+{-# LANGUAGE
+ ExistentialQuantification,
+ FlexibleContexts,
+ FlexibleInstances,
+ MultiParamTypeClasses,
+ OverlappingInstances,
+ TypeFamilies,
+ UndecidableInstances
+ #-}
+{-# LANGUAGE QuasiQuotes #-} -- DELETE THIS
module Database.RRDtool.Create
( DataSource
, ExternalDSType(..)
, createRRD
-- Data.HList
- , (.*.)
- , HNil(..)
+ , (.&.)
+ , Nil(..)
-- Database.RRDtool.Expression
, Constant(..)
where
import Data.HList
+import Data.HList.Graph
import Data.Time.Clock
import Data.Time.Clock.POSIX
import Database.RRDtool.Expression
+import Types.Data.Bool
-- |A single RRD can accept input from several data sources (DS), for
-- 32bit counter, DERIVE with @'dsMin' = 0@ is probably preferable. If
-- you are using a 64bit counter, just about any max setting will
-- eliminate the possibility of mistaking a reset for a counter wrap.
-class DataSource ds
+class DataSource ds where
+ type DSName ds
data ExternalDSType
= GAUGE -- ^GAUGE is for things like temperatures or number of
-- number of messages since the last update.
deriving (Show, Eq, Ord)
-instance DataSource ExternalDSType
-
-data ExternalDataSource
+data ExternalDataSource vn
= ExternalDataSource {
-- |The name you will use to reference this particular data
-- source from an RRD. A ds name must be 1 to 19 characters
-- long in the characters @[a-zA-Z0-9_]@.
- edsName :: !String
+ edsName :: !vn
-- |The type of this data source.
, edsType :: !ExternalDSType
-- |Defines the maximum number of seconds that may pass
}
deriving (Show, Eq, Ord)
+instance ( IsVarName vn ~ True
+ )
+ => DataSource (ExternalDataSource vn)
+ where
+ type DSName (ExternalDataSource vn) = vn
+
+type instance MentionedVars (ExternalDataSource vn) = Nil
-- |ComputedDataSource is for storing the result of a formula applied
-- to other data sources in the RRD. This data source is not supplied
-- \"computed\" columns.
--
-- FIXME: doc links
-data ComputedDataSource e
+data ComputedDataSource vn e
= ComputedDataSource {
-- |See 'edsName'
- cdsName :: !String
+ cdsName :: !vn
-- |rpn-expression defines the formula used to compute the
-- PDPs of a COMPUTE data source from other data sources in
-- the same \<RRD\>. It is similar to defining a CDEF argument
}
deriving (Show, Eq, Ord)
-instance IsCommonExpr e => DataSource (ComputedDataSource e)
+instance ( IsVarName vn ~ True
+ , IsCommonExpr e ~ True
+ )
+ => DataSource (ComputedDataSource vn e)
+ where
+ type DSName (ComputedDataSource vn e) = vn
+type instance MentionedVars (ComputedDataSource vn e) = MentionedVars e
+{-
dsTest = ComputedDataSource {
cdsName = "foo"
--- , dsExpr = Previous :<: Const 100
--- , dsExpr = Var "foo" :<: Const 100
- , cdsExpr = AverageOf (Const 100 .*. Const 200 .*. HNil)
+-- , cdsExpr = Previous :<: Const 100
+-- , cdsExpr = Var "foo" :<: Const 100
+ , cdsExpr = AverageOf (Const 100 .*. Const 200 .*. Nil)
}
+-}
+
+-- |The name of the RRD you want to create. RRD files should end with
+-- the extension @.rrd@. However, RRDtool will accept any filename.
+newtype RRDPath = RRDPath FilePath
+
+-- |Do not clobber an existing file of the same name.
+data KeepOldRRD = KeepOldRRD
+
+-- |Specifies the time in seconds since @1970-01-01 UTC@ when the
+-- first value should be added to the RRD. RRDtool will not accept any
+-- data timed before or at the time specified. (default: @now - 10s@)
+newtype RRDStartTime = RRDStartTime POSIXTime
+
+-- |Specifies the base interval in seconds with which data will be fed
+-- into the RRD. (default: 300 sec)
+newtype RRDInterval = RRDInterval NominalDiffTime
+
+class RRDSpec s
+instance ( Occurs RRDPath s
+ , OccursOpt KeepOldRRD s
+ , OccursOpt RRDStartTime s
+ , OccursOpt RRDInterval s
+ , Occurs RRDDataSources s
+ )
+ => RRDSpec s
+
+class NonEmptyDSList l
+instance ( DSList l
+ , DataSource d
+ )
+ => NonEmptyDSList (Cons d l)
+
+class DSList l
+instance DSList Nil
+instance ( DSList l
+ , DataSource d
+ )
+ => DSList (Cons d l)
+
+data RRDDataSources
+ = forall l.
+ ( NonEmptyDSList l
+ , Graph l -- FIXME: this constraint is too weak
+ )
+ => RRDDataSources l
+
+-- RRDDataSources is a graph.
+instance ( DSList g
+ , NodeSet g
+ , NoDuplicates (Map NodeIDA g)
+ )
+ => Graph g
+ where
+ type Empty g = Nil
+ type Nodes g = g
+
+type instance IsEmpty Nil = True
+type instance IsEmpty (Cons e l) = False
+
+instance ( NodeIDSet (MentionedVars d)
+ , DataSource d
+ )
+ => Node d
+ where
+ type NodeID d = DSName d
+ type LinksFrom d = MentionedVars d
-- |The 'createRRD' function lets you set up new Round Robin Database
-- (RRD) files. The file is created at its final, full size and filled
-- with @*UNKNOWN*@ data.
-createRRD
- :: FilePath -- ^The name of the RRD you want to create. RRD files
- -- should end with the extension @.rrd@. However,
- -- RRDtool will accept any filename.
- -> Bool -- ^Do not clobber an existing file of the same name.
- -> Maybe POSIXTime -- ^Specifies the time in seconds since
- -- @1970-01-01 UTC@ when the first value should
- -- be added to the RRD. RRDtool will not accept
- -- any data timed before or at the time
- -- specified. (default: @now - 10s@)
- -> Maybe NominalDiffTime -- ^Specifies the base interval in
- -- seconds with which data will be fed
- -- into the RRD. (default: 300 sec)
--- -> [DataSource] -- ^Data sources to accept input from.
- -> IO ()
+createRRD :: ( RRDSpec s
+ )
+ => s -> IO ()
createRRD = error "FIXME"
+
+testMain :: IO ()
+testMain = let s = RRDPath "test.rrd" .&.
+ KeepOldRRD .&.
+ RRDDataSources testDSList .&.
+ Nil
+ in
+ createRRD s
+
+testDSList = let a = ComputedDataSource {
+ cdsName = [$hString|foo|]
+ , cdsExpr = Var [$hString|bar|]
+ }
+ b = ComputedDataSource {
+ cdsName = [$hString|bar|]
+ , cdsExpr = Var [$hString|foo|] -- shouldn't typecheck!
+ }
+ c = ComputedDataSource {
+ cdsName = [$hString|baz|]
+ , cdsExpr = Var [$hString|foo|] -- should typecheck!
+ }
+ in a .&. b .&. Nil
\ No newline at end of file
projects / hs-rrdtool.git / blobdiff