X-Git-Url: http://git.cielonegro.org/gitweb.cgi?a=blobdiff_plain;f=Database%2FRRDtool%2FCreate.hs;h=5dd3b9f8fc12aadee9c64bef068dd335ee99b289;hb=2787678974b80d73e91b49b6b7c5469c6eb5ac1e;hp=e0146c0170035054ba447e57799dac9e47e09867;hpb=5cab7a6846cf5ad61df14def9c0e023840bb756b;p=hs-rrdtool.git diff --git a/Database/RRDtool/Create.hs b/Database/RRDtool/Create.hs index e0146c0..5dd3b9f 100644 --- a/Database/RRDtool/Create.hs +++ b/Database/RRDtool/Create.hs @@ -1,14 +1,23 @@ +{-# LANGUAGE + FlexibleContexts, + FlexibleInstances, + TypeFamilies, + UndecidableInstances + #-} module Database.RRDtool.Create - ( DataSource(..) + ( DataSource + , ExternalDSType(..) + , ExternalDataSource(..) + , ComputedDataSource(..) , createRRD -- Data.HList - , (.*.) + , (.&.) , HNil(..) -- Database.RRDtool.Expression , Constant(..) - , IsVarName(..) + , IsVarName , Variable(..) , CommonUnaryOp(..) , CommonBinaryOp(..) @@ -25,6 +34,7 @@ import Data.HList 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 @@ -51,24 +61,56 @@ import Database.RRDtool.Expression -- 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. -data DataSource - = -- |GAUGE is for things like temperatures or number of people in - -- a room or the value of a RedHat share. - GAUGE { +class DataSource ds + +data ExternalDSType + = GAUGE -- ^GAUGE is for things like temperatures or number of + -- people in a room or the value of a RedHat share. + | COUNTER -- ^COUNTER is for continuous incrementing counters + -- like the ifInOctets counter in a router. The COUNTER + -- data source assumes that the counter never + -- decreases, except when a counter overflows. The + -- update function takes the overflow into account. The + -- counter is stored as a per-second rate. When the + -- counter overflows, RRDtool checks if the overflow + -- happened at the 32bit or 64bit border and acts + -- accordingly by adding an appropriate value to the + -- result. + | DERIVE -- ^DERIVE will store the derivative of the line going + -- from the last to the current value of the data + -- source. This can be useful for gauges, for example, + -- to measure the rate of people entering or leaving a + -- room. Internally, derive works exactly like COUNTER + -- but without overflow checks. So if your counter does + -- not reset at 32 or 64 bit you might want to use + -- DERIVE and combine it with a 'dsMin' value of 0. + | ABSOLUTE -- ^ABSOLUTE is for counters which get reset upon + -- reading. This is used for fast counters which tend + -- to overflow. So instead of reading them normally you + -- reset them after every read to make sure you have a + -- maximum time available before the next + -- overflow. Another usage is for things you count like + -- number of messages since the last update. + deriving (Show, Eq, Ord) + +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 + -- source from an RRD. A ds name must be 1 to 19 characters -- long in the characters @[a-zA-Z0-9_]@. - dsName :: !String - -- |Defines the maximum number of seconds that may - -- pass between two updates of this data source before the - -- value of the data source is assumed to be @*UNKNOWN*@. - , dsHeartbeat :: !NominalDiffTime - -- |'dsMin' and 'dsMax' Define the expected range values for - -- data supplied by a data source. If 'dsMin' and\/or 'dsMax' + edsName :: !vn + -- |The type of this data source. + , edsType :: !ExternalDSType + -- |Defines the maximum number of seconds that may pass + -- between two updates of this data source before the value of + -- the data source is assumed to be @*UNKNOWN*@. + , edsHeartbeat :: !NominalDiffTime + -- |'edsMin' and 'edsMax' Define the expected range values for + -- data supplied by a data source. If 'edsMin' and\/or 'edsMax' -- any value outside the defined range will be regarded as - -- @*UNKNOWN*@. If you do not know or care about 'dsMin' and - -- 'dsMax', set them to 'Nothing' for unknown. Note that - -- 'dsMin' and 'dsMax' always refer to the processed values of + -- @*UNKNOWN*@. If you do not know or care about 'edsMin' and + -- 'edsMax', set them to 'Nothing' for unknown. Note that + -- 'edsMin' and 'edsMax' always refer to the processed values of -- the DS. For a traffic-'COUNTER' type DS this would be the -- maximum and minimum data-rate expected from the device. -- @@ -76,62 +118,32 @@ data DataSource -- available, always set the min and\/or max properties. This -- will help RRDtool in doing a simple sanity check on the -- data supplied when running update. - , dsMin :: !(Maybe Double) - -- |See 'dsMin'. - , dsMax :: !(Maybe Double) - } - -- |COUNTER is for continuous incrementing counters like the - -- ifInOctets counter in a router. The COUNTER data source assumes - -- that the counter never decreases, except when a counter - -- overflows. The update function takes the overflow into - -- account. The counter is stored as a per-second rate. When the - -- counter overflows, RRDtool checks if the overflow happened at - -- the 32bit or 64bit border and acts accordingly by adding an - -- appropriate value to the result. - | COUNTER { - dsName :: !String - , dsHeartbeat :: !NominalDiffTime - , dsMin :: !(Maybe Double) - , dsMax :: !(Maybe Double) - } - -- |DERIVE will store the derivative of the line going from the - -- last to the current value of the data source. This can be - -- useful for gauges, for example, to measure the rate of people - -- entering or leaving a room. Internally, derive works exactly - -- like COUNTER but without overflow checks. So if your counter - -- does not reset at 32 or 64 bit you might want to use DERIVE and - -- combine it with a 'dsMin' value of 0. - | DERIVE { - dsName :: !String - , dsHeartbeat :: !NominalDiffTime - , dsMin :: !(Maybe Double) - , dsMax :: !(Maybe Double) - } - -- |ABSOLUTE is for counters which get reset upon reading. This is - -- used for fast counters which tend to overflow. So instead of - -- reading them normally you reset them after every read to make - -- sure you have a maximum time available before the next - -- overflow. Another usage is for things you count like number of - -- messages since the last update. - | ABSOLUTE { - dsName :: !String - , dsHeartbeat :: !NominalDiffTime - , dsMin :: !(Maybe Double) - , dsMax :: !(Maybe Double) - } - -- |COMPUTE is for storing the result of a formula applied to - -- other data sources in the RRD. This data source is not supplied - -- a value on update, but rather its Primary Data Points (PDPs) - -- are computed from the PDPs of the data sources according to the - -- rpn-expression that defines the formula. Consolidation - -- functions are then applied normally to the PDPs of the COMPUTE - -- data source (that is the rpn-expression is only applied to - -- generate PDPs). In database software, such data sets are - -- referred to as \"virtual\" or \"computed\" columns. - -- - -- FIXME: doc links - | forall a. IsCommonExpr a => COMPUTE { - dsName :: !String + , edsMin :: !(Maybe Double) + -- |See 'edsMin'. + , edsMax :: !(Maybe Double) + } + deriving (Show, Eq, Ord) + +instance ( IsVarName vn ~ True + ) + => DataSource (ExternalDataSource vn) + + +-- |ComputedDataSource is for storing the result of a formula applied +-- to other data sources in the RRD. This data source is not supplied +-- a value on update, but rather its Primary Data Points (PDPs) are +-- computed from the PDPs of the data sources according to the +-- rpn-expression that defines the formula. Consolidation functions +-- are then applied normally to the PDPs of the COMPUTE data source +-- (that is the rpn-expression is only applied to generate PDPs). In +-- database software, such data sets are referred to as \"virtual\" or +-- \"computed\" columns. +-- +-- FIXME: doc links +data ComputedDataSource vn e + = ComputedDataSource { + -- |See 'edsName' + cdsName :: !vn -- |rpn-expression defines the formula used to compute the -- PDPs of a COMPUTE data source from other data sources in -- the same \. It is similar to defining a CDEF argument @@ -145,33 +157,57 @@ data DataSource -- graph command. -- -- FIXME: doc links - , dsExpr :: !a + , cdsExpr :: !e } + deriving (Show, Eq, Ord) + +instance ( IsVarName vn ~ True + , IsCommonExpr e ~ True + ) + => DataSource (ComputedDataSource vn e) -dsTest :: DataSource -dsTest = COMPUTE { - dsName = "foo" --- , dsExpr = Previous :<: Const 100 --- , dsExpr = Var "foo" :<: Const 100 - , dsExpr = AverageOf (Const 100 .*. Const 200 .*. HNil) +{- +dsTest = ComputedDataSource { + cdsName = "foo" +-- , cdsExpr = Previous :<: Const 100 +-- , cdsExpr = Var "foo" :<: Const 100 + , cdsExpr = AverageOf (Const 100 .*. Const 200 .*. HNil) } +-} + +-- |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 ( HOccurs RRDPath s + , HOccursOpt KeepOldRRD s + , HOccursOpt RRDStartTime s + , HOccursOpt RRDInterval s + ) + => RRDSpec s -- |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 .&. + HNil + in + createRRD s