From cf3b9fc0f0725b0076414e67488553634b629670 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andrzej=20Bro=C5=84ski?= <andrzej1_1@o2.pl>
Date: Tue, 26 Mar 2024 13:32:16 +0100
Subject: [PATCH] Decouple `Withdraw` structure from request handling.

---
 kairos-server/src/routes/withdraw.rs | 44 +++++++++++++++-------------
 1 file changed, 23 insertions(+), 21 deletions(-)

diff --git a/kairos-server/src/routes/withdraw.rs b/kairos-server/src/routes/withdraw.rs
index 3fb72bc5..7f746331 100644
--- a/kairos-server/src/routes/withdraw.rs
+++ b/kairos-server/src/routes/withdraw.rs
@@ -21,36 +21,37 @@ pub struct Withdrawal {
 pub async fn withdraw_handler(
     _: WithdrawPath,
     State(state): State<LockedBatchState>,
-    Json(withdrawal): Json<Withdrawal>,
+    Json(Withdrawal {
+        public_key,
+        signature,
+        amount,
+    }): Json<Withdrawal>,
 ) -> Result<(), AppErr> {
     tracing::info!("TODO: verifying withdrawal signature");
 
     tracing::info!("verifying withdrawal sender has sufficient funds");
-    check_sender_funds(&state, &withdrawal).await?;
+    check_sender_funds(&state, &public_key, amount).await?;
 
     tracing::info!("TODO: adding withdrawal to batch");
 
     let mut state = state.write().await;
-    let from_balance = state
-        .balances
-        .get_mut(&withdrawal.public_key)
-        .ok_or_else(|| {
-            AppErr::set_status(
-                anyhow!(
-                    "Sender no longer has an account.
+    let from_balance = state.balances.get_mut(&public_key).ok_or_else(|| {
+        AppErr::set_status(
+            anyhow!(
+                "Sender no longer has an account.
                 The sender just removed all their funds."
-                ),
-                StatusCode::CONFLICT,
-            )
-        })?;
+            ),
+            StatusCode::CONFLICT,
+        )
+    })?;
 
-    let updated_balance = from_balance.checked_sub(withdrawal.amount).ok_or_else(|| {
+    let updated_balance = from_balance.checked_sub(amount).ok_or_else(|| {
         AppErr::set_status(
             anyhow!(
                 "Sender no longer has sufficient funds, balance={}, withdrawal_amount={}.
                 The sender just moved their funds in a concurrent request",
                 from_balance,
-                withdrawal.amount
+                amount
             ),
             StatusCode::CONFLICT,
         )
@@ -59,12 +60,12 @@ pub async fn withdraw_handler(
     *from_balance = updated_balance;
 
     if updated_balance == 0 {
-        state.balances.remove(&withdrawal.public_key);
+        state.balances.remove(&public_key);
     }
 
     tracing::info!(
         "Updated account public_key={:?} balance={}",
-        withdrawal.public_key,
+        public_key,
         updated_balance
     );
 
@@ -73,19 +74,20 @@ pub async fn withdraw_handler(
 
 async fn check_sender_funds(
     state: &LockedBatchState,
-    withdrawal: &Withdrawal,
+    public_key: &PublicKey,
+    amount: u64,
 ) -> Result<(), AppErr> {
     let state = state.read().await;
-    let from_balance = state.balances.get(&withdrawal.public_key).ok_or_else(|| {
+    let from_balance = state.balances.get(public_key).ok_or_else(|| {
         AppErr::set_status(anyhow!("Withdrawer has no account."), StatusCode::CONFLICT)
     })?;
 
-    if *from_balance < withdrawal.amount {
+    if *from_balance < amount {
         return Err(AppErr::set_status(
             anyhow!(
                 "Withdrawer has insufficient funds, balance={}, withdrawal_amount={}.",
                 from_balance,
-                withdrawal.amount
+                amount
             ),
             StatusCode::FORBIDDEN,
         ));