| Copyright | (c) 2014 Edward L. Blake |
|---|---|
| License | BSD-style |
| Maintainer | Edward L. Blake <edwardlblake@gmail.com> |
| Stability | experimental |
| Portability | portable |
| Safe Haskell | Safe |
| Language | Haskell98 |
Caching.ExpiringCacheMap.Utils.TestSequence
Description
TestSequence monad for testing caching behaviour.
{-# LANGUAGE OverloadedStrings #-}
import Caching.ExpiringCacheMap.HashECM (newECMForM, lookupECM, CacheSettings(..), consistentDuration)
import qualified Caching.ExpiringCacheMap.Utils.TestSequence as TestSeq
import qualified Data.ByteString.Char8 as BS
test = do
(TestSeq.TestSequenceState (_, events, _), return_value) <- TestSeq.runTestSequence test'
(putStrLn . show . reverse) events
return ()
where
test' = do
filecache <- newECMForM
(consistentDuration 100 -- Duration between access and expiry time of each item, no state needed.
(\state _id -> do number <- TestSeq.readNumber
return (state, number)))
(TestSeq.getCurrentTime >>= return)
12000 -- Time check frequency: (accumulator `mod` this_number) == 0.
(CacheWithLRUList
6 -- Expected size of key-value map when removing elements.
6 -- Size of map when to remove items from key-value map.
12 -- Size of list when to compact
)
TestSeq.newTestSVar TestSeq.enterTestSVar TestSeq.readTestSVar
-- Use lookupECM whenever the contents of "file1" is needed.
b <- lookupECM filecache ("file1" :: BS.ByteString)
TestSeq.haveNumber b
b <- lookupECM filecache "file1"
b <- lookupECM filecache "file2"
TestSeq.haveNumber b
return b
Evaluating the test function results in a list of events.
>>>test[GetVar 3,ReadNumber 4,GetTime 7,PutVar 11,HaveNumber 4,GetVar 14,PutVar 17, GetVar 19,ReadNumber 20,GetTime 23,PutVar 27,HaveNumber 20]
In this example the history shows 2 time accesses (GetTime 7 and
GetTime 23) since the time check frequency number is a high value (12000),
but regardless the high value a time check is still requested again because
of the new key request for "file2".
Changing the time frequency to 1 will alter the list of events with more frequent time checks:
>>>test[GetVar 3,ReadNumber 4,GetTime 7,PutVar 11,HaveNumber 4,GetVar 14,GetTime 15, GetTime 18,PutVar 22,GetVar 24,ReadNumber 25,GetTime 28,PutVar 32, HaveNumber 25]
Documentation
runTestSequence :: Show a => TestSequence b a -> IO (TestSequenceState b, a) #
newTestSVar :: a -> TestSequence a (TestSVar a) #
enterTestSVar :: TestSVar a -> (a -> TestSequence a (a, b)) -> TestSequence a b #
readTestSVar :: TestSVar a -> TestSequence a a #
getCurrentTime :: TestSequence a Int #
readNumber :: TestSequence a Int #
haveNumber :: Int -> TestSequence a () #
data TestSequenceEvents #
Constructors
| GetVar Word32 | |
| PutVar Word32 | |
| GetTime Word32 | |
| ReadNumber Int | |
| HaveNumber Int |
Instances
newtype TestSequenceState b #
Constructors
| TestSequenceState (Word32, [TestSequenceEvents], Maybe b) |
Instances
| Show (TestSequenceState ct) # | |
newtype TestSequence b a #
Constructors
| TestSequence (TestSequenceState b -> (TestSequenceState b, a)) |
Instances
| Monad (TestSequence a) # | |
| Functor (TestSequence a) # | |
| Applicative (TestSequence a) # | |