Start compatibility layer

api.odocl

-Serializable_t
 Crypto_sigs
 Crypto
 ElGamal
+Serializable_t
+Serializable_compat_t
+Serializable_compat

src/lib.mllib

 StdExtra
 Core_datatypes_j
+Serializable_t
+Serializable_j
 Serializable_compat_t
 Serializable_compat_j
+Serializable_compat
 Common
 Crypto
 ElGamal

src/serializable_compat.atd

+<doc text="Serializable datatypes (compatibility layer)">
+
 (** {1 Core types} *)
 
 type number <ocaml predef from="Core_datatypes"> = abstract
@@ -72,7 +74,7 @@ type 'a election = {
 
 (** {1 Ballots} *)
 
-type 'a choice = {
+type 'a choice <ocaml predef from="Serializable" t="ciphertext"> = {
   alpha : 'a;
   beta : 'a;
 }

src/serializable_compat.ml

+open Serializable_compat_t
+
+let of_question q =
+  let {q_answers; q_min; q_max; q_question; _} = q in
+  let q_max = match q_max with
+    | Some i -> i
+    | None -> Array.length q_answers
+  in
+  let open Serializable_t in
+  {q_answers; q_min; q_max; q_question}
+
+let of_election e =
+  let {
+    e_description; e_name; e_public_key;
+    e_questions; e_uuid; e_short_name;
+    _
+  } = e in
+  let e_public_key = e_public_key.y in
+  let e_questions = Array.map of_question e_questions in
+  let open Serializable_t in
+  {
+    e_description; e_name; e_public_key;
+    e_questions; e_uuid; e_short_name
+  }
+
+let of_proof p =
+  let {dp_challenge; dp_response; _} = p in
+  let open Serializable_t in
+  {challenge = dp_challenge; response = dp_response}
+
+let of_proofs ps = Array.map of_proof ps
+
+let of_answer a =
+  let {choices; individual_proofs; overall_proof} = a in
+  let individual_proofs = Array.map of_proofs individual_proofs in
+  let overall_proof = of_proofs overall_proof in
+  let open Serializable_t in
+  {choices; individual_proofs; overall_proof}
+
+let of_ballot b =
+  let {answers; election_hash; election_uuid} = b in
+  let answers = Array.map of_answer answers in
+  let open Serializable_t in
+  {answers; election_hash; election_uuid}

src/serializable_compat.mli

+(** Compatibility layer with the Helios reference implementation *)
+
+open Serializable_compat_t
+
+val of_election : 'a election -> 'a Serializable_t.election
+val of_ballot : 'a ballot -> 'a Serializable_t.ballot