Implement generic serialization/deserialization (#260)

* complete general serialization

* bump default params temporarily

* disable recursion in great_boy_pod example

src/backends/plonky2/mod.rs

@@ -10,11 +10,13 @@ pub mod signedpod;
 
 use std::sync::LazyLock;
 
+use base64::{prelude::BASE64_STANDARD, Engine};
 pub use error::*;
+use plonky2::util::serialization::{Buffer, Read};
 
 use crate::{
     backends::plonky2::{
-        basetypes::CircuitData,
+        basetypes::{CircuitData, CommonCircuitData, Proof},
         circuits::mainpod::{MainPodVerifyTarget, NUM_PUBLIC_INPUTS},
         recursion::RecursiveCircuit,
     },
@@ -37,3 +39,36 @@ pub static STANDARD_REC_MAIN_POD_CIRCUIT_DATA: LazyLock<CircuitData> = LazyLock:
         .1
     )
 });
+
+pub fn serialize_bytes(bytes: &[u8]) -> String {
+    BASE64_STANDARD.encode(bytes)
+}
+
+pub fn deserialize_bytes(data: &str) -> Result<Vec<u8>> {
+    BASE64_STANDARD.decode(data).map_err(|e| {
+        Error::custom(format!(
+            "Failed to decode data from base64: {}. Value: {}",
+            e, data
+        ))
+    })
+}
+
+pub fn deserialize_proof(common: &CommonCircuitData, proof: &str) -> Result<Proof> {
+    let decoded = deserialize_bytes(proof)?;
+    let mut buf = Buffer::new(&decoded);
+    let proof = buf.read_proof(common).map_err(|e| {
+        Error::custom(format!(
+            "Failed to read proof from buffer: {}. Value: {}",
+            e, proof
+        ))
+    })?;
+
+    Ok(proof)
+}
+
+pub fn serialize_proof(proof: &Proof) -> String {
+    let mut buffer = Vec::new();
+    use plonky2::util::serialization::Write;
+    buffer.write_proof(proof).unwrap();
+    serialize_bytes(&buffer)
+}