[WIP] cosmos-tx: MsgSend support w\ integration test

Basic support for `MsgSend` with end-to-end integration test.

Adds the following:

- Traits for simplifying Protobuf serialization:
  - `prost_ext::MessageExt` for Protobuf encoding
  - `msg::MsgType` and `msg::MsgProto` for decoding/encoding `Msg`
    types as Protobuf `Any` messages.
- Domain types which model the following:
  - `Coin`: amount to send and a denom
  - `Denom`: name of a particular denomination
  - `Fee`: transaction fees
  - `MsgSend`: transaction message for performing a simple send

Additionally includes an end-to-end test which uses Docker to spawn a
single-node `gaia` and send a transaction.

.github/workflows/cosmos-tx.yml

@@ -52,4 +52,5 @@ jobs:
           profile: minimal
           toolchain: ${{ matrix.rust }}
           override: true
+      - run: cargo build --release --all-features # TODO(tarcieri): just test with --all-features
       - run: cargo test --release

cosmos-tx/Cargo.toml

@@ -17,7 +17,18 @@ eyre = "0.6"
 k256 = { version = "0.7", features = ["ecdsa", "sha256"] }
 prost = "0.7"
 prost-types = "0.7"
-rand_core = "0.5"
-rust_decimal = "1.9"
-tendermint = { version = "0.19", features = ["secp256k1"] }
+rand_core = { version = "0.5", features = ["std"] }
+subtle-encoding = { version = "0.5", features = ["bech32-preview"] }
+tendermint = { version = "0.19", default-features = false, features = ["secp256k1"] }
+tendermint-rpc = { version = "0.19", optional = true, features = ["http-client"] }
 thiserror = "1"
+
+[dev-dependencies]
+tokio = "1"
+
+[features]
+rpc = ["tendermint-rpc"]
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]

cosmos-tx/src/bank.rs

@@ -0,0 +1,73 @@
+//! Bank module support
+//!
+//! <https://docs.cosmos.network/master/modules/bank/>
+
+use crate::{
+    tx::{Msg, MsgType},
+    AccountId, Coin, Result,
+};
+use cosmos_sdk_proto::cosmos;
+use std::convert::{TryFrom, TryInto};
+
+/// MsgSend represents a message to send coins from one account to another.
+#[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
+pub struct MsgSend {
+    /// Sender's address.
+    pub from_address: AccountId,
+
+    /// Recipient's address.
+    pub to_address: AccountId,
+
+    /// Amount to send
+    pub amount: Vec<Coin>,
+}
+
+impl MsgType for MsgSend {
+    fn from_msg(msg: &Msg) -> Result<Self> {
+        cosmos::bank::v1beta1::MsgSend::from_msg(msg).and_then(TryInto::try_into)
+    }
+
+    fn to_msg(&self) -> Result<Msg> {
+        cosmos::bank::v1beta1::MsgSend::from(self).to_msg()
+    }
+}
+
+impl TryFrom<cosmos::bank::v1beta1::MsgSend> for MsgSend {
+    type Error = eyre::Report;
+
+    fn try_from(proto: cosmos::bank::v1beta1::MsgSend) -> Result<MsgSend> {
+        MsgSend::try_from(&proto)
+    }
+}
+
+impl TryFrom<&cosmos::bank::v1beta1::MsgSend> for MsgSend {
+    type Error = eyre::Report;
+
+    fn try_from(proto: &cosmos::bank::v1beta1::MsgSend) -> Result<MsgSend> {
+        Ok(MsgSend {
+            from_address: proto.from_address.parse()?,
+            to_address: proto.to_address.parse()?,
+            amount: proto
+                .amount
+                .iter()
+                .map(TryFrom::try_from)
+                .collect::<Result<_, _>>()?,
+        })
+    }
+}
+
+impl From<MsgSend> for cosmos::bank::v1beta1::MsgSend {
+    fn from(coin: MsgSend) -> cosmos::bank::v1beta1::MsgSend {
+        cosmos::bank::v1beta1::MsgSend::from(&coin)
+    }
+}
+
+impl From<&MsgSend> for cosmos::bank::v1beta1::MsgSend {
+    fn from(msg: &MsgSend) -> cosmos::bank::v1beta1::MsgSend {
+        cosmos::bank::v1beta1::MsgSend {
+            from_address: msg.from_address.to_string(),
+            to_address: msg.to_address.to_string(),
+            amount: msg.amount.iter().map(Into::into).collect(),
+        }
+    }
+}

cosmos-tx/src/base.rs

@@ -0,0 +1,171 @@
+//! Base functionality.
+
+use crate::{Decimal, Error, Result};
+use cosmos_sdk_proto::cosmos;
+use std::{
+    convert::{TryFrom, TryInto},
+    fmt,
+    str::FromStr,
+};
+use subtle_encoding::bech32;
+
+/// Account identifiers
+#[derive(Clone, Eq, PartialEq, PartialOrd, Ord)]
+pub struct AccountId {
+    /// Account ID encoded as Bech32
+    bech32: String,
+
+    /// Length of the human-readable prefix of the address
+    hrp_length: usize,
+}
+
+impl AccountId {
+    /// Create an [`AccountId`] with the given human-readable prefix and
+    /// public key hash.
+    pub fn new(prefix: &str, bytes: [u8; tendermint::account::LENGTH]) -> Result<Self> {
+        let id = bech32::encode(prefix, &bytes);
+
+        // TODO(tarcieri): ensure this is the proper validation for an account prefix
+        if prefix.chars().all(|c| matches!(c, 'a'..='z')) {
+            Ok(Self {
+                bech32: id,
+                hrp_length: prefix.len(),
+            })
+        } else {
+            Err(Error::AccountId { id }.into())
+        }
+    }
+
+    /// Get the human-readable prefix of this account.
+    pub fn prefix(&self) -> &str {
+        &self.bech32[..self.hrp_length]
+    }
+
+    /// Decode an account ID from Bech32 to an inner byte value.
+    pub fn to_bytes(&self) -> [u8; tendermint::account::LENGTH] {
+        bech32::decode(&self.bech32)
+            .ok()
+            .and_then(|result| result.1.try_into().ok())
+            .expect("malformed Bech32 AccountId")
+    }
+}
+
+impl AsRef<str> for AccountId {
+    fn as_ref(&self) -> &str {
+        &self.bech32
+    }
+}
+
+impl fmt::Debug for AccountId {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_tuple("AccountId").field(&self.as_ref()).finish()
+    }
+}
+
+impl fmt::Display for AccountId {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.write_str(self.as_ref())
+    }
+}
+
+impl FromStr for AccountId {
+    type Err = eyre::Report;
+
+    fn from_str(s: &str) -> Result<Self> {
+        let (hrp, bytes) = bech32::decode(s)?;
+
+        if bytes.len() == tendermint::account::LENGTH {
+            Ok(Self {
+                bech32: s.to_owned(),
+                hrp_length: hrp.len(),
+            })
+        } else {
+            Err(Error::AccountId { id: s.to_owned() }.into())
+        }
+    }
+}
+
+impl From<AccountId> for tendermint::account::Id {
+    fn from(id: AccountId) -> tendermint::account::Id {
+        tendermint::account::Id::from(&id)
+    }
+}
+
+impl From<&AccountId> for tendermint::account::Id {
+    fn from(id: &AccountId) -> tendermint::account::Id {
+        tendermint::account::Id::new(id.to_bytes())
+    }
+}
+
+/// Coin defines a token with a denomination and an amount.
+#[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
+pub struct Coin {
+    /// Denomination
+    pub denom: Denom,
+
+    /// Amount
+    pub amount: Decimal,
+}
+
+impl TryFrom<cosmos::base::v1beta1::Coin> for Coin {
+    type Error = eyre::Report;
+
+    fn try_from(proto: cosmos::base::v1beta1::Coin) -> Result<Coin> {
+        Coin::try_from(&proto)
+    }
+}
+
+impl TryFrom<&cosmos::base::v1beta1::Coin> for Coin {
+    type Error = eyre::Report;
+
+    fn try_from(proto: &cosmos::base::v1beta1::Coin) -> Result<Coin> {
+        Ok(Coin {
+            denom: proto.denom.parse()?,
+            amount: proto.amount.parse()?,
+        })
+    }
+}
+
+impl From<Coin> for cosmos::base::v1beta1::Coin {
+    fn from(coin: Coin) -> cosmos::base::v1beta1::Coin {
+        cosmos::base::v1beta1::Coin::from(&coin)
+    }
+}
+
+impl From<&Coin> for cosmos::base::v1beta1::Coin {
+    fn from(coin: &Coin) -> cosmos::base::v1beta1::Coin {
+        cosmos::base::v1beta1::Coin {
+            denom: coin.denom.to_string(),
+            amount: coin.amount.to_string(),
+        }
+    }
+}
+
+/// Denomination.
+#[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Ord)]
+pub struct Denom(String);
+
+impl AsRef<str> for Denom {
+    fn as_ref(&self) -> &str {
+        self.0.as_ref()
+    }
+}
+
+impl fmt::Display for Denom {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.write_str(self.as_ref())
+    }
+}
+
+impl FromStr for Denom {
+    type Err = eyre::Report;
+
+    fn from_str(s: &str) -> Result<Self> {
+        // TODO(tarcieri): ensure this is the proper validation for a denom name
+        if s.chars().all(|c| matches!(c, 'a'..='z')) {
+            Ok(Denom(s.to_owned()))
+        } else {
+            Err(Error::Denom { name: s.to_owned() }.into())
+        }
+    }
+}