Use one PG connection, add support for connection params

message/store.go

@@ -25,7 +25,6 @@ var errNoRows = errors.New("no rows found")
 type Store interface {
 	AddMessage(m *model.Message) error
 	AddMessages(ms []*model.Message) error
-	DB() *sql.DB
 	Message(id string) (*model.Message, error)
 	MessageCounts() (map[string]int, error)
 	Messages(topic string, since model.SinceMarker, scheduled bool) ([]*model.Message, error)
@@ -99,11 +98,6 @@ func newCommonStore(db *sql.DB, queries storeQueries, batchSize int, batchTimeou
 	return c
 }
 
-// DB returns the underlying database connection
-func (c *commonStore) DB() *sql.DB {
-	return c.db
-}
-
 // AddMessage stores a message to the message cache synchronously, or queues it to be stored at a later date asynchronously.
 func (c *commonStore) AddMessage(m *model.Message) error {
 	if c.queue != nil {