trunk/Search/Processor.cpp

/* ============================================================================
 * Douglas Thrift's Search Engine License
 *
 * Copyright (C) 2002-2004, Douglas Thrift. All Rights Reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * 3. The end-user documentation included with the redistribution, if any, must
 *    include the following acknowledgment:
 *
 *       "This product includes software developed by Douglas Thrift
 *       (http://computers.douglasthrift.net/searchengine/)."
 *
 *    Alternately, this acknowledgment may appear in the software itself, if
 *    and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Douglas Thrift" and "Douglas Thrift's Search Engine" must not
 *    be used to endorse or promote products derived from this software without
 *    specific prior written permission.  For written permission, please visit
 *    http://www.douglasthrift.net/contact.cgi for contact information.
 *
 * 5. Products derived from this software may not be called "Douglas Thrift's
 *    Search Engine", nor may "Douglas Thrift's Search Engine" appear in their
 *    name, without prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ============================================================================
 */
// Douglas Thrift's Search Engine Processor
//
// Douglas Thrift
//
// $Id$

#include "Processor.hpp"

Processor::Processor()
{
        page = new Page();
}

Processor::~Processor()
{
        delete page;
}

bool Processor::process(HttpHandler& http, URL& url)
{
        string title, description, text;
        vector<string> headings;

        if (http.contentType().find("text/html") == 0)
        {
                if (!process(http, url, title, description, text, headings)) return
                        false;

                entities(title, "&nbsp;", ' ');
                entities(title, "&lt;", '<');
                entities(title, "&gt;", '>');
                entities(title, "&quot;", '\"');
                entities(title, "&amp;", '&');
                entities(description, "&nbsp;", ' ');
                entities(description, "&lt;", '<');
                entities(description, "&gt;", '>');
                entities(description, "&quot;", '\"');
                entities(description, "&amp;", '&');
                entities(text, "&nbsp;", ' ');
                entities(text, "&lt;", '<');
                entities(text, "&gt;", '>');
                entities(text, "&quot;", '\"');
                entities(text, "&amp;", '&');

                for (int index = 0; index < headings.size(); index++)
                {
                        entities(headings[index], "&nbsp;", ' ');
                        entities(headings[index], "&lt;", '<');
                        entities(headings[index], "&gt;", '>');
                        entities(headings[index], "&quot;", '\"');
                        entities(headings[index], "&amp;", '&');
                }

                normalize(title);
                normalize(description);
                normalize(text);

                for (int index0 = 0; index0 < headings.size(); index0++)
                {
                        normalize(headings[index0]);
                }
        }
        else
        {
                string line;

                while (http.good())
                {
                        http.getline(line);

                        text += line + "\n";
                }

                normalize(text);
        }

        page->setSize(http.contentLength());
        page->setURL(url);
        page->setTitle(title);
        page->setDescription(description);
        page->setText(text);
        page->setHeadings(headings);

        return true;
}

void Processor::reset()
{
        links.clear();

        delete page;

        page = new Page();
}

bool Processor::process(HttpHandler& http, URL& url, string& title, string&
        description, string& text, vector<string>& headings)
{
        bool inHtml = false, inHead = false, inTitle = false, inBody = false,
                inHeading = false, inComment = false, follow = true, answer = true;
        string line, heading;

        while (http.good())
        {
                http.getline(line);

                unsigned begin = 0, startComment = 0;

                while (begin < line.length())
                {
                        unsigned open = line.find('<', begin);
                        unsigned close = line.find('>', begin);
                        string next;

                        while (close == string::npos && http.good())
                        {
                                http.getline(next);
                                line += '\n' + next;
                                close = line.find('>', begin);
                        }

                        // strangely this is necessary sometimes
                        if (open == string::npos) open = line.find('<', begin);

                        string between = line.substr(begin, open - begin);
                        string tag = getTag(line, open, close);
                        string lowerTag(tag.length(), ' ');

                        for (unsigned index = 0; index < tag.length(); index++)
                        {
                                lowerTag[index] = tolower(tag[index]);
                        }

                        if (inHtml && !inComment)
                        {
                                if (inHead && inTitle)
                                {
                                        title += between + "\n";
                                }

                                if (inBody)
                                {
                                        text += between + "\n";
                                }

                                if (inBody && inHeading)
                                {
                                        heading += between + "\n";
                                }

                                if (((lowerTag.find("meta ") == 0) || (lowerTag.find("meta\n")
                                        == 0) || (lowerTag.find("meta   ") == 0)) && inHead)
                                {
                                        if (lowerTag.find("name=robots") != string::npos ||
                                                lowerTag.find("name=\"robots\"") != string::npos)
                                        {
                                                unsigned start = lowerTag.find("content=\"") + 9;
                                                unsigned finish = lowerTag.find('\"', start);

                                                string robots = lowerTag.substr(start, finish - start);

                                                if ((robots.find("noindex") != string::npos &&
                                                        robots.find("nofollow") != string::npos) ||
                                                        robots.find("none") != string::npos)
                                                {
                                                        answer = false;
                                                        follow = false;
                                                        links.clear();

                                                        return answer;
                                                }
                                                else if (robots.find("noindex") != string::npos)
                                                {
                                                        answer = false;
                                                }
                                                else if (robots.find("nofollow") != string::npos)
                                                {
                                                        follow = false;
                                                        links.clear();
                                                }
                                        }
                                        else if (lowerTag.find("name=description") != string::npos
                                                || lowerTag.find("name=\"description\"") !=
                                                string::npos)
                                        {
                                                unsigned start = lowerTag.find("content=\"") + 9;
                                                unsigned finish = lowerTag.find('\"', start);

                                                description = tag.substr(start, finish - start);
                                        }
                                }

                                if (((lowerTag.find("a ") == 0) || (lowerTag.find("a\n") == 0)
                                        || (lowerTag.find("a    ") == 0)) && inBody && follow)
                                {
                                        if (lowerTag.find("href=\"") != string::npos)
                                        {
                                                unsigned start = lowerTag.find("href=\"") + 6;
                                                unsigned finish = lowerTag.find('\"', start);

                                                string link = getLink(tag.substr(start, finish -
                                                        start), url);

                                                if (link != "") links.insert(link);
                                        }
                                        else if (lowerTag.find("href=") != string::npos)
                                        {
                                                unsigned start = lowerTag.find("href=") + 5;
                                                unsigned finish = lowerTag.find(' ', start);

                                                if (finish < close)
                                                {
                                                        string link = getLink(tag.substr(start, finish -
                                                                start), url);

                                                        if (link != "") links.insert(link);
                                                }
                                                else
                                                {
                                                        string link = getLink(tag.substr(start, close -
                                                                start), url);

                                                        if (link != "") links.insert(link);
                                                }
                                        }
                                }

                                if ((lowerTag.find("img ") == 0) || (lowerTag.find("img\n") ==
                                        0) || (lowerTag.find("img       ")) && inBody)
                                {
                                        if (lowerTag.find("alt=\"") != string::npos)
                                        {
                                                unsigned start = lowerTag.find("alt=\"") + 5;
                                                unsigned finish = lowerTag.find('\"', start);

                                                text += tag.substr(start, finish - start) + ' ';
                                                if (inHeading) heading += tag.substr(start, finish -
                                                        start) + ' ';
                                        }
                                        else if (lowerTag.find("alt=") != string::npos)
                                        {
                                                unsigned start = lowerTag.find("alt=") + 4;
                                                unsigned finish = lowerTag.find(' ', start);

                                                if (finish < close)
                                                {
                                                        text += tag.substr(start, finish - start) + ' ';
                                                        if (inHeading) heading += tag.substr(start, finish
                                                                - start) + ' ';
                                                }
                                                else
                                                {
                                                        text += tag.substr(start, close - start) + ' ';
                                                        if (inHeading) heading += tag.substr(start, close -
                                                                start) + ' ';
                                                }
                                        }
                                }
                        }

                        if (lowerTag.find("html") == 0) inHtml = true;
                        if (lowerTag.find("/html") == 0) inHtml = false;
                        if (lowerTag.find("head") == 0) inHead = true;
                        if (lowerTag.find("/head") == 0) inHead = false;
                        if (lowerTag.find("title") == 0) inTitle = true;
                        if (lowerTag.find("/title") == 0) inTitle = false;
                        if (lowerTag.find("body") == 0 || lowerTag.find("noframes") == 0)
                                inBody = true;
                        if (lowerTag.find("/body") == 0 || lowerTag.find("/noframes") == 0)
                                inBody = false;

                        if (lowerTag.find("h1") == 0 || lowerTag.find("h2") == 0 ||
                                lowerTag.find("h3") == 0 || lowerTag.find("h4") == 0 ||
                                lowerTag.find("h5") == 0 || lowerTag.find("h6") == 0)
                        {
                                heading = "";
                                inHeading = true;
                        }

                        if (lowerTag.find("/h1") == 0 || lowerTag.find("/h2") == 0 ||
                                lowerTag.find("/h3") == 0 || lowerTag.find("/h4") == 0 ||
                                lowerTag.find("/h5") == 0 || lowerTag.find("/h6") == 0)
                        {
                                if (heading != "") headings.push_back(heading);

                                inHeading = false;
                        }

                        if (lowerTag.find("!--") == 0)
                        {
                                startComment = open;
                                inComment = true;
                        }

                        if (line.find("-->", begin) >= startComment && line.find("-->",
                                begin) != string::npos)
                        {
                                close = line.find("-->", begin) + 3;
                                inComment = false;
                        }

                        if (close == string::npos)
                        {
                                begin = close;
                        }
                        else
                        {
                                begin = close + 1;
                        }
                }
        }

        return answer;
}

string Processor::getTag(const string& line, unsigned open, unsigned close)
{
        string tag = line.substr(open + 1, close - open - 1);

        return tag;
}
Revision:	334
Committed:	2004-04-05T16:37:41-07:00 (21 years, 2 months ago) by Douglas Thrift
File size:	10138 byte(s)
Log Message:	Ah, I just love Subversion!
#	Content
1	/* ============================================================================
2	* Douglas Thrift's Search Engine License
3	*
4	* Copyright (C) 2002-2004, Douglas Thrift. All Rights Reserved.
5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions are met:
7	*
8	* 1. Redistributions of source code must retain the above copyright notice,
9	* this list of conditions and the following disclaimer.
10	*
11	* 2. Redistributions in binary form must reproduce the above copyright notice,
12	* this list of conditions and the following disclaimer in the documentation
13	* and/or other materials provided with the distribution.
14	*
15	* 3. The end-user documentation included with the redistribution, if any, must
16	* include the following acknowledgment:
17	*
18	* "This product includes software developed by Douglas Thrift
19	* (http://computers.douglasthrift.net/searchengine/)."
20	*
21	* Alternately, this acknowledgment may appear in the software itself, if
22	* and wherever such third-party acknowledgments normally appear.
23	*
24	* 4. The names "Douglas Thrift" and "Douglas Thrift's Search Engine" must not
25	* be used to endorse or promote products derived from this software without
26	* specific prior written permission. For written permission, please visit
27	* http://www.douglasthrift.net/contact.cgi for contact information.
28	*
29	* 5. Products derived from this software may not be called "Douglas Thrift's
30	* Search Engine", nor may "Douglas Thrift's Search Engine" appear in their
31	* name, without prior written permission.
32	*
33	* THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
34	* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
35	* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
36	* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
37	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
38	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
39	* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
40	* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
41	* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
42	* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43	* ============================================================================
44	*/
45	// Douglas Thrift's Search Engine Processor
46	//
47	// Douglas Thrift
48	//
49	// $Id$
50
51	#include "Processor.hpp"
52
53	Processor::Processor()
54	{
55	page = new Page();
56	}
57
58	Processor::~Processor()
59	{
60	delete page;
61	}
62
63	bool Processor::process(HttpHandler& http, URL& url)
64	{
65	string title, description, text;
66	vector<string> headings;
67
68	if (http.contentType().find("text/html") == 0)
69	{
70	if (!process(http, url, title, description, text, headings)) return
71	false;
72
73	entities(title, " ", ' ');
74	entities(title, "<", '<');
75	entities(title, ">", '>');
76	entities(title, """, '\"');
77	entities(title, "&", '&');
78	entities(description, " ", ' ');
79	entities(description, "<", '<');
80	entities(description, ">", '>');
81	entities(description, """, '\"');
82	entities(description, "&", '&');
83	entities(text, " ", ' ');
84	entities(text, "<", '<');
85	entities(text, ">", '>');
86	entities(text, """, '\"');
87	entities(text, "&", '&');
88
89	for (int index = 0; index < headings.size(); index++)
90	{
91	entities(headings[index], " ", ' ');
92	entities(headings[index], "<", '<');
93	entities(headings[index], ">", '>');
94	entities(headings[index], """, '\"');
95	entities(headings[index], "&", '&');
96	}
97
98	normalize(title);
99	normalize(description);
100	normalize(text);
101
102	for (int index0 = 0; index0 < headings.size(); index0++)
103	{
104	normalize(headings[index0]);
105	}
106	}
107	else
108	{
109	string line;
110
111	while (http.good())
112	{
113	http.getline(line);
114
115	text += line + "\n";
116	}
117
118	normalize(text);
119	}
120
121	page->setSize(http.contentLength());
122	page->setURL(url);
123	page->setTitle(title);
124	page->setDescription(description);
125	page->setText(text);
126	page->setHeadings(headings);
127
128	return true;
129	}
130
131	void Processor::reset()
132	{
133	links.clear();
134
135	delete page;
136
137	page = new Page();
138	}
139
140	bool Processor::process(HttpHandler& http, URL& url, string& title, string&
141	description, string& text, vector<string>& headings)
142	{
143	bool inHtml = false, inHead = false, inTitle = false, inBody = false,
144	inHeading = false, inComment = false, follow = true, answer = true;
145	string line, heading;
146
147	while (http.good())
148	{
149	http.getline(line);
150
151	unsigned begin = 0, startComment = 0;
152
153	while (begin < line.length())
154	{
155	unsigned open = line.find('<', begin);
156	unsigned close = line.find('>', begin);
157	string next;
158
159	while (close == string::npos && http.good())
160	{
161	http.getline(next);
162	line += '\n' + next;
163	close = line.find('>', begin);
164	}
165
166	// strangely this is necessary sometimes
167	if (open == string::npos) open = line.find('<', begin);
168
169	string between = line.substr(begin, open - begin);
170	string tag = getTag(line, open, close);
171	string lowerTag(tag.length(), ' ');
172
173	for (unsigned index = 0; index < tag.length(); index++)
174	{
175	lowerTag[index] = tolower(tag[index]);
176	}
177
178	if (inHtml && !inComment)
179	{
180	if (inHead && inTitle)
181	{
182	title += between + "\n";
183	}
184
185	if (inBody)
186	{
187	text += between + "\n";
188	}
189
190	if (inBody && inHeading)
191	{
192	heading += between + "\n";
193	}
194
195	if (((lowerTag.find("meta ") == 0) \|\| (lowerTag.find("meta\n")
196	== 0) \|\| (lowerTag.find("meta ") == 0)) && inHead)
197	{
198	if (lowerTag.find("name=robots") != string::npos \|\|
199	lowerTag.find("name=\"robots\"") != string::npos)
200	{
201	unsigned start = lowerTag.find("content=\"") + 9;
202	unsigned finish = lowerTag.find('\"', start);
203
204	string robots = lowerTag.substr(start, finish - start);
205
206	if ((robots.find("noindex") != string::npos &&
207	robots.find("nofollow") != string::npos) \|\|
208	robots.find("none") != string::npos)
209	{
210	answer = false;
211	follow = false;
212	links.clear();
213
214	return answer;
215	}
216	else if (robots.find("noindex") != string::npos)
217	{
218	answer = false;
219	}
220	else if (robots.find("nofollow") != string::npos)
221	{
222	follow = false;
223	links.clear();
224	}
225	}
226	else if (lowerTag.find("name=description") != string::npos
227	\|\| lowerTag.find("name=\"description\"") !=
228	string::npos)
229	{
230	unsigned start = lowerTag.find("content=\"") + 9;
231	unsigned finish = lowerTag.find('\"', start);
232
233	description = tag.substr(start, finish - start);
234	}
235	}
236
237	if (((lowerTag.find("a ") == 0) \|\| (lowerTag.find("a\n") == 0)
238	\|\| (lowerTag.find("a ") == 0)) && inBody && follow)
239	{
240	if (lowerTag.find("href=\"") != string::npos)
241	{
242	unsigned start = lowerTag.find("href=\"") + 6;
243	unsigned finish = lowerTag.find('\"', start);
244
245	string link = getLink(tag.substr(start, finish -
246	start), url);
247
248	if (link != "") links.insert(link);
249	}
250	else if (lowerTag.find("href=") != string::npos)
251	{
252	unsigned start = lowerTag.find("href=") + 5;
253	unsigned finish = lowerTag.find(' ', start);
254
255	if (finish < close)
256	{
257	string link = getLink(tag.substr(start, finish -
258	start), url);
259
260	if (link != "") links.insert(link);
261	}
262	else
263	{
264	string link = getLink(tag.substr(start, close -
265	start), url);
266
267	if (link != "") links.insert(link);
268	}
269	}
270	}
271
272	if ((lowerTag.find("img ") == 0) \|\| (lowerTag.find("img\n") ==
273	0) \|\| (lowerTag.find("img ")) && inBody)
274	{
275	if (lowerTag.find("alt=\"") != string::npos)
276	{
277	unsigned start = lowerTag.find("alt=\"") + 5;
278	unsigned finish = lowerTag.find('\"', start);
279
280	text += tag.substr(start, finish - start) + ' ';
281	if (inHeading) heading += tag.substr(start, finish -
282	start) + ' ';
283	}
284	else if (lowerTag.find("alt=") != string::npos)
285	{
286	unsigned start = lowerTag.find("alt=") + 4;
287	unsigned finish = lowerTag.find(' ', start);
288
289	if (finish < close)
290	{
291	text += tag.substr(start, finish - start) + ' ';
292	if (inHeading) heading += tag.substr(start, finish
293	- start) + ' ';
294	}
295	else
296	{
297	text += tag.substr(start, close - start) + ' ';
298	if (inHeading) heading += tag.substr(start, close -
299	start) + ' ';
300	}
301	}
302	}
303	}
304
305	if (lowerTag.find("html") == 0) inHtml = true;
306	if (lowerTag.find("/html") == 0) inHtml = false;
307	if (lowerTag.find("head") == 0) inHead = true;
308	if (lowerTag.find("/head") == 0) inHead = false;
309	if (lowerTag.find("title") == 0) inTitle = true;
310	if (lowerTag.find("/title") == 0) inTitle = false;
311	if (lowerTag.find("body") == 0 \|\| lowerTag.find("noframes") == 0)
312	inBody = true;
313	if (lowerTag.find("/body") == 0 \|\| lowerTag.find("/noframes") == 0)
314	inBody = false;
315
316	if (lowerTag.find("h1") == 0 \|\| lowerTag.find("h2") == 0 \|\|
317	lowerTag.find("h3") == 0 \|\| lowerTag.find("h4") == 0 \|\|
318	lowerTag.find("h5") == 0 \|\| lowerTag.find("h6") == 0)
319	{
320	heading = "";
321	inHeading = true;
322	}
323
324	if (lowerTag.find("/h1") == 0 \|\| lowerTag.find("/h2") == 0 \|\|
325	lowerTag.find("/h3") == 0 \|\| lowerTag.find("/h4") == 0 \|\|
326	lowerTag.find("/h5") == 0 \|\| lowerTag.find("/h6") == 0)
327	{
328	if (heading != "") headings.push_back(heading);
329
330	inHeading = false;
331	}
332
333	if (lowerTag.find("!--") == 0)
334	{
335	startComment = open;
336	inComment = true;
337	}
338
339	if (line.find("-->", begin) >= startComment && line.find("-->",
340	begin) != string::npos)
341	{
342	close = line.find("-->", begin) + 3;
343	inComment = false;
344	}
345
346	if (close == string::npos)
347	{
348	begin = close;
349	}
350	else
351	{
352	begin = close + 1;
353	}
354	}
355	}
356
357	return answer;
358	}
359
360	string Processor::getTag(const string& line, unsigned open, unsigned close)
361	{
362	string tag = line.substr(open + 1, close - open - 1);
363
364	return tag;
365	}