cosmos · tony-iqlusion · Aug 8, 2022 · Jul 22, 2022
diff --git a/cosmrs/src/error.rs b/cosmrs/src/error.rs
@@ -46,7 +46,7 @@ pub enum Error {
         /// Expected type URL.
         expected: &'static str,
 
-        /// Actual type URL found in the [`prost_types::Any`] message.
+        /// Actual type URL found in the [`crate::Any`] message.
         found: String,
     },
 

diff --git a/cosmrs/src/tx.rs b/cosmrs/src/tx.rs
@@ -106,6 +106,7 @@ pub mod mode_info;
 
 mod auth_info;
 mod body;
+mod builder;
 mod fee;
 mod msg;
 mod raw;
@@ -115,6 +116,7 @@ mod signer_info;
 pub use self::{
     auth_info::AuthInfo,
     body::Body,
+    builder::BodyBuilder,
     fee::Fee,
     mode_info::ModeInfo,
     msg::Msg,

diff --git a/cosmrs/src/tx/body.rs b/cosmrs/src/tx/body.rs
@@ -2,9 +2,8 @@
 
 use crate::{
     proto::{self, traits::MessageExt},
-    ErrorReport, Result,
+    Any, ErrorReport, Result,
 };
-use prost_types::Any;
 use tendermint::block;
 
 /// [`Body`] of a transaction that all signers sign over.
@@ -70,6 +69,12 @@ impl Body {
     }
 }
 
+impl Default for Body {
+    fn default() -> Body {
+        Self::new([], "", 0u8)
+    }
+}
+
 impl From<Body> for proto::cosmos::tx::v1beta1::TxBody {
     fn from(body: Body) -> proto::cosmos::tx::v1beta1::TxBody {
         proto::cosmos::tx::v1beta1::TxBody {

diff --git a/cosmrs/src/tx/builder.rs b/cosmrs/src/tx/builder.rs
@@ -0,0 +1,73 @@
+//! Transaction builder.
+
+use super::Body;
+use crate::Any;
+use tendermint::block;
+
+/// Transaction [`Body`] builder which simplifies incrementally assembling and
+/// signing a transaction.
+#[derive(Clone, Debug, Default)]
+pub struct BodyBuilder {
+    /// Transaction body in-progress.
+    body: Body,
+}
+
+impl BodyBuilder {
+    /// Create a new transaction builder in the default state.
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Add a message to the transaction.
+    pub fn msg(&mut self, msg: impl Into<Any>) -> &mut Self {
+        self.body.messages.push(msg.into());
+        self
+    }
+
+    /// Add multiple messages to the transaction.
+    pub fn msgs(&mut self, msgs: impl IntoIterator<Item = Any>) -> &mut Self {
+        self.body.messages.extend(msgs);
+        self
+    }
+
+    /// Set the transaction memo.
+    pub fn memo(&mut self, memo: impl Into<String>) -> &mut Self {
+        self.body.memo = memo.into();
+        self
+    }
+
+    /// Set the timeout height.
+    pub fn timeout_height(&mut self, height: impl Into<block::Height>) -> &mut Self {
+        self.body.timeout_height = height.into();
+        self
+    }
+
+    /// Add an extension option.
+    pub fn extension_option(&mut self, option: impl Into<Any>) -> &mut Self {
+        self.body.extension_options.push(option.into());
+        self
+    }
+
+    /// Add a non-critical extension option.
+    pub fn non_critical_extension_option(&mut self, option: impl Into<Any>) -> &mut Self {
+        self.body.extension_options.push(option.into());
+        self
+    }
+
+    /// Return the finished [`Body`].
+    pub fn finish(&self) -> Body {
+        self.into()
+    }
+}
+
+impl From<BodyBuilder> for Body {
+    fn from(builder: BodyBuilder) -> Body {
+        builder.body
+    }
+}
+
+impl From<&BodyBuilder> for Body {
+    fn from(builder: &BodyBuilder) -> Body {
+        builder.body.clone()
+    }
+}
diff --git a/cosmrs/tests/integration.rs b/cosmrs/tests/integration.rs
@@ -60,9 +60,8 @@ fn msg_send() {
     let sequence_number = 0;
     let gas = 100_000;
     let fee = Fee::from_amount_and_gas(amount, gas);
-    let timeout_height = 9001u16;
 
-    let tx_body = tx::Body::new(vec![msg_send], MEMO, timeout_height);
+    let tx_body = tx::BodyBuilder::new().msg(msg_send).memo(MEMO).finish();
     let auth_info =
         SignerInfo::single_direct(Some(sender_public_key), sequence_number).auth_info(fee);
     let sign_doc = SignDoc::new(&tx_body, &auth_info, &chain_id, ACCOUNT_NUMBER).unwrap();