "|(gt(/.*)?)" // gt Guatemala
+ "|(gu(/.*)?)" // gu Guam
+ "|(gw(/.*)?)" // gw Guinea-Bissau
+ "|(gy(/.*)?)" // gy Guyana
+ "|(hk(/.*)?)" // hk Hong Kong
+ "|(hm(/.*)?)" // hm Heard and McDonald Islands
+ "|(hn(/.*)?)" // hn Honduras
+ "|(hr(/.*)?)" // hr Croatia/Hrvatska
+ "|(ht(/.*)?)" // ht Haiti
+ "|(hu(/.*)?)" // hu Hungary
+ "|(id(/.*)?)" // id Indonesia
+ "|(ie(/.*)?)" // ie Ireland
+ "|(il(/.*)?)" // il Israel
+ "|(im(/.*)?)" // im Isle of Man
+ "|(in(/.*)?)" // in India
+ "|(info(/.*)?)" // info
+ "|(int(/.*)?)" // int Int. Organizations
+ "|(io(/.*)?)" // io British Indian Ocean Territory
+ "|(iq(/.*)?)" // iq Iraq
+ "|(ir(/.*)?)" // ir Iran, Islamic Republic of
+ "|(is(/.*)?)" // is Iceland
+ "|(it(/.*)?)" // it Italy
+ "|(je(/.*)?)" // je Jersey
+ "|(jm(/.*)?)" // jm Jamaica
+ "|(jo(/.*)?)" // jo Jordan
+ "|(jp(/.*)?)" // jp Japan
+ "|(ke(/.*)?)" // ke Kenya
+ "|(kg(/.*)?)" // kg Kyrgyzstan
+ "|(kh(/.*)?)" // kh Cambodia
+ "|(ki(/.*)?)" // ki Kiribati
+ "|(km(/.*)?)" // km Comoros
+ "|(kn(/.*)?)" // kn Saint Kitts and Nevis
+ "|(kp(/.*)?)" // kp Korea, Democratic People's Republic
+ "|(kr(/.*)?)" // kr Korea, Republic of
+ "|(kw(/.*)?)" // kw Kuwait
+ "|(ky(/.*)?)" // ky Cayman Islands
+ "|(kz(/.*)?)" // kz Kazakhstan
+ "|(la(/.*)?)" // la Lao People's Democratic Republic
+ "|(lb(/.*)?)" // lb Lebanon
+ "|(lc(/.*)?)" // lc Saint Lucia
+ "|(li(/.*)?)" // li Liechtenstein
+ "|(lk(/.*)?)" // lk Sri Lanka
+ "|(lr(/.*)?)" // lr Liberia
+ "|(ls(/.*)?)" // ls Lesotho
+ "|(lt(/.*)?)" // lt Lithuania
+ "|(lu(/.*)?)" // lu Luxembourg
+ "|(lv(/.*)?)" // lv Latvia
+ "|(ly(/.*)?)" // ly Libyan Arab Jamahiriya
+ "|(ma(/.*)?)" // ma Morocco
+ "|(mc(/.*)?)" // mc Monaco
+ "|(md(/.*)?)" // md Moldova, Republic of
+ "|(mg(/.*)?)" // mg Madagascar
+ "|(mh(/.*)?)" // mh Marshall Islands
+ "|(mil(/.*)?)" // mil Military (US Dept of Defense)
+ "|(mk(/.*)?)" // mk Macedonia, Former Yugoslav Republic
+ "|(ml(/.*)?)" // ml Mali
+ "|(mm(/.*)?)" // mm Myanmar
+ "|(mn(/.*)?)" // mn Mongolia
+ "|(mo(/.*)?)" // mo Macau
+ "|(mp(/.*)?)" // mp Northern Mariana Islands
+ "|(mq(/.*)?)" // mq Martinique
+ "|(mr(/.*)?)" // mr Mauritani
+ "|(ms(/.*)?)" // ms Montserrat
+ "|(mt(/.*)?)" // mt Malta
+ "|(mu(/.*)?)" // mu Mauritius
+ "|(museum(/.*)?)" // museum Museums
+ "|(mv(/.*)?)" // mv Maldives
+ "|(mw(/.*)?)" // mw Malawi
+ "|(mx(/.*)?)" // mx Mexico
+ "|(my(/.*)?)" // my Malaysia
+ "|(mz(/.*)?)" // mz Mozambique
+ "|(na(/.*)?)" // na Namibia
+ "|(name(/.*)?)" // name Individuals
+ "|(nc(/.*)?)" // nc New Caledonia
+ "|(ne(/.*)?)" // ne Niger
+ "|(net(/.*)?)" // net networks
+ "|(nf(/.*)?)" // nf Norfolk Island
+ "|(ng(/.*)?)" // ng Nigeria
+ "|(ni(/.*)?)" // ni Nicaragua
+ "|(nl(/.*)?)" // nl Netherlands
+ "|(no(/.*)?)" // no Norway
+ "|(np(/.*)?)" // np Nepal
+ "|(nr(/.*)?)" // nr Nauru
+ "|(nt(/.*)?)" // nt Neutral Zone
+ "|(nu(/.*)?)" // nu Niue
+ "|(nz(/.*)?)" // nz New Zealand
+ "|(om(/.*)?)" // om Oman
+ "|(org(/.*)?)" // org Organization (non-profit)
+ "|(pa(/.*)?)" // pa Panama
+ "|(pe(/.*)?)" // pe Peru
+ "|(pf(/.*)?)" // pf French Polynesia
+ "|(pg(/.*)?)" // pg Papua New Guinea
+ "|(ph(/.*)?)" // ph Philippines
+ "|(pk(/.*)?)" // pk Pakistan
+ "|(pl(/.*)?)" // pl Poland
+ "|(pm(/.*)?)" // pm St. Pierre and Miquelon
+ "|(pn(/.*)?)" // pn Pitcairn Island
+ "|(pr(/.*)?)" // pr Puerto Rico
+ "|(pro(/.*)?)" // pro Accountants, lawyers, and physicians
+ "|(ps(/.*)?)" // ps Palestinian Territories
+ "|(pt(/.*)?)" // pt Portugal
+ "|(pw(/.*)?)" // pw Palau
+ "|(py(/.*)?)" // py Paraguay
+ "|(qa(/.*)?)" // qa Qatar
+ "|(re(/.*)?)" // re Reunion Island
+ "|(ro(/.*)?)" // ro Romania
+ "|(ru(/.*)?)" // ru Russian Federation
+ "|(rw(/.*)?)" // rw Rwanda
+ "|(sa(/.*)?)" // sa Saudi Arabia
+ "|(sb(/.*)?)" // sb Solomon Islands
+ "|(sc(/.*)?)" // sc Seychelles
+ "|(sd(/.*)?)" // sd Sudan
+ "|(se(/.*)?)" // se Sweden
+ "|(sg(/.*)?)" // sg Singapore
+ "|(sh(/.*)?)" // sh St. Helena
+ "|(si(/.*)?)" // si Slovenia
+ "|(sj(/.*)?)" // sj Svalbard and Jan Mayen Islands
+ "|(sk(/.*)?)" // sk Slovak Republic
+ "|(sl(/.*)?)" // sl Sierra Leone
+ "|(sm(/.*)?)" // sm San Marino
+ "|(sn(/.*)?)" // sn Senegal
+ "|(so(/.*)?)" // so Somalia
+ "|(sr(/.*)?)" // sr Suriname
+ "|(sv(/.*)?)" // sv El Salvador
+ "|(st(/.*)?)" // st Sao Tome and Principe
+ "|(sy(/.*)?)" // sy Syrian Arab Republic
+ "|(sz(/.*)?)" // sz Swaziland
+ "|(tc(/.*)?)" // tc Turks and Caicos Islands
+ "|(td(/.*)?)" // td Chad
+ "|(tf(/.*)?)" // tf French Southern Territories
+ "|(tg(/.*)?)" // tg Togo
+ "|(th(/.*)?)" // th Thailand
+ "|(tj(/.*)?)" // tj Tajikistan
+ "|(tk(/.*)?)" // tk Tokelau
+ "|(tm(/.*)?)" // tm Turkmenistan
+ "|(tn(/.*)?)" // tn Tunisia
+ "|(to(/.*)?)" // to Tonga
+ "|(tp(/.*)?)" // tp East Timor
+ "|(tr(/.*)?)" // tr Turkey
+ "|(tt(/.*)?)" // tt Trinidad and Tobago
+ "|(tv(/.*)?)" // tv Tuvalu
+ "|(tw(/.*)?)" // tw Taiwan
+ "|(tz(/.*)?)" // tz Tanzania
+ "|(ua(/.*)?)" // ua Ukraine
+ "|(ug(/.*)?)" // ug Uganda
+ "|(uk(/.*)?)" // uk United Kingdom
+ "|(um(/.*)?)" // um US Minor Outlying Islands
+ "|(us(/.*)?)" // us United States
+ "|(uy(/.*)?)" // uy Uruguay
+ "|(uz(/.*)?)" // uz Uzbekistan
+ "|(va(/.*)?)" // va Holy See (City Vatican State)
+ "|(vc(/.*)?)" // vc Saint Vincent and the Grenadines
+ "|(ve(/.*)?)" // ve Venezuela
+ "|(vg(/.*)?)" // vg Virgin Islands (British)
+ "|(vi(/.*)?)" // vi Virgin Islands (USA)
+ "|(vn(/.*)?)" // vn Vietnam
+ "|(vu(/.*)?)" // vu Vanuatu
+ "|(wf(/.*)?)" // wf Wallis and Futuna Islands
+ "|(ws(/.*)?)" // ws Western Samoa
+ "|(ye(/.*)?)" // ye Yemen
+ "|(yt(/.*)?)" // yt Mayotte
+ "|(yu(/.*)?)" // yu Yugoslavia
+ "|(za(/.*)?)" // za South Africa
+ "|(zm(/.*)?)" // zm Zambia
+ "|(zw(/.*)?)" // zw Zimbabwe
);
/**
* Constructor.
*/
public ExtractorUniversal() {
}
@Override
protected boolean shouldExtract(CrawlURI uri) {
return true;
}
@Override
protected boolean innerExtract(CrawlURI curi) {
InputStream instream = null;
try {
instream = curi.getRecorder().getContentReplayInputStream();
int ch = instream.read();
StringBuffer lookat = new StringBuffer();
long counter = 0;
long maxdepth = getMaxSizeToParse();
if(maxdepth<=0) {
maxdepth = Long.MAX_VALUE;
}
long maxURLLength = UURI.MAX_URL_LENGTH;
boolean foundDot = false;
while(ch != -1 && ++counter <= maxdepth) {
if(lookat.length()>maxURLLength){
//Exceeded maximum length of a URL. Start fresh.
lookat = new StringBuffer();
foundDot = false;
}
else if(isURLableChar(ch)){
//Add to buffer.
if(ch == 46){
// Current character is a dot '.'
foundDot = true;
}
lookat.append((char)ch);
} else if(lookat.length() > 3 && foundDot) {
// It takes a bare mininum of 4 characters to form a URL
// Since we have at least that many let's try link
// extraction.
String newURL = lookat.toString();
if(looksLikeAnURL(newURL))
{
// Looks like we found something.
// Let's start with a little cleanup as we may have
// junk in front or at the end.
if(newURL.toLowerCase().indexOf("http") > 0){
// Got garbage in front of the protocol. Remove.
newURL = newURL.substring(newURL.toLowerCase().
indexOf("http"));
}
while(newURL.substring(newURL.length()-1).equals("."))
{
// URLs can't end with a dot. Strip it off.
newURL = newURL.substring(0,newURL.length()-1);
}
// And add the URL to speculative embeds.
numberOfLinksExtracted.incrementAndGet();
UURI dest = UURIFactory.getInstance(newURL);
LinkContext lc = LinkContext.SPECULATIVE_MISC;
Hop hop = Hop.SPECULATIVE;
addOutlink(curi, dest, lc, hop);
}
// Reset lookat for next string.
lookat = new StringBuffer();
foundDot = false;
} else if(lookat.length()>0) {
// Didn't get enough chars. Reset lookat for next string.
lookat = new StringBuffer();
foundDot = false;
}
ch = instream.read();
}
} catch(IOException e){
curi.getNonFatalFailures().add(e);
} finally {
IOUtils.closeQuietly(instream);
}
// Set flag to indicate that link extraction is completed.
return true;
}
/**
* This method takes a look at a string and determines if it could be a URL.
* To qualify the string must either begin with "http://" (https would also
* work) followed by something that looks like an IP address or contain
* within the string (possible at the end but not at the beginning) a TLD
* (Top Level Domain) preceded by a dot.
*
* @param lookat The string to examine in an effort to determine if it
* could be a URL
* @return True if the string matches the above criteria for a URL.
*/
private boolean looksLikeAnURL(String lookat) {
if(lookat.indexOf("http://")==0 || lookat.indexOf("https://")==0){
//Check if the rest of the string looks like an IP address.
//if so return true. Otherwise continue on.
Matcher ip = IP_ADDRESS.matcher(lookat);
boolean testVal = ip.matches();
if(testVal){
return true;
}
}
int dot = lookat.indexOf(".");
if(dot!=0){//An URL can't start with a .tld.
while(dot != -1 && dot < lookat.length()){
lookat = lookat.substring(dot+1);
if (isTLD(lookat.substring(0, lookat.length() <= 6?
lookat.length(): 6)))
{
return true;
}
dot = lookat.indexOf(".");
}
}
return false;
}
/**
* Checks if a string is equal to known Top Level Domain. The string may
* contain additional characters <i>after</i> the TLD but not before.
* @param potentialTLD The string (usually 2-6 chars) to check if it starts
* with a TLD.
* @return True if the given string starts with the name of a known TLD
*
* @see #TLDs
*/
private boolean isTLD(String potentialTLD) {
if(potentialTLD.length()<2){
return false;
}
potentialTLD = potentialTLD.toLowerCase();
Matcher uri = TLDs.matcher(potentialTLD);
boolean ret = uri.matches();
return ret;
}
/**
* Determines if a char (as represented by an int in the range of 0-255) is
* a character (in the Ansi character set) that can be present in a URL.
* This method takes a <b>strict</b> approach to what characters can be in
* a URL.
* <p>
* The following are considered to be 'URLable'<br>
* <ul>
* <li> <code># $ % & + , - . /</code> values 35-38,43-47
* <li> <code>[0-9]</code> values 48-57
* <li> <code>: ; = ? @</code> value 58-59,61,63-64
* <li> <code>[A-Z]</code> values 65-90
* <li> <code>_</code> value 95
* <li> <code>[a-z]</code> values 97-122
* <li> <code>~</code> value 126
* </ul>
* <p>
* To summerize, the following ranges are considered URLable:<br>
* 35-38,43-59,61,63-90,95,97-122,126
*
* @param ch The character (represented by an int) to test.
* @return True if it is a URLable character, false otherwise.
*/
private boolean isURLableChar(int ch) {
return (ch>=35 && ch<=38)
|| (ch>=43 && ch<=59)
|| (ch==61)
|| (ch>=63 && ch<=90)
|| (ch==95)
|| (ch>=97 && ch<=122)
|| (ch==126);
}
}