save witness in binary

plonky2x-verifier/prover.go

@@ -106,16 +106,12 @@ func Prove(circuitPath string, r1cs constraint.ConstraintSystem, pk groth16.Prov
 		return nil, nil, fmt.Errorf("failed to get public witness: %w", err)
 	}
 
-	jsonPublicWitness, err := json.Marshal(publicWitness)
-	if err != nil {
-		return nil, nil, fmt.Errorf("failed to marshal public witness: %w", err)
-	}
-	log.Info().Msg("Saving public witness to " + circuitPath + "/public_witness.json")
+	log.Info().Msg("Saving public witness to " + circuitPath + "/public_witness.bin")
 	witnessFile, err := os.Create(circuitPath + "/public_witness.json")
 	if err != nil {
 		return nil, nil, fmt.Errorf("failed to create public witness file: %w", err)
 	}
-	_, err = witnessFile.Write(jsonPublicWitness)
+	_, err = publicWitness.WriteTo(witnessFile)
 	if err != nil {
 		return nil, nil, fmt.Errorf("failed to write public witness file: %w", err)
 	}

plonky2x-verifier/verifier.go

@@ -37,22 +37,15 @@ func LoadVerifierKey(path string) (groth16.VerifyingKey, error) {
 
 func LoadPublicWitness(circuitPath string) (witness.Witness, error) {
 	log := logger.Logger()
-	witnessFile, err := os.Open(circuitPath + "/public_witness.json")
+	witnessFile, err := os.Open(circuitPath + "/public_witness.bin")
 	if err != nil {
 		return nil, fmt.Errorf("failed to open public witness file: %w", err)
 	}
 	publicWitness, err := witness.New(ecc.BN254.ScalarField())
 	if err != nil {
 		return nil, fmt.Errorf("failed to create public witness: %w", err)
 	}
-	jsonPublicWitness, err := io.ReadAll(witnessFile)
-	if err != nil {
-		return nil, fmt.Errorf("failed to read public witness file: %w", err)
-	}
-	err = json.Unmarshal(jsonPublicWitness, publicWitness)
-	if err != nil {
-		return nil, fmt.Errorf("failed to read public witness file: %w", err)
-	}
+	publicWitness.ReadFrom(witnessFile)
 	witnessFile.Close()
 	log.Debug().Msg("Successfully loaded public witness")