Scala Dependency Injection and testing -

i looking @ alternatives(constructor params, di, etc) in following scenario. have integration test begins simple database entries, , tests etl pipeline transform entries. db connections needed within etl class tree, per actual program, in integration test class input original data. ive tried provide separate db access test class , etl lock errors. struggling best way go this

a quick unit test looks this:

class mytest extends testlibrary dbtestsupport {    db.find("foo")...  } trait dbtestsuport {  //setup  val db = externallibrary.database(port=800).open } 

but want full integration test mock/test db , have contend kinds of inheritance.

class myfunctionaltest extends testlibrary {   //somehow access db   def addsometestdata = db.add(it: list[foo])   val items = list(foo(1), foo(2))   addsometestdata(items)  //now lets test etl pipeline   def transform = new transform().methodthatdoesthings...//  transform.testmethodtoexpectthings//  } 

where db access needed way further down:

class transform {   def methodthatdoesthings = {    stream.via(new coolstreammethod)   //... } class coolstreammethod {  //setup  //**somehow need access dao  dao.myquery map { results =>   process(results)  } } class actordao {  val actor = //create actor router forwards workers  def myquery = actor ? coolquery } class worker extends actor {  dao = //get access dao implementation  def receive = {   case q: coolquery => dao.find(q.thing) } class daoimpl {  def find(item: bar) = db.find("item.id") // **database specific stuff externallibrary.database method needed in original unit test }