Function ParseRequired

pg_documentdb/src/jsonschema/bson_json_schema_tree.c:455–520

* This function reads the schema value for "required" keyword. * And stores it in the parent Node's Object validations section. */

 * And stores it in the parent Node's Object validations section.
 */
static void
ParseRequired(const bson_value_t *value, SchemaNode *node)
{
	if (value->value_type != BSON_TYPE_ARRAY)
	{
		ereport(ERROR, (errcode(ERRCODE_DOCUMENTDB_TYPEMISMATCH),
						errmsg(
							"Expected an array for 'required' in $jsonSchema, but got %s",
							BsonTypeName(value->value_type))));
	}
	pgbson_writer writer;
	PgbsonWriterInit(&writer);
	pgbson_array_writer arrayWriter;
	PgbsonWriterStartArray(&writer, "", 0, &arrayWriter);
	bson_iter_t iter;
	BsonValueInitIterator(value, &iter);

	/* Hash table to track seen field names for efficient duplicate detection */
	HTAB *seenFieldsHash = CreateStringViewHashSet();

	while (bson_iter_next(&iter))
	{
		if (!BSON_ITER_HOLDS_UTF8(&iter))
		{
			ereport(ERROR, (errcode(ERRCODE_DOCUMENTDB_TYPEMISMATCH),
							errmsg(
								"All elements in 'required' array must be strings, but encountered %s",
								BsonIterTypeName(&iter))));
		}
		const char *field = bson_iter_utf8(&iter, NULL);

		/* TODO: Add support for dot notation paths */
		if (strchr(field, '.') != NULL)
		{
			ereport(ERROR, (errcode(ERRCODE_DOCUMENTDB_FAILEDTOPARSE),
							errmsg("Dot notation paths are currently not supported: %s",
								   field)));
		}

		/* Check for duplicate field names using hash table */
		StringView fieldView = CreateStringViewFromString(field);
		bool found;
		hash_search(seenFieldsHash, &fieldView, HASH_ENTER, &found);

		if (found)
		{
			hash_destroy(seenFieldsHash);
			PgbsonWriterFree(&writer);
			ereport(ERROR, (errcode(ERRCODE_DOCUMENTDB_FAILEDTOPARSE),
							errmsg(
								"Duplicate field name in $jsonSchema 'required' array")));
		}

		PgbsonArrayWriterWriteUtf8(&arrayWriter, field);
	}

	/* Clean up hash table */
	hash_destroy(seenFieldsHash);