v2.3.0: save and restore messages when the server is restarted (#395)

* save and restore messages when server is restarted

* read file line by line

* add import

* optmize restoring messages by reading the whole file

* update version to 2.3.0

* update scripts

* add script

* update readme

src/Simplex/Messaging/Encoding/String.hs

@@ -26,9 +26,11 @@ import qualified Data.ByteString.Base64.URL as U
 import Data.ByteString.Char8 (ByteString)
 import qualified Data.ByteString.Char8 as B
 import Data.Char (isAlphaNum)
+import Data.Int (Int64)
 import qualified Data.List.NonEmpty as L
 import Data.Text (Text)
 import Data.Text.Encoding (decodeLatin1, encodeUtf8)
+import Data.Time.Clock.System (SystemTime (..))
 import Data.Word (Word16)
 import Simplex.Messaging.Parsers (parseAll)
 import Simplex.Messaging.Util ((<$?>))
@@ -82,6 +84,14 @@ instance StrEncoding Word16 where
   strEncode = B.pack . show
   strP = A.decimal
 
+instance StrEncoding Int64 where
+  strEncode = B.pack . show
+  strP = A.decimal
+
+instance StrEncoding SystemTime where
+  strEncode = strEncode . systemSeconds
+  strP = MkSystemTime <$> strP <*> pure 0
+
 -- lists encode/parse as comma-separated strings
 strEncodeList :: StrEncoding a => [a] -> ByteString
 strEncodeList = B.intercalate "," . map strEncode