use cereal for efficient serialization for wire format

I tried both binary and cereal. For a ActivityMessage that takes 341
bytes in JSON and has a dataSize of 129, both used 165 bytes. Went with
cereal since lazy bytestrings are not needed, and I might want to use
https://hackage.haskell.org/package/safecopy later.

(Perhaps I should be using protocol buffers or something to make it
easier for non-haskell implementations? But that would complicate things
a lot.)

1 files changed, 15 insertions, 0 deletions

diff --git a/Serialization.hs b/Serialization.hs
new file mode 100644
index 0000000..6940550
--- /dev/null
+++ b/Serialization.hs
@@ -0,0 +1,15 @@
+module Serialization (
+	module Data.Aeson,
+	Serialize,
+	Generic,
+	sumOptions
+) where
+
+import GHC.Generics (Generic)
+import Data.Serialize
+import Data.Aeson
+import qualified Data.Aeson.Types as Aeson
+
+-- | Nicer JSON encoding for sum types.
+sumOptions :: Aeson.Options
+sumOptions = defaultOptions { Aeson.sumEncoding = Aeson.ObjectWithSingleField }