liquid_feedback_core

annotate lf_update_suggestion_order.c @ 358:e22a4d2aea2d

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Write ranks to database in "lf_update_suggestion_order"
author jbe
date Sun Mar 17 10:40:00 2013 +0100 (2013-03-17)
parents 4698b68e0942
children c37c0b4f2027
rev   line source
jbe@352 1 #include <stdlib.h>
jbe@352 2 #include <stdio.h>
jbe@352 3 #include <string.h>
jbe@352 4 #include <libpq-fe.h>
jbe@352 5 #include <search.h>
jbe@352 6
jbe@352 7 static char *escapeLiteral(PGconn *conn, const char *str, size_t len) {
jbe@352 8 // provides compatibility for PostgreSQL versions prior 9.0
jbe@352 9 // in future: return PQescapeLiteral(conn, str, len);
jbe@352 10 char *res;
jbe@352 11 size_t res_len;
jbe@352 12 res = malloc(2*len+3);
jbe@358 13 if (!res) return NULL;
jbe@352 14 res[0] = '\'';
jbe@352 15 res_len = PQescapeStringConn(conn, res+1, str, len, NULL);
jbe@352 16 res[res_len+1] = '\'';
jbe@352 17 res[res_len+2] = 0;
jbe@352 18 return res;
jbe@352 19 }
jbe@352 20
jbe@352 21 static void freemem(void *ptr) {
jbe@352 22 // to be used for "escapeLiteral" function
jbe@352 23 // provides compatibility for PostgreSQL versions prior 9.0
jbe@352 24 // in future: PQfreemem(ptr);
jbe@352 25 free(ptr);
jbe@352 26 }
jbe@352 27
jbe@352 28 #define COL_MEMBER_ID 0
jbe@352 29 #define COL_WEIGHT 1
jbe@352 30 #define COL_PREFERENCE 2
jbe@352 31 #define COL_SUGGESTION_ID 3
jbe@352 32
jbe@353 33 struct candidate {
jbe@353 34 char *key;
jbe@356 35 double score_per_step;
jbe@356 36 int reaches_score;
jbe@353 37 double score;
jbe@353 38 int seat;
jbe@353 39 };
jbe@353 40
jbe@353 41 static int compare_candidate(struct candidate *c1, struct candidate *c2) {
jbe@353 42 return strcmp(c1->key, c2->key);
jbe@353 43 }
jbe@352 44
jbe@353 45 static int candidate_count;
jbe@353 46 static struct candidate *candidates;
jbe@353 47
jbe@353 48 static void register_candidate(char **candidate_key, VISIT visit, int level) {
jbe@352 49 if (visit == postorder || visit == leaf) {
jbe@353 50 struct candidate *candidate;
jbe@353 51 candidate = candidates + (candidate_count++);
jbe@353 52 candidate->key = *candidate_key;
jbe@353 53 candidate->seat = 0;
jbe@352 54 }
jbe@352 55 }
jbe@352 56
jbe@353 57 static struct candidate *candidate_by_key(char *candidate_key) {
jbe@353 58 struct candidate *candidate;
jbe@353 59 struct candidate compare;
jbe@353 60 compare.key = candidate_key;
jbe@353 61 candidate = bsearch(&compare, candidates, candidate_count, sizeof(struct candidate), (void *)compare_candidate);
jbe@353 62 if (!candidate) {
jbe@356 63 fprintf(stderr, "Candidate not found (should not happen).\n");
jbe@352 64 abort();
jbe@352 65 }
jbe@353 66 return candidate;
jbe@352 67 }
jbe@352 68
jbe@352 69 struct ballot_section {
jbe@352 70 int count;
jbe@353 71 struct candidate **candidates;
jbe@352 72 };
jbe@352 73
jbe@352 74 struct ballot {
jbe@352 75 int weight;
jbe@352 76 struct ballot_section sections[4];
jbe@352 77 };
jbe@352 78
jbe@356 79 static struct candidate *loser(int round_number, struct ballot *ballots, int ballot_count) {
jbe@356 80 int i, j, k;
jbe@356 81 int remaining;
jbe@356 82 for (i=0; i<candidate_count; i++) {
jbe@356 83 candidates[i].score = 0.0;
jbe@356 84 }
jbe@356 85 remaining = candidate_count - round_number;
jbe@356 86 while (1) {
jbe@356 87 double scale;
jbe@356 88 if (remaining <= 1) break;
jbe@356 89 for (i=0; i<candidate_count; i++) {
jbe@356 90 candidates[i].score_per_step = 0.0;
jbe@356 91 candidates[i].reaches_score = 0;
jbe@356 92 }
jbe@356 93 for (i=0; i<ballot_count; i++) {
jbe@356 94 for (j=0; j<4; j++) {
jbe@356 95 int matches = 0;
jbe@356 96 for (k=0; k<ballots[i].sections[j].count; k++) {
jbe@356 97 struct candidate *candidate;
jbe@356 98 candidate = ballots[i].sections[j].candidates[k];
jbe@356 99 if (candidate->score < 1.0 && !candidate->seat) matches++;
jbe@356 100 }
jbe@356 101 if (matches) {
jbe@356 102 double score_inc;
jbe@356 103 score_inc = 1.0 / (double)matches;
jbe@356 104 for (k=0; k<ballots[i].sections[j].count; k++) {
jbe@356 105 struct candidate *candidate;
jbe@356 106 candidate = ballots[i].sections[j].candidates[k];
jbe@356 107 if (candidate->score < 1.0 && !candidate->seat) {
jbe@356 108 candidate->score_per_step += score_inc;
jbe@356 109 }
jbe@356 110 }
jbe@356 111 break;
jbe@356 112 }
jbe@356 113 }
jbe@356 114 }
jbe@356 115 scale = (double)candidate_count;
jbe@356 116 for (i=0; i<candidate_count; i++) {
jbe@356 117 double max_scale;
jbe@356 118 if (candidates[i].score_per_step > 0.0) {
jbe@356 119 max_scale = (1.0-candidates[i].score) / candidates[i].score_per_step;
jbe@356 120 if (max_scale <= scale) {
jbe@356 121 scale = max_scale;
jbe@356 122 candidates[i].reaches_score = 1;
jbe@356 123 }
jbe@356 124 }
jbe@356 125 }
jbe@356 126 for (i=0; i<candidate_count; i++) {
jbe@356 127 if (candidates[i].score_per_step > 0.0) {
jbe@356 128 if (candidates[i].reaches_score) {
jbe@356 129 candidates[i].score = 1.0;
jbe@356 130 remaining--;
jbe@356 131 } else {
jbe@356 132 candidates[i].score += scale * candidates[i].score_per_step;
jbe@356 133 if (candidates[i].score >= 1.0) remaining--;
jbe@356 134 }
jbe@356 135 if (remaining <= 1) break;
jbe@356 136 }
jbe@356 137 }
jbe@356 138 }
jbe@356 139 for (i=candidate_count-1; i>=0; i--) {
jbe@356 140 if (candidates[i].score < 1.0 && !candidates[i].seat) return candidates+i;
jbe@356 141 }
jbe@356 142 fprintf(stderr, "No remaining candidate (should not happen).");
jbe@356 143 abort();
jbe@356 144 }
jbe@356 145
jbe@358 146 static int write_ranks(PGconn *db, char *escaped_initiative_id) {
jbe@358 147 PGresult *res;
jbe@358 148 char *cmd;
jbe@358 149 int i;
jbe@358 150 if (asprintf(&cmd, "BEGIN; UPDATE \"suggestion\" SET \"proportional_order\" = NULL WHERE \"initiative_id\" = %s", escaped_initiative_id) < 0) {
jbe@358 151 fprintf(stderr, "Could not prepare query string in memory.\n");
jbe@358 152 abort();
jbe@358 153 }
jbe@358 154 res = PQexec(db, cmd);
jbe@358 155 free(cmd);
jbe@358 156 if (!res) {
jbe@358 157 fprintf(stderr, "Error in pqlib while sending SQL command to initiate suggestion update.\n");
jbe@358 158 return 1;
jbe@358 159 } else if (
jbe@358 160 PQresultStatus(res) != PGRES_COMMAND_OK &&
jbe@358 161 PQresultStatus(res) != PGRES_TUPLES_OK
jbe@358 162 ) {
jbe@358 163 fprintf(stderr, "Error while executing SQL command to initiate suggestion update:\n%s", PQresultErrorMessage(res));
jbe@358 164 PQclear(res);
jbe@358 165 return 1;
jbe@358 166 } else {
jbe@358 167 PQclear(res);
jbe@358 168 }
jbe@358 169 for (i=0; i<candidate_count; i++) {
jbe@358 170 char *escaped_suggestion_id;
jbe@358 171 escaped_suggestion_id = escapeLiteral(db, candidates[i].key, strlen(candidates[i].key));
jbe@358 172 if (!escaped_suggestion_id) {
jbe@358 173 fprintf(stderr, "Could not escape literal in memory.\n");
jbe@358 174 abort();
jbe@358 175 }
jbe@358 176 if (asprintf(&cmd, "UPDATE \"suggestion\" SET \"proportional_order\" = %i WHERE \"id\" = %s", candidates[i].seat, escaped_suggestion_id) < 0) {
jbe@358 177 fprintf(stderr, "Could not prepare query string in memory.\n");
jbe@358 178 abort();
jbe@358 179 }
jbe@358 180 freemem(escaped_suggestion_id);
jbe@358 181 res = PQexec(db, cmd);
jbe@358 182 free(cmd);
jbe@358 183 if (!res) {
jbe@358 184 fprintf(stderr, "Error in pqlib while sending SQL command to update suggestion order.\n");
jbe@358 185 } else if (
jbe@358 186 PQresultStatus(res) != PGRES_COMMAND_OK &&
jbe@358 187 PQresultStatus(res) != PGRES_TUPLES_OK
jbe@358 188 ) {
jbe@358 189 fprintf(stderr, "Error while executing SQL command to update suggestion order:\n%s", PQresultErrorMessage(res));
jbe@358 190 PQclear(res);
jbe@358 191 } else {
jbe@358 192 PQclear(res);
jbe@358 193 continue;
jbe@358 194 }
jbe@358 195 res = PQexec(db, "ROLLBACK");
jbe@358 196 if (res) PQclear(res);
jbe@358 197 return 1;
jbe@358 198 }
jbe@358 199 res = PQexec(db, "COMMIT");
jbe@358 200 if (!res) {
jbe@358 201 fprintf(stderr, "Error in pqlib while sending SQL command to commit transaction.\n");
jbe@358 202 return 1;
jbe@358 203 } else if (
jbe@358 204 PQresultStatus(res) != PGRES_COMMAND_OK &&
jbe@358 205 PQresultStatus(res) != PGRES_TUPLES_OK
jbe@358 206 ) {
jbe@358 207 fprintf(stderr, "Error while executing SQL command to commit transaction:\n%s", PQresultErrorMessage(res));
jbe@358 208 PQclear(res);
jbe@358 209 return 1;
jbe@358 210 } else {
jbe@358 211 PQclear(res);
jbe@358 212 return 0;
jbe@358 213 }
jbe@358 214 }
jbe@358 215
jbe@358 216 static int process_initiative(PGconn *db, PGresult *res, char *escaped_initiative_id) {
jbe@358 217 int err;
jbe@352 218 int ballot_count = 0;
jbe@356 219 struct ballot *ballots;
jbe@355 220 int i;
jbe@355 221 {
jbe@355 222 void *candidate_tree = NULL;
jbe@355 223 int tuple_count;
jbe@355 224 char *old_member_id = NULL;
jbe@355 225 struct ballot *ballot;
jbe@355 226 int candidates_in_sections[4] = {0, };
jbe@355 227 candidate_count = 0;
jbe@355 228 tuple_count = PQntuples(res);
jbe@355 229 for (i=0; i<=tuple_count; i++) {
jbe@355 230 char *member_id, *suggestion_id;
jbe@355 231 if (i<tuple_count) {
jbe@355 232 member_id = PQgetvalue(res, i, COL_MEMBER_ID);
jbe@355 233 suggestion_id = PQgetvalue(res, i, COL_SUGGESTION_ID);
jbe@355 234 if (!candidate_tree || !tfind(suggestion_id, &candidate_tree, (void *)strcmp)) {
jbe@355 235 candidate_count++;
jbe@355 236 if (!tsearch(suggestion_id, &candidate_tree, (void *)strcmp)) {
jbe@356 237 fprintf(stderr, "Insufficient memory while inserting into candidate tree.\n");
jbe@355 238 abort();
jbe@355 239 }
jbe@352 240 }
jbe@352 241 }
jbe@355 242 if (i==tuple_count || (old_member_id && strcmp(old_member_id, member_id))) {
jbe@355 243 ballot_count++;
jbe@355 244 }
jbe@355 245 old_member_id = member_id;
jbe@352 246 }
jbe@355 247 printf("Candidate count: %i\n", candidate_count);
jbe@355 248 candidates = malloc(candidate_count * sizeof(struct candidate));
jbe@355 249 if (!candidates) {
jbe@356 250 fprintf(stderr, "Insufficient memory while creating candidate list.\n");
jbe@353 251 abort();
jbe@352 252 }
jbe@355 253 candidate_count = 0;
jbe@355 254 twalk(candidate_tree, (void *)register_candidate);
jbe@355 255 while (candidate_tree) tdelete(*(void **)candidate_tree, &candidate_tree, (void *)strcmp);
jbe@355 256 printf("Ballot count: %i\n", ballot_count);
jbe@355 257 ballots = calloc(ballot_count, sizeof(struct ballot));
jbe@355 258 if (!ballots) {
jbe@356 259 fprintf(stderr, "Insufficient memory while creating ballot list.\n");
jbe@353 260 abort();
jbe@352 261 }
jbe@355 262 ballot = ballots;
jbe@355 263 for (i=0; i<tuple_count; i++) {
jbe@355 264 char *member_id, *suggestion_id;
jbe@355 265 int weight, preference;
jbe@352 266 member_id = PQgetvalue(res, i, COL_MEMBER_ID);
jbe@352 267 suggestion_id = PQgetvalue(res, i, COL_SUGGESTION_ID);
jbe@355 268 weight = (int)strtol(PQgetvalue(res, i, COL_WEIGHT), (char **)NULL, 10);
jbe@355 269 if (weight <= 0) {
jbe@356 270 fprintf(stderr, "Unexpected weight value.\n");
jbe@358 271 free(ballots);
jbe@358 272 free(candidates);
jbe@358 273 return 1;
jbe@355 274 }
jbe@352 275 preference = (int)strtol(PQgetvalue(res, i, COL_PREFERENCE), (char **)NULL, 10);
jbe@352 276 if (preference < 1 || preference > 4) {
jbe@356 277 fprintf(stderr, "Unexpected preference value.\n");
jbe@358 278 free(ballots);
jbe@358 279 free(candidates);
jbe@358 280 return 1;
jbe@352 281 }
jbe@352 282 preference--;
jbe@355 283 ballot->weight = weight;
jbe@355 284 ballot->sections[preference].count++;
jbe@355 285 if (old_member_id && strcmp(old_member_id, member_id)) ballot++;
jbe@355 286 old_member_id = member_id;
jbe@355 287 }
jbe@355 288 for (i=0; i<ballot_count; i++) {
jbe@355 289 int j;
jbe@355 290 for (j=0; j<4; j++) {
jbe@355 291 if (ballots[i].sections[j].count) {
jbe@355 292 ballots[i].sections[j].candidates = malloc(ballots[i].sections[j].count * sizeof(struct candidate *));
jbe@355 293 if (!ballots[i].sections[j].candidates) {
jbe@356 294 fprintf(stderr, "Insufficient memory while creating ballot section.\n");
jbe@355 295 abort();
jbe@355 296 }
jbe@355 297 }
jbe@355 298 }
jbe@352 299 }
jbe@355 300 ballot = ballots;
jbe@355 301 for (i=0; i<=tuple_count; i++) {
jbe@355 302 char *member_id, *suggestion_id;
jbe@355 303 int preference;
jbe@355 304 if (i<tuple_count) {
jbe@355 305 member_id = PQgetvalue(res, i, COL_MEMBER_ID);
jbe@355 306 suggestion_id = PQgetvalue(res, i, COL_SUGGESTION_ID);
jbe@355 307 preference = (int)strtol(PQgetvalue(res, i, COL_PREFERENCE), (char **)NULL, 10);
jbe@355 308 preference--;
jbe@355 309 ballot->sections[preference].candidates[candidates_in_sections[preference]++] = candidate_by_key(suggestion_id);
jbe@355 310 }
jbe@355 311 if (i==tuple_count || (old_member_id && strcmp(old_member_id, member_id))) {
jbe@355 312 ballot++;
jbe@355 313 candidates_in_sections[0] = 0;
jbe@355 314 candidates_in_sections[1] = 0;
jbe@355 315 candidates_in_sections[2] = 0;
jbe@355 316 candidates_in_sections[3] = 0;
jbe@355 317 }
jbe@355 318 old_member_id = member_id;
jbe@352 319 }
jbe@352 320 }
jbe@355 321
jbe@356 322 for (i=0; i<candidate_count; i++) {
jbe@356 323 struct candidate *candidate = loser(i, ballots, ballot_count);
jbe@356 324 candidate->seat = candidate_count - i;
jbe@358 325 printf("Assigning rank #%i to suggestion #%s.\n", candidate_count - i, candidate->key);
jbe@356 326 }
jbe@356 327
jbe@354 328 for (i=0; i<ballot_count; i++) {
jbe@354 329 int j;
jbe@354 330 for (j=0; j<4; j++) {
jbe@354 331 if (ballots[i].sections[j].count) {
jbe@354 332 free(ballots[i].sections[j].candidates);
jbe@354 333 }
jbe@354 334 }
jbe@354 335 }
jbe@354 336 free(ballots);
jbe@358 337
jbe@358 338 printf("Writing ranks to database.\n");
jbe@358 339 err = write_ranks(db, escaped_initiative_id);
jbe@358 340 printf("Done.\n");
jbe@358 341
jbe@358 342 free(candidates);
jbe@358 343
jbe@358 344 return err;
jbe@352 345 }
jbe@352 346
jbe@352 347 int main(int argc, char **argv) {
jbe@352 348
jbe@352 349 // variable declarations:
jbe@352 350 int err = 0;
jbe@352 351 int i, count;
jbe@352 352 char *conninfo;
jbe@352 353 PGconn *db;
jbe@352 354 PGresult *res;
jbe@352 355
jbe@352 356 // parse command line:
jbe@352 357 if (argc == 0) return 1;
jbe@352 358 if (argc == 1 || !strcmp(argv[1], "-h") || !strcmp(argv[1], "--help")) {
jbe@352 359 FILE *out;
jbe@352 360 out = argc == 1 ? stderr : stdout;
jbe@352 361 fprintf(stdout, "\n");
jbe@352 362 fprintf(stdout, "Usage: %s <conninfo>\n", argv[0]);
jbe@352 363 fprintf(stdout, "\n");
jbe@352 364 fprintf(stdout, "<conninfo> is specified by PostgreSQL's libpq,\n");
jbe@352 365 fprintf(stdout, "see http://www.postgresql.org/docs/9.1/static/libpq-connect.html\n");
jbe@352 366 fprintf(stdout, "\n");
jbe@352 367 fprintf(stdout, "Example: %s dbname=liquid_feedback\n", argv[0]);
jbe@352 368 fprintf(stdout, "\n");
jbe@352 369 return argc == 1 ? 1 : 0;
jbe@352 370 }
jbe@352 371 {
jbe@352 372 size_t len = 0;
jbe@352 373 for (i=1; i<argc; i++) len += strlen(argv[i]) + 1;
jbe@352 374 conninfo = malloc(len * sizeof(char));
jbe@352 375 if (!conninfo) {
jbe@358 376 fprintf(stderr, "Error: Could not allocate memory for conninfo string.\n");
jbe@358 377 abort();
jbe@352 378 }
jbe@352 379 conninfo[0] = 0;
jbe@352 380 for (i=1; i<argc; i++) {
jbe@352 381 if (i>1) strcat(conninfo, " ");
jbe@352 382 strcat(conninfo, argv[i]);
jbe@352 383 }
jbe@352 384 }
jbe@352 385
jbe@352 386 // connect to database:
jbe@352 387 db = PQconnectdb(conninfo);
jbe@352 388 if (!db) {
jbe@358 389 fprintf(stderr, "Error: Could not create database handle.\n");
jbe@352 390 return 1;
jbe@352 391 }
jbe@352 392 if (PQstatus(db) != CONNECTION_OK) {
jbe@352 393 fprintf(stderr, "Could not open connection:\n%s", PQerrorMessage(db));
jbe@352 394 return 1;
jbe@352 395 }
jbe@352 396
jbe@352 397 // check initiatives:
jbe@352 398 res = PQexec(db, "SELECT \"initiative_id\", \"final\" FROM \"initiative_suggestion_order_calculation\"");
jbe@352 399 if (!res) {
jbe@358 400 fprintf(stderr, "Error in pqlib while sending SQL command selecting initiatives to process.\n");
jbe@352 401 err = 1;
jbe@352 402 } else if (PQresultStatus(res) != PGRES_TUPLES_OK) {
jbe@358 403 fprintf(stderr, "Error while executing SQL command selecting initiatives to process:\n%s", PQresultErrorMessage(res));
jbe@352 404 err = 1;
jbe@352 405 PQclear(res);
jbe@352 406 } else {
jbe@352 407 count = PQntuples(res);
jbe@352 408 printf("Number of initiatives to process: %i\n", count);
jbe@352 409 for (i=0; i<count; i++) {
jbe@352 410 char *initiative_id, *escaped_initiative_id;
jbe@352 411 char *cmd;
jbe@352 412 PGresult *res2;
jbe@352 413 initiative_id = PQgetvalue(res, i, 0);
jbe@352 414 printf("Processing initiative_id: %s\n", initiative_id);
jbe@352 415 escaped_initiative_id = escapeLiteral(db, initiative_id, strlen(initiative_id));
jbe@358 416 if (!escaped_initiative_id) {
jbe@358 417 fprintf(stderr, "Could not escape literal in memory.\n");
jbe@358 418 abort();
jbe@358 419 }
jbe@352 420 if (asprintf(&cmd, "SELECT \"member_id\", \"weight\", \"preference\", \"suggestion_id\" FROM \"individual_suggestion_ranking\" WHERE \"initiative_id\" = %s ORDER BY \"member_id\", \"preference\"", escaped_initiative_id) < 0) {
jbe@352 421 fprintf(stderr, "Could not prepare query string in memory.\n");
jbe@355 422 abort();
jbe@352 423 }
jbe@352 424 res2 = PQexec(db, cmd);
jbe@352 425 free(cmd);
jbe@352 426 if (!res2) {
jbe@358 427 fprintf(stderr, "Error in pqlib while sending SQL command selecting individual suggestion rankings.\n");
jbe@352 428 err = 1;
jbe@352 429 } else if (PQresultStatus(res2) != PGRES_TUPLES_OK) {
jbe@358 430 fprintf(stderr, "Error while executing SQL command selecting individual suggestion rankings:\n%s", PQresultErrorMessage(res));
jbe@352 431 err = 1;
jbe@352 432 PQclear(res2);
jbe@356 433 } else if (PQnfields(res2) < 4) {
jbe@358 434 fprintf(stderr, "Too few columns returned by SQL command selecting individual suggestion rankings.\n");
jbe@356 435 err = 1;
jbe@356 436 PQclear(res2);
jbe@352 437 } else {
jbe@352 438 if (PQntuples(res2) == 0) {
jbe@352 439 printf("Nothing to do.\n");
jbe@352 440 } else {
jbe@358 441 if (process_initiative(db, res2, escaped_initiative_id)) err = 1;
jbe@352 442 }
jbe@352 443 PQclear(res2);
jbe@352 444 }
jbe@352 445 freemem(escaped_initiative_id);
jbe@352 446 }
jbe@352 447 PQclear(res);
jbe@352 448 }
jbe@352 449
jbe@352 450 // cleanup and exit
jbe@352 451 PQfinish(db);
jbe@358 452 if (!err) printf("Successfully terminated.\n");
jbe@358 453 else fprintf(stderr, "Exiting with error code #%i.\n", err);
jbe@352 454 return err;
jbe@352 455
jbe@352 456 }

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