move pod data's deserialization to RecursivePod trait (#294), expose get_common_data (#300)

src/backends/plonky2/emptypod.rs

@@ -158,23 +158,6 @@ impl EmptyPod {
         })
         .map_err(|e| Error::custom(format!("EmptyPod proof verification failure: {:?}", e)))
     }
-
-    pub(crate) fn deserialize(
-        params: Params,
-        id: PodId,
-        vds_root: Hash,
-        data: serde_json::Value,
-    ) -> Result<Box<dyn RecursivePod>> {
-        let data: Data = serde_json::from_value(data)?;
-        let circuit_data = &*STANDARD_REC_MAIN_POD_CIRCUIT_DATA;
-        let proof = deserialize_proof(&circuit_data.common, &data.proof)?;
-        Ok(Box::new(Self {
-            params,
-            id,
-            vds_root,
-            proof,
-        }))
-    }
 }
 
 #[derive(Serialize, Deserialize)]
@@ -220,6 +203,22 @@ impl RecursivePod for EmptyPod {
     fn vds_root(&self) -> Hash {
         self.vds_root
     }
+    fn deserialize_data(
+        params: Params,
+        data: serde_json::Value,
+        vds_root: Hash,
+        id: PodId,
+    ) -> Result<Box<dyn RecursivePod>, Box<DynError>> {
+        let data: Data = serde_json::from_value(data)?;
+        let circuit_data = &*STANDARD_REC_MAIN_POD_CIRCUIT_DATA;
+        let proof = deserialize_proof(&circuit_data.common, &data.proof)?;
+        Ok(Box::new(Self {
+            params,
+            id,
+            vds_root,
+            proof,
+        }))
+    }
 }
 
 #[cfg(test)]

src/backends/plonky2/mainpod/mod.rs

@@ -581,7 +581,7 @@ pub struct MainPod {
 // a serialized proof. At some point in the future, this data may be available
 // as a constant or with static initialization, but in the meantime we can
 // generate it on-demand.
-fn get_common_data(params: &Params) -> Result<CommonCircuitData<F, D>, Error> {
+pub fn get_common_data(params: &Params) -> Result<CommonCircuitData<F, D>, Error> {
     // TODO: Cache this somehow
     // https://github.com/0xPARC/pod2/issues/247
     let rec_circuit_data = &*STANDARD_REC_MAIN_POD_CIRCUIT_DATA;
@@ -643,24 +643,6 @@ impl MainPod {
     pub fn params(&self) -> &Params {
         &self.params
     }
-
-    pub(crate) fn deserialize(
-        params: Params,
-        id: PodId,
-        vds_root: Hash,
-        data: serde_json::Value,
-    ) -> Result<Box<dyn RecursivePod>> {
-        let data: Data = serde_json::from_value(data)?;
-        let common = get_common_data(&params)?;
-        let proof = deserialize_proof(&common, &data.proof)?;
-        Ok(Box::new(Self {
-            params,
-            id,
-            vds_root,
-            proof,
-            public_statements: data.public_statements,
-        }))
-    }
 }
 
 impl Pod for MainPod {
@@ -706,6 +688,23 @@ impl RecursivePod for MainPod {
     fn vds_root(&self) -> Hash {
         self.vds_root
     }
+    fn deserialize_data(
+        params: Params,
+        data: serde_json::Value,
+        vds_root: Hash,
+        id: PodId,
+    ) -> Result<Box<dyn RecursivePod>, Box<DynError>> {
+        let data: Data = serde_json::from_value(data)?;
+        let common = get_common_data(&params)?;
+        let proof = deserialize_proof(&common, &data.proof)?;
+        Ok(Box::new(Self {
+            params,
+            id,
+            vds_root,
+            proof,
+            public_statements: data.public_statements,
+        }))
+    }
 }
 
 #[cfg(test)]

src/backends/plonky2/mock/emptypod.rs

@@ -46,14 +46,6 @@ impl MockEmptyPod {
         }
         Ok(())
     }
-    pub(crate) fn deserialize(
-        params: Params,
-        id: PodId,
-        _vds_root: Hash,
-        _data: serde_json::Value,
-    ) -> Result<Box<dyn RecursivePod>> {
-        Ok(Box::new(Self { params, id }))
-    }
 }
 
 impl Pod for MockEmptyPod {
@@ -88,6 +80,14 @@ impl RecursivePod for MockEmptyPod {
     fn vds_root(&self) -> Hash {
         panic!("MockEmptyPod can't be verified in a recursive MainPod circuit");
     }
+    fn deserialize_data(
+        params: Params,
+        _data: serde_json::Value,
+        _vds_root: Hash,
+        id: PodId,
+    ) -> Result<Box<dyn RecursivePod>, Box<DynError>> {
+        Ok(Box::new(Self { params, id }))
+    }
 }
 
 #[cfg(test)]

src/backends/plonky2/mock/mainpod.rs

@@ -190,32 +190,6 @@ impl MockMainPod {
         })
     }
 
-    // MockMainPods include some internal private state which is necessary
-    // for verification. In non-mock Pods, this state will not be necessary,
-    // as the public statements can be verified using a ZK proof.
-    pub(crate) fn deserialize(
-        params: Params,
-        id: PodId,
-        vds_root: Hash,
-        data: serde_json::Value,
-    ) -> Result<Box<dyn RecursivePod>> {
-        let Data {
-            public_statements,
-            operations,
-            statements,
-            merkle_proofs,
-        } = serde_json::from_value(data)?;
-        Ok(Box::new(Self {
-            params,
-            id,
-            vds_root,
-            public_statements,
-            operations,
-            statements,
-            merkle_proofs,
-        }))
-    }
-
     fn _verify(&self) -> Result<()> {
         // 1. TODO: Verify input pods
 
@@ -331,6 +305,31 @@ impl RecursivePod for MockMainPod {
     fn vds_root(&self) -> Hash {
         self.vds_root
     }
+    // MockMainPods include some internal private state which is necessary
+    // for verification. In non-mock Pods, this state will not be necessary,
+    // as the public statements can be verified using a ZK proof.
+    fn deserialize_data(
+        params: Params,
+        data: serde_json::Value,
+        vds_root: Hash,
+        id: PodId,
+    ) -> Result<Box<dyn RecursivePod>, Box<DynError>> {
+        let Data {
+            public_statements,
+            operations,
+            statements,
+            merkle_proofs,
+        } = serde_json::from_value(data)?;
+        Ok(Box::new(Self {
+            params,
+            id,
+            vds_root,
+            public_statements,
+            operations,
+            statements,
+            merkle_proofs,
+        }))
+    }
 }
 
 #[cfg(test)]