cachedb_mongodb: Implement the "truncate" capability

modules/cachedb_mongodb/cachedb_mongodb.c

@@ -121,6 +121,7 @@ static int mod_init(void)
 	cde.cdb_func.set_cols = mongo_con_set_cols;
 	cde.cdb_func.unset_cols = mongo_con_unset_cols;
 	cde.cdb_func.raw_query = mongo_con_raw_query;
+	cde.cdb_func.truncate = mongo_truncate;
 	cde.cdb_func.db_query_trans = mongo_db_query_trans;
 	cde.cdb_func.db_free_trans = mongo_db_free_result_trans;
 	cde.cdb_func.db_insert_trans = mongo_db_insert_trans;

modules/cachedb_mongodb/cachedb_mongodb_dbase.c

@@ -1627,6 +1627,25 @@ int mongo_db_update_trans(cachedb_con *con, const str *table,
 	return -1;
 }
 
+int mongo_truncate(cachedb_con *con)
+{
+	bson_t empty_doc = BSON_INITIALIZER;
+	bson_error_t error;
+	struct timeval start;
+	int ret = 0;
+
+	start_expire_timer(start, mongo_exec_threshold);
+	if (!mongoc_collection_remove(MONGO_COLLECTION(con),
+	                         MONGOC_REMOVE_NONE, &empty_doc, NULL, &error)) {
+		LM_ERR("failed to truncate con %.*s!\n", con->url.len, con->url.s);
+		ret = -1;
+	}
+	stop_expire_timer(start, mongo_exec_threshold, "MongoDB truncate",
+	                  con->url.s, con->url.len, 0);
+
+	return ret;
+}
+
 int mongo_doc_to_dict(const bson_t *doc, cdb_dict_t *out_dict)
 {
 	bson_iter_t iter;

modules/cachedb_mongodb/cachedb_mongodb_dbase.h

@@ -91,6 +91,7 @@ int mongo_db_update_trans(cachedb_con *con, const str *table,
                           const db_key_t *_k, const db_op_t *_o,
                           const db_val_t *_v, const db_key_t *_uk,
                           const db_val_t *_uv, const int _n, const int _un);
+int mongo_truncate(cachedb_con *con);
 
 int mongo_con_get_rows(cachedb_con *con, const cdb_filter_t *row_filter,
                        cdb_res_t *res);