Merge pull request #207 from haskell-servant/jkarni/cassava

Add servant-cassava.

servant-cassava/LICENSE

@@ -0,0 +1,30 @@
+Copyright (c) 2015, Julian K. Arni
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Julian K. Arni nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

servant-cassava/Setup.hs

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+import Distribution.Simple
+main = defaultMain

servant-cassava/servant-cassava.cabal

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+-- Initial servant-cassava.cabal generated by cabal init.  For further
+-- documentation, see http://haskell.org/cabal/users-guide/
+
+name:                servant-cassava
+version:             0.4.4.2
+synopsis:            Servant CSV content-type for cassava
+-- description:
+homepage:            http://haskell-servant.github.io/
+license:             BSD3
+license-file:        LICENSE
+author:              Julian K. Arni
+maintainer:          jkarni@gmail.com
+-- copyright:
+-- category:
+build-type:          Simple
+-- extra-source-files:
+cabal-version:       >=1.10
+
+library
+  exposed-modules:     Servant.CSV.Cassava
+  -- other-modules:
+  -- other-extensions:
+  build-depends:       base >=4.6 && <5
+                     , cassava >0.4 && <0.5
+                     , servant ==0.5.*
+                     , http-media
+                     , vector
+  hs-source-dirs:      src
+  default-language:    Haskell2010

servant-cassava/src/Servant/CSV/Cassava.hs

@@ -0,0 +1,88 @@
+{-# LANGUAGE DeriveDataTypeable    #-}
+{-# LANGUAGE DeriveGeneric         #-}
+{-# LANGUAGE FlexibleInstances     #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE OverloadedStrings     #-}
+{-# LANGUAGE ScopedTypeVariables   #-}
+
+-- | A @CSV@ empty datatype with `MimeRender` and `MimeUnrender` instances for
+-- @cassava@'s encoding and decoding classes.
+--
+-- >>> type Eg = Get '[(CSV', MyEncodeOptions)] [(Int, String)]
+--
+-- Default encoding and decoding options are also provided, along with the
+-- @CSV@ type synonym that uses them.
+--
+-- >>> type EgDefault = Get '[CSV] [(Int, String)]
+module Servant.CSV.Cassava where
+
+import           Data.Csv
+import           Data.Proxy         (Proxy (..))
+import           Data.Typeable      (Typeable)
+import           Data.Vector        (Vector)
+import           GHC.Generics       (Generic)
+import qualified Network.HTTP.Media as M
+import           Servant.API        (Accept (..), MimeRender (..),
+                                     MimeUnrender (..))
+
+data CSV' deriving (Typeable, Generic)
+
+type CSV = (CSV', DefaultDecodeOpts)
+
+-- | @text/csv;charset=utf-8@
+instance Accept (CSV', a) where
+    contentType _ = "text" M.// "csv" M./: ("charset", "utf-8")
+
+-- * Encoding
+
+-- ** Instances
+
+-- | Encode with 'encodeByNameWith'. The 'Header' param is used for determining
+-- the order of headers and fields.
+instance ( ToNamedRecord a, EncodeOpts opt
+         ) => MimeRender (CSV', opt) (Header, [a]) where
+    mimeRender _ (hdr, vals) = encodeByNameWith (encodeOpts p) hdr vals
+      where p = Proxy :: Proxy opt
+
+-- | Encode with 'encodeDefaultOrderedByNameWith'
+instance ( DefaultOrdered a, ToNamedRecord a, EncodeOpts opt
+         ) => MimeRender (CSV', opt) [a] where
+    mimeRender _ = encodeDefaultOrderedByNameWith (encodeOpts p)
+      where p = Proxy :: Proxy opt
+
+
+-- ** Encode Options
+
+class EncodeOpts a where
+    encodeOpts :: Proxy a -> EncodeOptions
+
+data DefaultEncodeOpts deriving (Typeable, Generic)
+
+instance EncodeOpts DefaultEncodeOpts where
+    encodeOpts _ = defaultEncodeOptions
+
+-- * Decoding
+
+-- ** Instances
+
+-- | Decode with 'decodeByNameWith'
+instance ( FromNamedRecord a, DecodeOpts opt
+         ) => MimeUnrender (CSV', opt) (Header, Vector a) where
+    mimeUnrender _ = decodeByNameWith (decodeOpts p)
+      where p = Proxy :: Proxy opt
+
+-- | Decode with 'decodeWith'. Assumes data has headers, which are stripped.
+instance ( FromRecord a, DecodeOpts opt
+         ) => MimeUnrender (CSV', opt) (Vector a) where
+    mimeUnrender _ = decodeWith (decodeOpts p) HasHeader
+      where p = Proxy :: Proxy opt
+
+-- ** Decode Options
+
+class DecodeOpts a where
+    decodeOpts :: Proxy a -> DecodeOptions
+
+data DefaultDecodeOpts deriving (Typeable, Generic)
+
+instance DecodeOpts DefaultDecodeOpts where
+    decodeOpts _ = defaultDecodeOptions

sources.txt

@@ -1,4 +1,5 @@
 servant
+servant-cassava
 servant-client
 servant-docs
 servant-js

stack.yaml

@@ -4,6 +4,7 @@ flags:
 packages:
 - servant/
 - servant-blaze/
+- servant-cassava/
 - servant-client/
 - servant-docs/
 - servant-examples/