/*
* PgQ log trigger, takes 2 arguments:
* 1. queue name to be inserted to.
*
* Queue events will be in format:
* ev_type - operation type, I/U/D
* ev_data - urlencoded column values
* ev_extra1 - table name
* ev_extra2 - optional urlencoded backup
*/
Datum pgq_logutriga(PG_FUNCTION_ARGS)
{
TriggerData *tg;
struct PgqTriggerEvent ev;
HeapTuple row;
/*
* Get the trigger call context
*/
if (!CALLED_AS_TRIGGER(fcinfo))
elog(ERROR, "pgq.logutriga not called as trigger");
tg = (TriggerData *)(fcinfo->context);
if (TRIGGER_FIRED_BY_UPDATE(tg->tg_event))
row = tg->tg_newtuple;
else
row = tg->tg_trigtuple;
if (pgq_is_logging_disabled())
goto skip_it;
/*
* Connect to the SPI manager
*/
if (SPI_connect() < 0)
elog(ERROR, "logutriga: SPI_connect() failed");
pgq_prepare_event(&ev, tg, true);
appendStringInfoChar(ev.field[EV_TYPE], ev.op_type);
appendStringInfoChar(ev.field[EV_TYPE], ':');
appendStringInfoString(ev.field[EV_TYPE], ev.pkey_list);
appendStringInfoString(ev.field[EV_EXTRA1], ev.info->table_name);
if (is_interesting_change(&ev, tg)) {
/*
* create type, data
*/
pgq_urlenc_row(&ev, row, ev.field[EV_DATA]);
/*
* Construct the parameter array and insert the log row.
*/
pgq_insert_tg_event(&ev);
}
if (SPI_finish() < 0)
elog(ERROR, "SPI_finish failed");
/*
* After trigger ignores result,
* before trigger skips event if NULL.
*/
skip_it:
if (TRIGGER_FIRED_AFTER(tg->tg_event) || ev.tgargs->skip)
return PointerGetDatum(NULL);
else
return PointerGetDatum(row);
}
/*
* parse trigger arguments.
*/
void pgq_prepare_event(struct PgqTriggerEvent *ev, TriggerData *tg, bool newstyle)
{
memset(ev, 0, sizeof(*ev));
/*
* Check trigger calling conventions
*/
if (TRIGGER_FIRED_BY_TRUNCATE(tg->tg_event)) {
if (!TRIGGER_FIRED_FOR_STATEMENT(tg->tg_event))
elog(ERROR, "pgq tRuncate trigger must be fired FOR EACH STATEMENT");
} else if (!TRIGGER_FIRED_FOR_ROW(tg->tg_event)) {
elog(ERROR, "pgq Ins/Upd/Del trigger must be fired FOR EACH ROW");
}
if (tg->tg_trigger->tgnargs < 1)
elog(ERROR, "pgq trigger must have destination queue as argument");
/*
* check operation type
*/
if (TRIGGER_FIRED_BY_INSERT(tg->tg_event))
ev->op_type = 'I';
else if (TRIGGER_FIRED_BY_UPDATE(tg->tg_event))
ev->op_type = 'U';
else if (TRIGGER_FIRED_BY_DELETE(tg->tg_event))
ev->op_type = 'D';
else if (TRIGGER_FIRED_BY_TRUNCATE(tg->tg_event))
ev->op_type = 'R';
else
elog(ERROR, "unknown event for pgq trigger");
/*
* load table info
*/
ev->tgdata = tg;
ev->info = find_table_info(tg->tg_relation);
ev->table_name = ev->info->table_name;
ev->pkey_list = ev->info->pkey_list;
ev->queue_name = tg->tg_trigger->tgargs[0];
/*
* parse args, newstyle args are cached
*/
ev->tgargs = find_trigger_info(ev->info, tg->tg_trigger->tgoid, true);
if (newstyle) {
if (!ev->tgargs->finalized)
parse_newstyle_args(ev, tg);
if (ev->tgargs->pkey_list)
ev->pkey_list = ev->tgargs->pkey_list;
/* Check if we have pkey */
if (ev->op_type == 'U' || ev->op_type == 'D') {
if (ev->pkey_list[0] == 0)
elog(ERROR, "Update/Delete on table without pkey");
}
} else {
parse_oldstyle_args(ev, tg);
}
ev->tgargs->finalized = true;
/*
* Check if BEFORE/AFTER makes sense.
*/
if (ev->tgargs->skip) {
if (TRIGGER_FIRED_AFTER(tg->tg_event))
elog(ERROR, "SKIP does not work in AFTER trigger.");
} else {
if (!TRIGGER_FIRED_AFTER(tg->tg_event))
/* dont care ??? */ ;
}
if (ev->tgargs->deny) {
elog(ERROR, "Table '%s' to queue '%s': change not allowed (%c)",
ev->table_name, ev->queue_name, ev->op_type);
}
/*
* init data
*/
ev->field[EV_TYPE] = pgq_init_varbuf();
ev->field[EV_DATA] = pgq_init_varbuf();
ev->field[EV_EXTRA1] = pgq_init_varbuf();
/*
* Do the backup, if requested.
*/
if (ev->tgargs->backup) {
ev->field[EV_EXTRA2] = pgq_init_varbuf();
pgq_urlenc_row(ev, tg->tg_trigtuple, ev->field[EV_EXTRA2]);
}
}
