How to write unit test for below:
def processDbOutput(dbConfigObject, tuple):
dbConn = DBConnectionProvider(dbConfigObject.dbServer)
res=dbConn.excecute(......)
Want to write unit test for processDbOutput method accepting parameters.
And also mock the dbConn inside the method.
(update) The processDbOutput method is target method for multiprocessing. So it is good practice to create and close db connection within the same method. (Correct me if I am wrong).
Thanks in advance.
Your processDbOutput has two responsibilities. One is create db connection, and another is execute something.
It's recommended to split this function like below:
def connectDb(dbConfigObject):
return DBConnectionProvider(dbConfigObject.dbServer)
def executeDb(dbConn, tuple):
res=dbConn.execute(......)
Then, you can test executeDb with mock, dbConn.
If you are re-structuring your code for testing, your code will be more beautiful.
I think that 정도유's answer can still apply. I still think the answer is dependency injection, but I would inject a function to initialize the connection:
def connectDb(dbConfigObject):
return DBConnectionProvider(dbConfigObject.dbServer)
def executeDb(initializeDB, tuple):
dbConn = initializeDB()
res=dbConn.execute(......)
This enables your test to provide a dummy dbConn object for unit testing instead of patching. Then your production code can use DBConnectionProvider() directly:
def test_executeDb(self):
m = MagicMock()
# configure m.execute.return_value, etc
def initialize_stub():
return m
executeDb(initialize_stub, m)
# assertion
DBConnectionProvider(and thusdbConn), you can test the parametersexecuteis called with. Other than that, it is diffcult to guess what you want to do. Best you show us your test code (even if it is not working) to better describe your problem.mock.patch), but I want to know what do you want to test. E.g. can you write an example test with some assertions to show what you are going to test inprocessDbOutput?