GetConfig get global config.

GetConfigFromEtcd get and update global configuration from etcd.

GetDB get global database conn.

GetEtcdClient get global etcd client.

GetGRPCServerConfig get grpc server configuration.

InitDBForTest init and inject database connection for test.

SetEtcdClient set glocal etcd client.

SetGRPCServerConfig set grpc server configuration.

WatchConfig watch configuration.

ErrDBObjNull indicate DB Object is nil.

Config configuration of campaign.