Function BuildUpdates

pg_documentdb/src/commands/update.c:730–770

* Reentrant function that looks at the update spec * and parses the update list OR update sequence of documents * and builds a batch update spec. * This is done as a second pass so that in subsequent changes, * for single shard updates, we can skip the parse stage and just * send the entire spec to the worker. */

 * send the entire spec to the worker.
 */
static void
BuildUpdates(BatchUpdateSpec *spec)
{
	if (spec->updates != NIL)
	{
		return;
	}

	List *updates = NIL;
	if (spec->updateSequence != NULL)
	{
		updates = BuildUpdateSpecListFromSequence(spec->updateSequence, &spec->hasUpsert,
												  &spec->variableSpec);
	}
	else if (spec->updateValue.value_type == BSON_TYPE_ARRAY)
	{
		bson_iter_t updateArrayIter;
		BsonValueInitIterator(&spec->updateValue, &updateArrayIter);
		updates = BuildUpdateSpecList(&updateArrayIter, &spec->hasUpsert,
									  &spec->variableSpec);
	}
	else
	{
		ereport(ERROR, (errcode(ERRCODE_DOCUMENTDB_LOCATION40414),
						errmsg("Required field 'update.updates' is missing")));
	}

	int updateCount = list_length(updates);
	if (updateCount == 0 || updateCount > MaxWriteBatchSize)
	{
		ereport(ERROR, (errcode(ERRCODE_DOCUMENTDB_INVALIDLENGTH),
						errmsg("Batch sizes should always fall between 1 and %d. "
							   "Got %d operations.", MaxWriteBatchSize, updateCount),
						errdetail_log("Batch sizes should always fall between 1 and %d. "
									  "Got %d operations.", MaxWriteBatchSize,
									  updateCount)));
	}

	spec->updates = updates;
	ReportUpdateFeatureUsage(list_length(updates));
}


/*