Function MergeTextIndexWeights

pg_documentdb/src/metadata/index.c:2024–2084

* Merges the weights field with the set of paths used in the key declaration. * If the path is there, it updates the weight. Otherwise, adds the weight * as a new path. * Wildcard weights need special handling. When merging weights, if we are * building the model definition (an IndexDef struct), then we do not add the * wildcard to the weights. This is because the IndexDef is used to construc

 * the spec. So we add the wildcard to the weights.
 */
List *
MergeTextIndexWeights(List *textIndexes, const bson_value_t *weights, bool *isWildCard,
					  bool includeWildCardInWeights)
{
	if (weights->value_type != BSON_TYPE_DOCUMENT)
	{
		ereport(ERROR, (errmsg("weights must be a valid document")));
	}

	bson_iter_t weightsIter;
	BsonValueInitIterator(weights, &weightsIter);

	while (bson_iter_next(&weightsIter))
	{
		const char *weightPath = bson_iter_key(&weightsIter);
		const bson_value_t *currentValue = bson_iter_value(&weightsIter);
		bool isWeightWildCard = false;
		if (!BsonValueIsNumber(currentValue))
		{
			ereport(ERROR, (errcode(ERRCODE_DOCUMENTDB_INVALIDINDEXSPECIFICATIONOPTION),
							errmsg("weight for text index needs numeric type")));
		}

		if (strcmp(weightPath, "$**") == 0)
		{
			isWeightWildCard = true;
			if (isWildCard != NULL)
			{
				*isWildCard |= isWeightWildCard;
			}
		}

		double weight = BsonValueAsDouble(currentValue);

		ListCell *indexCell;
		bool found = false;
		if (textIndexes != NIL)
		{
			foreach(indexCell, textIndexes)
			{
				TextIndexWeights *weightEntry = lfirst(indexCell);
				if (strcmp(weightEntry->path, weightPath) == 0)
				{
					weightEntry->weight = weight;
					found = true;
					break;
				}
			}
		}

		if (!found && (includeWildCardInWeights || !isWeightWildCard))
		{
			TextIndexWeights *weightEntry = palloc0(sizeof(TextIndexWeights));
			weightEntry->path = weightPath;
			weightEntry->weight = weight;
			textIndexes = lappend(textIndexes, weightEntry);
		}
	}