Move protobuf traits from cosmrs => cosmos-sdk-proto (#255)

When trying to define an `osmosis-proto` crate (#239), we ran into the
problem that it needed to import `cosmrs` to be able to impl the
`MsgProto` trait.

We couldn't follow the same pattern as `cosmrs` defining the type URLs
for `cosmos-sdk-proto`, which it could only do because it defined the
`MsgProto` trait as well.

Knowledge of the type URLs is necessary to convert to/from `Any`, which
Cosmos SDK uses all over the place.

So far there isn't a good upstream solution to this problem in `prost`
or AFAICT in `tendermint-proto` either. There's an upstream tracking
issue for `prost` here:

tokio-rs/prost#299

The ideal solution to this problem seems to be adding a `TYPE_URL` to
`prost::Message`, and automatically populating them with `prost-build`.

Failing that, this commit introduces a `TypeUrl` trait with an
associated `TYPE_URL` const (previously provided by the `MsgProto`
trait).

The `from_any` and `to_any` methods have been moved to `MessageExt`.

cosmos-sdk-proto/src/lib.rs

@@ -7,6 +7,11 @@
 #![forbid(unsafe_code)]
 #![warn(trivial_casts, trivial_numeric_casts, unused_import_braces)]
 
+pub mod traits;
+pub mod type_urls;
+
+pub use prost;
+pub use prost_types::Any;
 pub use tendermint_proto as tendermint;
 
 /// The version (commit hash) of the Cosmos SDK used when generating this library.

cosmos-sdk-proto/src/traits.rs

@@ -0,0 +1,76 @@
+//! Support traits for Cosmos SDK protobufs.
+
+pub use prost::Message;
+
+use crate::Any;
+use prost::{DecodeError, EncodeError};
+use std::str::FromStr;
+
+/// Associate a type URL with a given proto.
+pub trait TypeUrl: Message {
+    /// Type URL value
+    const TYPE_URL: &'static str;
+}
+
+/// Extension trait for [`Message`].
+pub trait MessageExt: Message {
+    /// Parse this message proto from [`Any`].
+    fn from_any(any: &Any) -> Result<Self, DecodeError>
+    where
+        Self: Default + Sized + TypeUrl,
+    {
+        if any.type_url == Self::TYPE_URL {
+            Ok(Self::decode(&*any.value)?)
+        } else {
+            let mut err = DecodeError::new(format!(
+                "expected type URL: \"{}\" (got: \"{}\")",
+                Self::TYPE_URL,
+                &any.type_url
+            ));
+            err.push("unexpected type URL", "type_url");
+            Err(err)
+        }
+    }
+
+    /// Serialize this message proto as [`Any`].
+    fn to_any(&self) -> Result<Any, EncodeError>
+    where
+        Self: TypeUrl,
+    {
+        self.to_bytes().map(|bytes| Any {
+            type_url: Self::TYPE_URL.to_owned(),
+            value: bytes,
+        })
+    }
+
+    /// Serialize this protobuf message as a byte vector.
+    fn to_bytes(&self) -> Result<Vec<u8>, EncodeError>;
+}
+
+impl<M> MessageExt for M
+where
+    M: prost::Message,
+{
+    fn to_bytes(&self) -> Result<Vec<u8>, EncodeError> {
+        let mut bytes = Vec::new();
+        Message::encode(self, &mut bytes)?;
+        Ok(bytes)
+    }
+}
+
+/// Extension traits for optionally parsing non-empty strings.
+///
+/// This is a common pattern in Cosmos SDK protobufs.
+pub trait ParseOptional: AsRef<str> {
+    /// Parse optional field.
+    fn parse_optional<T: FromStr>(&self) -> Result<Option<T>, T::Err> {
+        if self.as_ref().is_empty() {
+            Ok(None)
+        } else {
+            Ok(Some(self.as_ref().parse()?))
+        }
+    }
+}
+
+impl ParseOptional for str {}
+impl ParseOptional for String {}

cosmos-sdk-proto/src/type_urls.rs

@@ -0,0 +1,134 @@
+//! Registry of type URLs associated with various protobuf types defined in
+//! this crate.
+
+// TODO(tarcieri): leverage first-class support for type URLs in prost?
+// See: https://github.com/tokio-rs/prost/issues/299
+
+use crate::{cosmos, traits::TypeUrl};
+
+#[cfg(feature = "cosmwasm")]
+use crate::cosmwasm;
+
+impl TypeUrl for cosmos::bank::v1beta1::MsgSend {
+    const TYPE_URL: &'static str = "/cosmos.bank.v1beta1.MsgSend";
+}
+
+impl TypeUrl for cosmos::bank::v1beta1::MsgMultiSend {
+    const TYPE_URL: &'static str = "/cosmos.bank.v1beta1.MsgMultiSend";
+}
+
+impl TypeUrl for cosmos::distribution::v1beta1::MsgSetWithdrawAddress {
+    const TYPE_URL: &'static str = "/cosmos.distribution.v1beta1.MsgSetWithdrawAddress";
+}
+
+impl TypeUrl for cosmos::distribution::v1beta1::MsgWithdrawDelegatorReward {
+    const TYPE_URL: &'static str = "/cosmos.distribution.v1beta1.MsgWithdrawDelegatorReward";
+}
+
+impl TypeUrl for cosmos::distribution::v1beta1::MsgWithdrawValidatorCommission {
+    const TYPE_URL: &'static str = "/cosmos.distribution.v1beta1.MsgWithdrawValidatorCommission";
+}
+
+impl TypeUrl for cosmos::distribution::v1beta1::MsgFundCommunityPool {
+    const TYPE_URL: &'static str = "/cosmos.distribution.v1beta1.MsgFundCommunityPool";
+}
+
+impl TypeUrl for cosmos::feegrant::v1beta1::MsgGrantAllowance {
+    const TYPE_URL: &'static str = "/cosmos.feegrant.v1beta1.MsgGrantAllowance";
+}
+
+impl TypeUrl for cosmos::feegrant::v1beta1::MsgRevokeAllowance {
+    const TYPE_URL: &'static str = "/cosmos.feegrant.v1beta1.MsgRevokeAllowance";
+}
+
+impl TypeUrl for cosmos::feegrant::v1beta1::BasicAllowance {
+    const TYPE_URL: &'static str = "/cosmos.feegrant.v1beta1.BasicAllowance";
+}
+
+impl TypeUrl for cosmos::feegrant::v1beta1::PeriodicAllowance {
+    const TYPE_URL: &'static str = "/cosmos.feegrant.v1beta1.PeriodicAllowance";
+}
+
+impl TypeUrl for cosmos::feegrant::v1beta1::AllowedMsgAllowance {
+    const TYPE_URL: &'static str = "/cosmos.feegrant.v1beta1.AllowedMsgAllowance";
+}
+
+impl TypeUrl for cosmos::staking::v1beta1::MsgDelegate {
+    const TYPE_URL: &'static str = "/cosmos.staking.v1beta1.MsgDelegate";
+}
+
+impl TypeUrl for cosmos::staking::v1beta1::MsgUndelegate {
+    const TYPE_URL: &'static str = "/cosmos.staking.v1beta1.MsgUndelegate";
+}
+
+impl TypeUrl for cosmos::staking::v1beta1::MsgBeginRedelegate {
+    const TYPE_URL: &'static str = "/cosmos.staking.v1beta1.MsgBeginRedelegate";
+}
+
+impl TypeUrl for cosmos::base::abci::v1beta1::MsgData {
+    const TYPE_URL: &'static str = "/cosmos.base.v1beta1.abci.MsgData";
+}
+
+impl TypeUrl for cosmos::base::abci::v1beta1::TxMsgData {
+    const TYPE_URL: &'static str = "/cosmos.base.v1beta1.abci.TxMsgData";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgStoreCode {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgStoreCode";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgInstantiateContract {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgInstantiateContract";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgExecuteContract {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgExecuteContract";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgMigrateContract {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgMigrateContract";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgUpdateAdmin {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgUpdateAdmin";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgClearAdmin {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgClearAdmin";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgStoreCodeResponse {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgStoreCodeResponse";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgInstantiateContractResponse {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgInstantiateContractResponse";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgExecuteContractResponse {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgExecuteContractResponse";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgMigrateContractResponse {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgMigrateContractResponse";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgUpdateAdminResponse {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgUpdateAdminResponse";
+}
+
+#[cfg(feature = "cosmwasm")]
+impl TypeUrl for cosmwasm::wasm::v1::MsgClearAdminResponse {
+    const TYPE_URL: &'static str = "/cosmwasm.wasm.v1.MsgClearAdminResponse";
+}

cosmrs/src/cosmwasm.rs

@@ -5,7 +5,9 @@
 
 pub use crate::proto::cosmwasm::wasm::v1::AccessType;
 use crate::{
-    prost_ext::ParseOptional, proto, tx::Msg, AccountId, Coin, Error, ErrorReport, Result,
+    proto::{self, traits::ParseOptional},
+    tx::Msg,
+    AccountId, Coin, Error, ErrorReport, Result,
 };
 use cosmos_sdk_proto::cosmwasm::wasm::v1::ContractCodeHistoryOperationType;
 

cosmrs/src/crypto/legacy_amino.rs

@@ -1,7 +1,10 @@
 //! Legacy Amino support.
 
 use super::PublicKey;
-use crate::{prost_ext::MessageExt, proto, Any, Error, ErrorReport, Result};
+use crate::{
+    proto::{self, traits::MessageExt},
+    Any, Error, ErrorReport, Result,
+};
 use eyre::WrapErr;
 use prost::Message;
 

cosmrs/src/crypto/public_key.rs

@@ -1,9 +1,13 @@
 //! Public keys
 
-use crate::{prost_ext::MessageExt, proto, AccountId, Error, ErrorReport, Result};
+use crate::{
+    proto::{
+        self,
+        traits::{Message, MessageExt},
+    },
+    AccountId, Any, Error, ErrorReport, Result,
+};
 use eyre::WrapErr;
-use prost::Message;
-use prost_types::Any;
 use serde::{Deserialize, Serialize};
 use std::str::FromStr;
 use subtle_encoding::base64;
@@ -57,13 +61,13 @@ impl PublicKey {
             tendermint::PublicKey::Ed25519(_) => proto::cosmos::crypto::secp256k1::PubKey {
                 key: self.to_bytes(),
             }
-            .to_bytes(),
+            .to_bytes()?,
             tendermint::PublicKey::Secp256k1(_) => proto::cosmos::crypto::secp256k1::PubKey {
                 key: self.to_bytes(),
             }
-            .to_bytes(),
-            _ => Err(Error::Crypto.into()),
-        }?;
+            .to_bytes()?,
+            _ => return Err(Error::Crypto.into()),
+        };
 
         Ok(Any {
             type_url: self.type_url().to_owned(),

cosmrs/src/lib.rs

@@ -45,7 +45,6 @@ pub mod dev;
 
 mod base;
 mod error;
-mod prost_ext;
 
 pub use crate::{
     base::{AccountId, Coin, Denom},

cosmrs/src/tx.rs

@@ -117,12 +117,15 @@ pub use self::{
     body::Body,
     fee::Fee,
     mode_info::ModeInfo,
-    msg::{Msg, MsgProto},
+    msg::Msg,
     raw::Raw,
     sign_doc::SignDoc,
     signer_info::{SignerInfo, SignerPublicKey},
 };
-pub use crate::{proto::cosmos::tx::signing::v1beta1::SignMode, ErrorReport};
+pub use crate::{
+    proto::{cosmos::tx::signing::v1beta1::SignMode, traits::MessageExt},
+    ErrorReport,
+};
 pub use tendermint::abci::{transaction::Hash, Gas};
 
 use crate::{proto, Error, Result};

cosmrs/src/tx/auth_info.rs

@@ -1,7 +1,10 @@
 //! Auth info.
 
 use super::{Fee, SignerInfo};
-use crate::{prost_ext::MessageExt, proto, Error, ErrorReport, Result};
+use crate::{
+    proto::{self, traits::MessageExt},
+    Error, ErrorReport, Result,
+};
 
 /// [`AuthInfo`] describes the fee and signer modes that are used to sign a transaction.
 #[derive(Clone, Debug, Eq, PartialEq)]
@@ -29,7 +32,7 @@ impl AuthInfo {
 
     /// Encode this type using Protocol Buffers.
     pub fn into_bytes(self) -> Result<Vec<u8>> {
-        self.into_proto().to_bytes()
+        Ok(self.into_proto().to_bytes()?)
     }
 }
 

cosmrs/src/tx/body.rs

@@ -1,6 +1,9 @@
 //! Transaction bodies.
 
-use crate::{prost_ext::MessageExt, proto, ErrorReport, Result};
+use crate::{
+    proto::{self, traits::MessageExt},
+    ErrorReport, Result,
+};
 use prost_types::Any;
 use tendermint::block;
 
@@ -63,7 +66,7 @@ impl Body {
 
     /// Encode this type using Protocol Buffers.
     pub fn into_bytes(self) -> Result<Vec<u8>> {
-        self.into_proto().to_bytes()
+        Ok(self.into_proto().to_bytes()?)
     }
 }