/* Checks the accuracy of the HITS computation */
void
test_hits(CuTest *tc) {
/* Compute the HITS score of the following graph
* +-->2---+
* | | |
* | v v
* 1-->5<--3
* ^ ^ |
* | | |
* +---4<--+
*
* The link matrix L[i,j], where L[i,j] = 1 means 'i' links to 'j' is:
*
* +- -+
* | 0 1 0 0 1 |
* | 0 0 1 0 1 |
* L = | 0 0 0 1 1 |
* | 1 0 0 0 1 |
* | 0 0 0 0 0 |
* +- -+
*/
char test_dir[] = "test-pagedb-XXXXXX";
mkdtemp(test_dir);
PageDB *db;
int ret = page_db_new(&db, test_dir);
CuAssert(tc,
db!=0? db->error->message: "NULL",
ret == 0);
db->persist = 0;
char *urls[5] = {"1", "2", "3", "4", "5" };
LinkInfo links_1[] = {{"2", 0.1}, {"5", 0.1}};
LinkInfo links_2[] = {{"3", 0.1}, {"5", 0.1}};
LinkInfo links_3[] = {{"4", 0.1}, {"5", 0.1}};
LinkInfo links_4[] = {{"1", 0.1}, {"5", 0.1}};
LinkInfo *links[5] = {
links_1, links_2, links_3, links_4, 0
};
int n_links[5] = {2, 2, 2, 2, 0};
for (int i=0; i<5; ++i) {
CrawledPage *cp = crawled_page_new(urls[i]);
for (int j=0; j<n_links[i]; ++j)
crawled_page_add_link(cp, links[i][j].url, links[i][j].score);
cp->score = i/5.0;
crawled_page_set_hash64(cp, i);
PageInfoList *pil;
CuAssert(tc,
db->error->message,
page_db_add(db, cp, &pil) == 0);
page_info_list_delete(pil);
crawled_page_delete(cp);
}
PageDBLinkStream *st;
CuAssert(tc,
db->error->message,
page_db_link_stream_new(&st, db) == 0);
st->only_diff_domain = 0;
Hits *hits;
ret = hits_new(&hits, test_dir, 5);
CuAssert(tc,
hits!=0? hits->error->message: "NULL",
ret == 0);
hits->precision = 1e-8;
CuAssert(tc,
hits->error->message,
hits_compute(hits,
st,
page_db_link_stream_next,
page_db_link_stream_reset) == 0);
page_db_link_stream_delete(st);
uint64_t idx;
float *h_score;
float *a_score;
float h_scores[5] = {0.250, 0.250, 0.250, 0.250, 0.000};
float a_scores[5] = {0.125, 0.125, 0.125, 0.125, 0.500};
for (int i=0; i<5; ++i) {
CuAssert(tc,
db->error->message,
page_db_get_idx(db, page_db_hash(urls[i]), &idx) == 0);
CuAssertPtrNotNull(tc,
h_score = mmap_array_idx(hits->h1, idx));
CuAssertPtrNotNull(tc,
a_score = mmap_array_idx(hits->a1, idx));
CuAssertDblEquals(tc, h_scores[i], *h_score, 1e-6);
CuAssertDblEquals(tc, a_scores[i], *a_score, 1e-6);
}
CuAssert(tc,
hits->error->message,
hits_delete(hits) == 0);
page_db_delete(db);
}
FreqSchedulerError
freq_scheduler_cursor_write(FreqScheduler *sch,
MDB_cursor *cursor,
uint64_t hash,
float freq) {
if (freq <= 0)
return 0;
ScheduleKey sk = {
.score = 0,
.hash = hash
};
MDB_val key = {
.mv_size = sizeof(sk),
.mv_data = &sk,
};
MDB_val val = {
.mv_size = sizeof(float),
.mv_data = &freq,
};
int mdb_rc;
if ((mdb_rc = mdb_cursor_put(cursor, &key, &val, 0)) != 0) {
freq_scheduler_set_error(sch, freq_scheduler_error_internal, __func__);
freq_scheduler_add_error(sch, "adding page to schedule");
freq_scheduler_add_error(sch, mdb_strerror(mdb_rc));
}
return sch->error->code;
}
FreqSchedulerError
freq_scheduler_load_simple(FreqScheduler *sch,
float freq_default,
float freq_scale) {
char *error1 = 0;
char *error2 = 0;
MDB_cursor *cursor = 0;
HashInfoStream *st;
if (hashinfo_stream_new(&st, sch->page_db) != 0) {
error1 = "creating stream";
error2 = st? sch->page_db->error->message: "NULL";
goto on_error;
}
if (freq_scheduler_cursor_open(sch, &cursor) != 0)
goto on_error;
StreamState ss;
uint64_t hash;
PageInfo *pi;
while ((ss = hashinfo_stream_next(st, &hash, &pi)) == stream_state_next) {
if ((pi->n_crawls > 0) &&
((sch->max_n_crawls == 0) || (pi->n_crawls < sch->max_n_crawls)) &&
!page_info_is_seed(pi)){
float freq = freq_default;
if (freq_scale > 0) {
float rate = page_info_rate(pi);
if (rate > 0) {
freq = freq_scale * rate;
}
}
if (freq_scheduler_cursor_write(sch, cursor, hash, freq) != 0)
goto on_error;
}
page_info_delete(pi);
}
if (ss != stream_state_end) {
error1 = "incorrect stream state";
error2 = 0;
hashinfo_stream_delete(st);
goto on_error;
}
hashinfo_stream_delete(st);
if (freq_scheduler_cursor_commit(sch, cursor) != 0)
goto on_error;
return sch->error->code;
on_error:
freq_scheduler_cursor_abort(sch, cursor);
freq_scheduler_set_error(sch, freq_scheduler_error_internal, __func__);
freq_scheduler_add_error(sch, error1);
freq_scheduler_add_error(sch, error2);
return sch->error->code;
}
FreqSchedulerError
freq_scheduler_load_mmap(FreqScheduler *sch, MMapArray *freqs) {
char *error1 = 0;
char *error2 = 0;
MDB_cursor *cursor = 0;
if (txn_manager_expand(
sch->txn_manager,
2*freqs->n_elements*freqs->element_size) != 0) {
error1 = "resizing database";
error2 = sch->txn_manager->error->message;
goto on_error;
}
if (freq_scheduler_cursor_open(sch, &cursor) != 0)
goto on_error;
for (size_t i=0; i<freqs->n_elements; ++i) {
PageFreq *f = mmap_array_idx(freqs, i);
ScheduleKey sk = {
.score = 1.0/f->freq,
.hash = f->hash
};
MDB_val key = {
.mv_size = sizeof(sk),
.mv_data = &sk,
};
MDB_val val = {
.mv_size = sizeof(float),
.mv_data = &f->freq,
};
int mdb_rc;
if ((mdb_rc = mdb_cursor_put(cursor, &key, &val, 0)) != 0) {
error1 = "adding page to schedule";
error2 = mdb_strerror(mdb_rc);
goto on_error;
}
}
if (freq_scheduler_cursor_commit(sch, cursor) != 0)
goto on_error;
return sch->error->code;
on_error:
freq_scheduler_cursor_abort(sch, cursor);
freq_scheduler_set_error(sch, freq_scheduler_error_internal, __func__);
freq_scheduler_add_error(sch, error1);
freq_scheduler_add_error(sch, error2);
return sch->error->code;
}
FreqSchedulerError
freq_scheduler_request(FreqScheduler *sch,
size_t max_requests,
PageRequest **request) {
char *error1 = 0;
char *error2 = 0;
MDB_cursor *cursor = 0;
if (freq_scheduler_cursor_open(sch, &cursor) != 0)
goto on_error;
PageRequest *req = *request = page_request_new(max_requests);
if (!req) {
error1 = "allocating memory";
goto on_error;
}
int interrupt_requests = 0;
while ((req->n_urls < max_requests) && !interrupt_requests) {
MDB_val key;
MDB_val val;
ScheduleKey sk;
float freq;
int mdb_rc;
int crawl = 0;
switch (mdb_rc = mdb_cursor_get(cursor, &key, &val, MDB_FIRST)) {
case 0:
// copy data before deleting cursor
sk = *(ScheduleKey*)key.mv_data;
freq = *(float*)val.mv_data;
PageInfo *pi = 0;
if (page_db_get_info(sch->page_db, sk.hash, &pi) != 0) {
error1 = "retrieving PageInfo from PageDB";
error2 = sch->page_db->error->message;
goto on_error;
}
if (pi) {
if (sch->margin >= 0) {
double elapsed = difftime(time(0), 0) - pi->last_crawl;
if (elapsed < 1.0/(freq*(1.0 + sch->margin)))
interrupt_requests = 1;
}
crawl = (sch->max_n_crawls == 0) || (pi->n_crawls < sch->max_n_crawls);
}
if (!interrupt_requests) {
if ((mdb_rc = mdb_cursor_del(cursor, 0)) != 0) {
error1 = "deleting head of schedule";
error2 = mdb_strerror(mdb_rc);
goto on_error;
}
if (crawl) {
if (page_request_add_url(req, pi->url) != 0) {
error1 = "adding url to request";
goto on_error;
}
sk.score += 1.0/freq;
val.mv_data = &freq;
key.mv_data = &sk;
if ((mdb_rc = mdb_cursor_put(cursor, &key, &val, 0)) != 0) {
error1 = "moving element inside schedule";
error2 = mdb_strerror(mdb_rc);
goto on_error;
}
}
}
page_info_delete(pi);
break;
case MDB_NOTFOUND: // no more pages left
interrupt_requests = 1;
break;
default:
error1 = "getting head of schedule";
error2 = mdb_strerror(mdb_rc);
goto on_error;
}
}
if (freq_scheduler_cursor_commit(sch, cursor) != 0)
goto on_error;
return sch->error->code;
on_error:
freq_scheduler_cursor_abort(sch, cursor);
freq_scheduler_set_error(sch, freq_scheduler_error_internal, __func__);
freq_scheduler_add_error(sch, error1);
freq_scheduler_add_error(sch, error2);
return sch->error->code;
}
FreqSchedulerError
freq_scheduler_add(FreqScheduler *sch, const CrawledPage *page) {
if (page_db_add(sch->page_db, page, 0) != 0) {
freq_scheduler_set_error(sch, freq_scheduler_error_internal, __func__);
freq_scheduler_add_error(sch, "adding crawled page");
freq_scheduler_add_error(sch, sch->page_db->error->message);
}
return sch->error->code;
}
void
freq_scheduler_delete(FreqScheduler *sch) {
mdb_env_close(sch->txn_manager->env);
(void)txn_manager_delete(sch->txn_manager);
if (!sch->persist) {
char *data = build_path(sch->path, "data.mdb");
char *lock = build_path(sch->path, "lock.mdb");
remove(data);
remove(lock);
free(data);
free(lock);
remove(sch->path);
}
free(sch->path);
error_delete(sch->error);
free(sch);
}
FreqSchedulerError
freq_scheduler_dump(FreqScheduler *sch, FILE *output) {
MDB_cursor *cursor;
if (freq_scheduler_cursor_open(sch, &cursor) != 0)
return sch->error->code;
int end = 0;
MDB_cursor_op cursor_op = MDB_FIRST;
do {
int mdb_rc;
MDB_val key;
MDB_val val;
ScheduleKey *key_data;
float *val_data;
switch (mdb_rc = mdb_cursor_get(cursor, &key, &val, cursor_op)) {
case 0:
key_data = (ScheduleKey*)key.mv_data;
val_data = (float*)val.mv_data;
fprintf(output, "%.2e %016"PRIx64" %.2e\n",
key_data->score, key_data->hash, *val_data);
break;
case MDB_NOTFOUND:
end = 1;
break;
default:
freq_scheduler_set_error(sch, freq_scheduler_error_internal, __func__);
freq_scheduler_add_error(sch, "iterating over database");
freq_scheduler_add_error(sch, mdb_strerror(mdb_rc));
end = 1;
break;
}
cursor_op = MDB_NEXT;
} while (!end);
freq_scheduler_cursor_abort(sch, cursor);
return sch->error->code;
}
/* Tests the loading/dumping of PageInfo from and into LMDB values */
void
test_page_info_serialization(CuTest *tc) {
printf("%s\n", __func__);
MDB_val val;
PageInfo pi1 = {
.url = "test_url_123",
.first_crawl = 123,
.last_crawl = 456,
.n_changes = 100,
.n_crawls = 20,
.score = 0.7,
.content_hash_length = 8,
.content_hash = "1234567"
};
CuAssertTrue(tc, page_info_dump(&pi1, &val) == 0);
CuAssertDblEquals(tc, 0.7, page_info_dump_get_score(&val), 1e-6);
PageInfo *pi2 = page_info_load(&val);
CuAssertPtrNotNull(tc, pi2);
free(val.mv_data);
CuAssertStrEquals(tc, pi1.url, pi2->url);
CuAssertTrue(tc, pi1.first_crawl == pi2->first_crawl);
CuAssertTrue(tc, pi1.last_crawl == pi2->last_crawl);
CuAssertTrue(tc, pi1.n_changes == pi2->n_changes);
CuAssertTrue(tc, pi1.n_crawls == pi2->n_crawls);
CuAssertTrue(tc, pi1.score == pi2->score);
CuAssertTrue(tc, pi1.content_hash_length == pi2->content_hash_length);
CuAssertStrEquals(tc, pi1.content_hash, pi2->content_hash);
page_info_delete(pi2);
}
/* Tests all the database operations on a very simple crawl of just two pages */
void
test_page_db_simple(CuTest *tc) {
printf("%s\n", __func__);
char test_dir[] = "test-pagedb-XXXXXX";
mkdtemp(test_dir);
PageDB *db;
int ret = page_db_new(&db, test_dir);
CuAssert(tc,
db!=0? db->error->message: "NULL",
ret == 0);
db->persist = 0;
CrawledPage *cp1 = crawled_page_new("www.yahoo.com");
crawled_page_add_link(cp1, "a", 0.1);
crawled_page_add_link(cp1, "b", 0.2);
crawled_page_add_link(cp1, "www.google.com", 0.3);
crawled_page_set_hash64(cp1, 1000);
cp1->score = 0.5;
CrawledPage *cp2 = crawled_page_new("www.bing.com");
crawled_page_add_link(cp2, "x", 1.1);
crawled_page_add_link(cp2, "y", 1.2);
crawled_page_set_hash64(cp2, 2000);
cp2->score = 0.2;
PageInfoList *pil;
CuAssert(tc,
db->error->message,
page_db_add(db, cp1, &pil) == 0);
page_info_list_delete(pil);
CuAssert(tc,
db->error->message,
page_db_add(db, cp2, &pil) == 0);
page_info_list_delete(pil);
crawled_page_set_hash64(cp2, 3000);
CuAssert(tc,
db->error->message,
page_db_add(db, cp2, &pil) == 0);
page_info_list_delete(pil);
MMapArray *scores = 0;
CuAssert(tc,
db->error->message,
page_db_get_scores(db, &scores) == 0);
size_t idx;
CuAssert(tc,
db->error->message,
page_db_get_idx(db, page_db_hash("www.yahoo.com"), &idx) == 0);
CuAssertDblEquals(
tc,
0.5,
*(float*)mmap_array_idx(scores, idx),
1e-6);
CuAssert(tc,
db->error->message,
page_db_get_idx(db, page_db_hash("x"), &idx) == 0);
CuAssertDblEquals(
tc,
1.1,
*(float*)mmap_array_idx(scores, idx),
1e-6);
CHECK_DELETE(tc, scores->error->message, mmap_array_delete(scores));
crawled_page_delete(cp1);
crawled_page_delete(cp2);
char pi_out[1000];
char *print_pages[] = {"www.yahoo.com", "www.google.com", "www.bing.com"};
for (size_t i=0; i<3; ++i) {
PageInfo *pi;
CuAssert(tc,
db->error->message,
page_db_get_info(db, page_db_hash(print_pages[i]), &pi) == 0);
CuAssertPtrNotNull(tc, pi);
switch(i) {
case 0:
CuAssertIntEquals(tc, 1, pi->n_crawls);
CuAssertIntEquals(tc, 0, pi->n_changes);
break;
case 1:
CuAssertIntEquals(tc, 0, pi->n_crawls);
break;
case 2:
CuAssertIntEquals(tc, 2, pi->n_crawls);
CuAssertIntEquals(tc, 1, pi->n_changes);
break;
}
page_info_print(pi, pi_out);
page_info_delete(pi);
/* show on screen the page info:
*
* Mon Apr 6 15:34:50 2015|Mon Apr 6 15:34:50 2015|1.00e+00|0.00e+00|www.yahoo.com
* Thu Jan 1 01:00:00 1970|Thu Jan 1 01:00:00 1970|0.00e+00|0.00e+00|www.google.com
* Mon Apr 6 15:34:50 2015|Mon Apr 6 15:34:50 2015|2.00e+00|1.00e+00|www.bing.com
*/
#if 0
printf("%s\n", pi_out);
#endif
}
PageDBLinkStream *es;
CuAssert(tc,
db->error->message,
page_db_link_stream_new(&es, db) == 0);
es->only_diff_domain = 0;
if (es->state == stream_state_init) {
Link link;
int i=0;
while (page_db_link_stream_next(es, &link) == stream_state_next) {
switch(i++) {
case 0:
CuAssertIntEquals(tc, 0, link.from);
CuAssertIntEquals(tc, 1, link.to);
break;
case 1:
CuAssertIntEquals(tc, 0, link.from);
CuAssertIntEquals(tc, 2, link.to);
break;
case 2:
CuAssertIntEquals(tc, 0, link.from);
CuAssertIntEquals(tc, 3, link.to);
break;
case 3:
CuAssertIntEquals(tc, 4, link.from);
CuAssertIntEquals(tc, 5, link.to);
break;
case 4:
CuAssertIntEquals(tc, 4, link.from);
CuAssertIntEquals(tc, 6, link.to);
break;
default:
CuFail(tc, "too many links");
break;
}
}
CuAssertTrue(tc, es->state != stream_state_error);
}
page_db_link_stream_delete(es);
page_db_delete(db);
}
/* Checks the accuracy of the PageRank computation */
void
test_page_rank(CuTest *tc) {
printf("%s\n", __func__);
/* Compute the PageRank score of the following graph
* +-->2---+
* | | |
* | v v
* 1-->5<--3
* ^ ^ |
* | | |
* +---4<--+
*
* The link matrix L[i,j], where L[i,j] = 1 means 'i' links to 'j' is:
*
* +- -+
* | 0 1 0 0 1 |
* | 0 0 1 0 1 |
* L = | 0 0 0 1 1 |
* | 1 0 0 0 1 |
* | 0 0 0 0 0 |
* +- -+
*
* Since page "5" has no outbound links, it is assumed it links to every other page:
*
* +- -+
* | 0 1 0 0 1 |
* | 0 0 1 0 1 |
* L = | 0 0 0 1 1 |
* | 1 0 0 0 1 |
* | 1 1 1 1 1 |
* +- -+
*
* The out degree is:
*
* deg = {2, 2, 2, 2, 5}
*
* Dividing each row with the out degree and transposing we get the matrix:
*
* M[i, j] = L[j, i]/deg[j]
*
* we get:
*
* +- -+
* | 0 0 0 0.5 0.2 |
* | 0.5 0 0 0 0.2 |
* M = | 0 0.5 0 0 0.2 |
* | 0 0 0.5 0 0.2 |
* | 0.5 0.5 0.5 0.5 0.2 |
* +- -+
*
* If 'd' is the damping then the PageRank 'PR' is:
*
* 1 - d
* PR = ----- + (d * M)*PR
* N
*
* For d=0.85 the numerical solution is:
*
* PR(1) = PR(2) = PR(3) = PR(4) = 0.15936255
* PR(5) = 0.3625498
*/
char test_dir[] = "test-pagedb-XXXXXX";
mkdtemp(test_dir);
PageDB *db;
int ret = page_db_new(&db, test_dir);
CuAssert(tc,
db!=0? db->error->message: "NULL",
ret == 0);
db->persist = 0;
char *urls[5] = {"1", "2", "3", "4", "5" };
LinkInfo links_1[] = {{"2", 0.1}, {"5", 0.1}};
LinkInfo links_2[] = {{"3", 0.1}, {"5", 0.1}};
LinkInfo links_3[] = {{"4", 0.1}, {"5", 0.1}};
LinkInfo links_4[] = {{"1", 0.1}, {"5", 0.1}};
LinkInfo *links[5] = {
links_1, links_2, links_3, links_4, 0
};
int n_links[5] = {2, 2, 2, 2, 0};
for (int i=0; i<5; ++i) {
CrawledPage *cp = crawled_page_new(urls[i]);
for (int j=0; j<n_links[i]; ++j)
crawled_page_add_link(cp, links[i][j].url, links[i][j].score);
cp->score = i/5.0;
crawled_page_set_hash64(cp, i);
PageInfoList *pil;
CuAssert(tc,
db->error->message,
page_db_add(db, cp, &pil) == 0);
page_info_list_delete(pil);
crawled_page_delete(cp);
}
// Without content scores
// ------------------------------------------------------------------------
PageDBLinkStream *st;
CuAssert(tc,
db->error->message,
page_db_link_stream_new(&st, db) == 0);
st->only_diff_domain = 0;
PageRank *pr;
ret = page_rank_new(&pr, test_dir, 5);
CuAssert(tc,
pr!=0? pr->error->message: "NULL",
ret == 0);
pr->precision = 1e-6;
CuAssert(tc,
pr->error->message,
page_rank_compute(pr,
st,
page_db_link_stream_next,
page_db_link_stream_reset) == 0);
page_db_link_stream_delete(st);
uint64_t idx;
float *score;
float scores[5] = {0.15936255, 0.15936255, 0.15936255, 0.15936255, 0.3625498};
for (int i=0; i<5; ++i) {
CuAssert(tc,
db->error->message,
page_db_get_idx(db, page_db_hash(urls[i]), &idx) == 0);
CuAssertPtrNotNull(tc,
score = mmap_array_idx(pr->value1, idx));
CuAssertDblEquals(tc, scores[i], *score, 1e-6);
}
CHECK_DELETE(tc, pr->error->message, page_rank_delete(pr));
// With content scores, damping = 0
// ------------------------------------------------------------------------
CuAssert(tc,
db->error->message,
page_db_link_stream_new(&st, db) == 0);
st->only_diff_domain = 0;
ret = page_rank_new(&pr, test_dir, 5);
CuAssert(tc,
pr!=0? pr->error->message: "NULL",
ret == 0);
pr->precision = 1e-6;
pr->damping = 0.0;
CuAssert(tc,
db->error->message,
page_db_get_scores(db, &pr->scores) == 0);
CuAssert(tc,
pr->error->message,
page_rank_compute(pr,
st,
page_db_link_stream_next,
page_db_link_stream_reset) == 0);
page_db_link_stream_delete(st);
float total_score = 0.0;
for (int i=0; i<5; ++i)
total_score += scores[i] = *((float*)mmap_array_idx(pr->scores, i));
for (int i=0; i<5; ++i) {
CuAssert(tc,
db->error->message,
page_db_get_idx(db, page_db_hash(urls[i]), &idx) == 0);
CuAssertPtrNotNull(tc,
score = mmap_array_idx(pr->value1, idx));
CuAssertDblEquals(tc, scores[idx]/total_score, *score, 1e-6);
}
CHECK_DELETE(tc, pr->scores->error->message, mmap_array_delete(pr->scores));
CHECK_DELETE(tc, pr->error->message, page_rank_delete(pr));
// With content scores, damping = 0.5
// ------------------------------------------------------------------------
CuAssert(tc,
db->error->message,
page_db_link_stream_new(&st, db) == 0);
st->only_diff_domain = 0;
ret = page_rank_new(&pr, test_dir, 5);
CuAssert(tc,
pr!=0? pr->error->message: "NULL",
ret == 0);
pr->precision = 1e-6;
pr->damping = 0.5;
CuAssert(tc,
db->error->message,
page_db_get_scores(db, &pr->scores) == 0);
CuAssert(tc,
pr->error->message,
page_rank_compute(pr,
st,
page_db_link_stream_next,
page_db_link_stream_reset) == 0);
page_db_link_stream_delete(st);
float expected_pr[] = {
0.06386554621848739,
0.08739495798319329,
0.1647058823529412,
0.25546218487394956,
0.4285714285714286
};
for (int i=0; i<5; ++i) {
CuAssert(tc,
db->error->message,
page_db_get_idx(db, page_db_hash(urls[i]), &idx) == 0);
CuAssertPtrNotNull(tc,
score = mmap_array_idx(pr->value1, idx));
CuAssertDblEquals(tc, expected_pr[i], *score, 1e-6);
}
CHECK_DELETE(tc, pr->scores->error->message, mmap_array_delete(pr->scores));
CHECK_DELETE(tc, pr->error->message, page_rank_delete(pr));
page_db_delete(db);
}
