Add serialization/deseriation support to event log

See bincode and serde_json for usage:
https://github.com/TyOverby/bincode

Fixes #1

Cargo.toml

@@ -26,4 +26,6 @@ asm = ["sha2-asm"]
 rayon = "1.0.0"
 sha2 = "0.7.0"
 sha2-asm = {version="0.3", optional=true}
-digest = "0.7.2"
+generic-array = { version = "0.9.0", default-features = false, features = ["serde"] }
+serde = "1.0.27"
+serde_derive = "1.0.27"

src/lib.rs

@@ -1,6 +1,9 @@
 #![cfg_attr(feature = "unstable", feature(test))]
 pub mod log;
 pub mod historian;
-extern crate digest;
+extern crate generic_array;
 extern crate rayon;
+extern crate serde;
+#[macro_use]
+extern crate serde_derive;
 extern crate sha2;

src/log.rs

@@ -13,11 +13,11 @@
 /// fastest processor. Duration should therefore be estimated by assuming that the hash
 /// was generated by the fastest processor at the time the entry was logged.
 
-use digest::generic_array::GenericArray;
-use digest::generic_array::typenum::U32;
+use generic_array::GenericArray;
+use generic_array::typenum::U32;
 pub type Sha256Hash = GenericArray<u8, U32>;
 
-#[derive(Debug, PartialEq, Eq, Clone)]
+#[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Clone)]
 pub struct Entry {
     pub num_hashes: u64,
     pub end_hash: Sha256Hash,
@@ -29,7 +29,7 @@ pub struct Entry {
 /// be generated in 'num_hashes' hashes and verified in 'num_hashes' hashes.  By logging
 /// a hash alongside the tick, each tick and be verified in parallel using the 'end_hash'
 /// of the preceding tick to seed its hashing.
-#[derive(Debug, PartialEq, Eq, Clone)]
+#[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Clone)]
 pub enum Event {
     Tick,
     UserDataKey(Sha256Hash),