Changes to use Reader monad

pull/1/head
Abhinav Sarkar 2015-12-15 11:59:53 +05:30
parent b7d13c4947
commit 3d00a89062
3 changed files with 72 additions and 49 deletions

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@ -19,6 +19,7 @@ library
build-depends: base >= 4.7 && < 5
, text
, containers
, mtl
default-extensions: OverloadedStrings, RecordWildCards, ScopedTypeVariables,
BangPatterns, TupleSections, NamedFieldPuns, GeneralizedNewtypeDeriving,
DeriveDataTypeable

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@ -6,15 +6,10 @@ import Ringo.Types
import qualified Data.Map as Map
import qualified Data.Text as Text
import Control.Monad.Reader (Reader, asks)
import Data.Maybe (mapMaybe, fromMaybe, fromJust)
import Data.Monoid ((<>))
import Data.List (nub, find)
import Data.Text (Text)
data ValidationError = MissingTable TableName
| MissingFact TableName
| MissingColumn TableName ColumnName
deriving (Eq, Show)
findTable :: TableName -> [Table] -> Maybe Table
findTable tName = find ((== tName) . tableName)
@ -30,12 +25,14 @@ checkTableForCol tab colName =
[ MissingColumn (tableName tab) colName |
not . any ((colName ==) . columnName) . tableColumns $ tab ]
validateTable :: [Table] -> Table -> [ValidationError]
validateTable tables table = concatMap checkConstraint . tableConstraints $ table
validateTable :: Table -> Reader Env [ValidationError]
validateTable table = do
tables <- asks envTables
return . concatMap (checkConstraint tables) . tableConstraints $ table
where
checkConstraint (PrimaryKey colName) = checkTableForCol table colName
checkConstraint (UniqueKey columnNames) = checkTableForColRefs table columnNames
checkConstraint (ForeignKey oTableName columnNames) =
checkConstraint _ (PrimaryKey colName) = checkTableForCol table colName
checkConstraint _ (UniqueKey columnNames) = checkTableForColRefs table columnNames
checkConstraint tables (ForeignKey oTableName columnNames) =
case findTable oTableName tables of
Just oTable -> checkTableForColRefs table (map fst columnNames)
++ checkTableForColRefs oTable (map snd columnNames)
@ -43,35 +40,45 @@ validateTable tables table = concatMap checkConstraint . tableConstraints $ tabl
checkTableForColRefs tab = concatMap (checkTableForCol tab)
validateFact :: [Table] -> [Fact] -> Fact -> [ValidationError]
validateFact tables facts Fact {..} =
validateFact :: Fact -> Reader Env [ValidationError]
validateFact Fact {..} = do
tables <- asks envTables
case findTable factTableName tables of
Nothing -> [ MissingTable factTableName ]
Just table -> validateTable tables table
++ concatMap checkFactParents factParentNames
++ concatMap (checkColumn table) factColumns
Nothing -> return [ MissingTable factTableName ]
Just table -> do
tableVs <- validateTable table
parentVs <- concat <$> mapM checkFactParents factParentNames
let colVs = concatMap (checkColumn table) factColumns
return $ tableVs ++ parentVs ++ colVs
where
checkFactParents fName = case findFact fName facts of
Nothing -> [ MissingFact fName ]
Just pFact -> validateFact tables facts pFact
checkFactParents fName = do
facts <- asks envFacts
case findFact fName facts of
Nothing -> return [ MissingFact fName ]
Just pFact -> validateFact pFact
checkColumn table = maybe [] (checkTableForCol table) . factColumnName
withFactValidation :: [Table] -> [Fact] -> Fact -> (Table -> a) -> Either [ValidationError] a
withFactValidation tables facts fact func =
let errors = validateFact tables facts fact
in if not $ null errors
then Left errors
else Right . func . fromJust $ findTable (factTableName fact) tables
withFactValidation :: Fact -> (Table -> Reader Env a) -> Reader Env (Either [ValidationError] a)
withFactValidation fact func = do
tables <- asks envTables
errors <- validateFact fact
if not $ null errors
then return $ Left errors
else fmap Right . func . fromJust . findTable (factTableName fact) $ tables
extractDimensions' :: [Table] -> Text -> Fact -> Table -> [Table]
extractDimensions' tables prefix fact Table {..} = dimsFromIds ++ dimsFromVals
extractDimensions' :: Fact -> Table -> Reader Env [Table]
extractDimensions' fact Table {..} = do
tables <- asks envTables
prefix <- settingDimPrefix <$> asks envSettings
return $ dimsFromIds tables ++ dimsFromVals prefix
where
dimsFromIds =
dimsFromIds tables =
flip mapMaybe (factColumns fact) $ \fcol -> case fcol of
DimId d _ -> findTable d tables
_ -> Nothing
dimsFromVals =
dimsFromVals prefix =
map (\(dim, cols) -> Table { tableName = prefix <> dim
, tableColumns = Column "id" "serial" NotNull : cols
, tableConstraints = [ PrimaryKey "id"
@ -92,28 +99,33 @@ extractDimensions' tables prefix fact Table {..} = dimsFromIds ++ dimsFromVals
cleanColumn dim col@Column {..} =
col { columnName = fromMaybe columnName . Text.stripPrefix (dim <> "_") $ columnName }
extractDimensions :: [Table] -> [Fact] -> Text -> Fact -> Either [ValidationError] [Table]
extractDimensions tables facts prefix fact =
withFactValidation tables facts fact $ extractDimensions' tables prefix fact
extractDimensions :: Fact -> Reader Env (Either [ValidationError] [Table])
extractDimensions fact = withFactValidation fact $ extractDimensions' fact
extractAllDimensions' :: [Table] -> [Fact] -> Text -> Fact -> Table -> [Table]
extractAllDimensions' tables facts dimPrefix fact table =
nub $ extractDimensions' tables dimPrefix fact table ++ concatMap extract (factParentNames fact)
extractAllDimensions' :: Fact -> Table -> Reader Env [Table]
extractAllDimensions' fact table = do
myDims <- extractDimensions' fact table
parentDims <- concat <$> mapM extract (factParentNames fact)
return . nub $ myDims ++ parentDims
where
extract fName =
extract fName = do
tables <- asks envTables
facts <- asks envFacts
let pFact = fromJust . findFact fName $ facts
pFactTable = fromJust . findTable (factTableName pFact) $ tables
in extractAllDimensions' tables facts dimPrefix pFact pFactTable
extractAllDimensions' pFact pFactTable
extractFactTable :: Fact -> Reader Env (Either [ValidationError] Table)
extractFactTable fact =
withFactValidation fact $ \table -> do
Settings {..} <- asks envSettings
allDims <- extractAllDimensions' fact table
extractFactTable :: [Table] -> [Fact] -> Settings -> Fact -> Either [ValidationError] Table
extractFactTable tables facts Settings {..} fact =
withFactValidation tables facts fact $ \table ->
let intType = "integer"
allDims = extractAllDimensions' tables facts settingDimPrefix fact table
sourceColumnType colName = columnType . fromJust . findColumn colName . tableColumns $ table
columns = flip concatMap (factColumns fact) $ \col -> case col of
DimTime cName -> [ Column (timeUnitColName cName) intType NotNull ]
DimTime cName -> [ Column (timeUnitColName cName settingTimeUnit) intType NotNull ]
NoDimId cName -> [ fromJust . findColumn cName . tableColumns $ table]
FactCount cName -> [ Column cName intType NotNull ]
FactSum scName cName -> [ Column cName (sourceColumnType scName) NotNull ]
@ -131,13 +143,13 @@ extractFactTable tables facts Settings {..} fact =
ukColNames =
(++ map (columnName . fst) fks)
. flip mapMaybe (factColumns fact) $ \col -> case col of
DimTime cName -> Just (timeUnitColName cName)
DimTime cName -> Just (timeUnitColName cName settingTimeUnit)
NoDimId cName -> Just cName
_ -> Nothing
in Table { tableName = settingFactPrefix <> factName fact
, tableColumns = columns ++ map fst fks
, tableConstraints = UniqueKey ukColNames : map snd fks
}
return Table { tableName = settingFactPrefix <> factName fact
, tableColumns = columns ++ map fst fks
, tableConstraints = UniqueKey ukColNames : map snd fks
}
where
timeUnitColName colName = colName <> "_" <> timeUnitName settingTimeUnit <> "_id"
timeUnitColName colName timeUnit = colName <> "_" <> timeUnitName timeUnit <> "_id"

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@ -73,3 +73,13 @@ defSettings = Settings
, settingFactPrefix = "fact_"
, settingTimeUnit = Minute
}
data ValidationError = MissingTable TableName
| MissingFact TableName
| MissingColumn TableName ColumnName
deriving (Eq, Show)
data Env = Env { envTables :: [Table]
, envFacts :: [Fact]
, envSettings :: Settings
} deriving (Eq, Show)