hscassandra 0.0.5 → 0.0.7
raw patch · 4 files changed
+72/−17 lines, 4 files
Files
- README +0/−0
- README.mkd +23/−0
- hscassandra.cabal +1/−1
- src/Database/Cassandra.hs +48/−16
− README
+ README.mkd view
@@ -0,0 +1,23 @@+#### Connecting+Connecting to cassandra is done with the withCassandra function, which takes a CassandraConfig instance, and a callback function.++ withCassandra initConfig{cassandraKeyspace="MyApplication"} (do+ getTime+ )+++#### Inserting +Inserts are done via the _insert_ function, taking A Column Family string name, a Key, and a a list of columns to add.++ insert "Users" "kirk@glyphsoftware.com" + [ "fn" =: "Kirk"+ , "ln" =: "Peterson"+ , "address" =| ["street" =: "2020 NE Going", "city"=:"Portland", "state" =: "OR"]+ , "gender" =: "M"+ ]++#### Retrieving+you can then pull the data back out via the _get_ function.++ get "Users" "kirk@glyphsoftware.com" AllColumns+
hscassandra.cabal view
@@ -1,5 +1,5 @@ name : hscassandra -version : 0.0.5+version : 0.0.7 license : BSD3 cabal-version : >= 1.6 author : Kirk Peterson
src/Database/Cassandra.hs view
@@ -1,8 +1,11 @@+{-# LANGUAGE RankNTypes #-}+ module Database.Cassandra ( Column(..) , (=:) , (=|) , insert+ , remove , Filter(..) , get , multiget@@ -43,11 +46,11 @@ | Super ColumnName [Column] deriving (Show) --- | Build up a column's insert values+-- Build up a column's insert values (=:) :: (BS column, BS value) => column -> value -> Column (=:) col val = Column (bs col) (bs val) --- | Build up a super column's insert values+-- Build up a super column's insert values (=|) :: (BS supercolumn) => supercolumn -> [Column] -> Column (=|) sup = Super (bs sup) @@ -61,7 +64,7 @@ insert column_family key columns = do consistency <- getConsistencyLevel conn <- getConnection- now <- getTime+ now <- getTime liftIO $ Cas.batch_mutate conn (Map.singleton (bs key) (Map.singleton column_family (mutations now))) consistency where mutations now = map (q now) columns@@ -71,8 +74,31 @@ col c v now = Thrift.Column (Just c) (Just v) (Just now) Nothing m now (Column c v) = col c v now +-- remove "Users" "necrobious@gmail.com" (columns ["fn", "address" , "ln"]) +remove :: (BS key) => ColumnFamily -> key -> Filter -> Cassandra ()+remove column_family key fltr = do + consistency <- getConsistencyLevel+ conn <- getConnection+ now <- getTime+ case fltr of+ AllColumns -> liftIO $ Cas.remove conn (bs key) (Thrift.ColumnPath (Just column_family) Nothing Nothing) now consistency+ ColNames [] -> liftIO $ Cas.remove conn (bs key) (Thrift.ColumnPath (Just column_family) Nothing Nothing) now consistency+ ColNames cs -> liftIO $ Cas.batch_mutate conn (Map.singleton (bs key) (Map.singleton column_family (mutations now Nothing cs))) consistency+ SupNames sc cs -> liftIO $ Cas.batch_mutate conn (Map.singleton (bs key) (Map.singleton column_family (mutations now (Just sc) cs))) consistency+ _ -> return ()+ where+ mutations now sup columns = [m now sup columns]+ m now sup cs = Thrift.Mutation Nothing (Just $ d now sup cs) + d now sup@(Just _) [] = Thrift.Deletion (Just now) sup Nothing -- delete the whole supercolumn + d now sup@(Just _) cs = Thrift.Deletion (Just now) sup (Just $ s cs) -- delete the supercolumn's columns by name + d now Nothing [] = Thrift.Deletion (Just now) Nothing Nothing -- delete ??? not sure what this will do + d now Nothing cs = Thrift.Deletion (Just now) Nothing (Just $ s cs) -- delete jsut the column names + s cs = Thrift.SlicePredicate (Just cs) Nothing++ data Filter = AllColumns | ColNames [ByteString]+ | SupNames ByteString [ByteString] | ColRange { rangeStart :: ByteString , rangeEnd :: ByteString@@ -80,35 +106,38 @@ , rangeLimit :: Int32 } -- | a smarter constructor for building a Range filter-range :: (BS column_name) => column_name -> column_name -> Bool -> Int32 -> Filter+range :: forall column_name. (BS column_name) => column_name -> column_name -> Bool -> Int32 -> Filter range start finish = ColRange (bs start) (bs finish) -- | a smarter constructor for building a Columns filter -columns :: (BS column_name) => [column_name] -> Filter+columns :: forall column_name. (BS column_name) => [column_name] -> Filter columns = ColNames . (map bs) +supercolumns :: forall column_name. (BS column_name) => column_name -> [column_name] -> Filter+supercolumns sc cs = SupNames (bs sc) (map bs cs)+ -- | for the given key, within the column family, retrieve all columns, unless filtered get :: (BS key) => ColumnFamily -> key -> Filter -> Cassandra [Column]-get column_family key filters = do+get column_family key fltr = do consistency <- getConsistencyLevel conn <- getConnection- results <- liftIO $ Cas.get_slice conn (bs key) (column_parent column_family) (slice_predicate filters) consistency + results <- liftIO $ Cas.get_slice conn (bs key) (column_parent column_family fltr) (slice_predicate fltr) consistency return $ foldr rewrap [] results get_count :: (BS key) => ColumnFamily -> key -> Filter -> Cassandra Int32-get_count column_family key filters = do+get_count column_family key fltr = do consistency <- getConsistencyLevel conn <- getConnection- liftIO $ Cas.get_count conn (bs key) (column_parent column_family) (slice_predicate filters) consistency + liftIO $ Cas.get_count conn (bs key) (column_parent column_family fltr) (slice_predicate fltr) consistency multiget :: (BS key) => ColumnFamily -> [key] -> Filter -> Cassandra (Map key [Column])-multiget column_family keys filters = do+multiget column_family keys fltr = do let byBs = keys2map keys consistency <- getConsistencyLevel conn <- getConnection- results <- liftIO $ Cas.multiget_slice conn (Map.keys byBs) (column_parent column_family) (slice_predicate filters) consistency - return $ map2map byBs $ Map.foldrWithKey remap Map.empty results -- $ foldr rewrap [] results+ results <- liftIO $ Cas.multiget_slice conn (Map.keys byBs) (column_parent column_family fltr) (slice_predicate fltr) consistency + return $ map2map byBs $ Map.foldrWithKey remap Map.empty results keys2map :: (BS key) => [key] -> Map ByteString key@@ -138,14 +167,17 @@ c2c _ acc = acc -column_parent :: ColumnFamily -> Thrift.ColumnParent-column_parent column_family = Thrift.ColumnParent (Just column_family) Nothing+column_parent :: ColumnFamily -> Filter -> Thrift.ColumnParent+column_parent column_family (SupNames sc _) = Thrift.ColumnParent (Just column_family) (Just sc) +column_parent column_family _ = Thrift.ColumnParent (Just column_family) Nothing + slice_predicate :: Filter -> Thrift.SlicePredicate slice_predicate AllColumns = Thrift.SlicePredicate Nothing (Just $ Thrift.SliceRange (Just Lazy.empty) (Just Lazy.empty) (Just False) (Just 100)) -slice_predicate (ColNames bs) = +slice_predicate (ColNames bs) = Thrift.SlicePredicate (Just bs) Nothing+slice_predicate (SupNames _ bs) = + Thrift.SlicePredicate (Just bs) Nothing slice_predicate (ColRange rs re rr rl) = Thrift.SlicePredicate Nothing (Just (Thrift.SliceRange (Just rs) (Just re) (Just rr) (Just rl)))-