Implement the http variant of the bank server.

During that process, many shortcomings with the socket server and the
bank lib were fixed.

I am aware a massive commit like this is not ideal.

.idea/bank-server.iml

@@ -3,6 +3,7 @@
   <component name="NewModuleRootManager">
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/bank/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/http-server/src" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/socket-server/src" isTestSource="false" />
       <excludeFolder url="file://$MODULE_DIR$/target" />
     </content>

Cargo.toml

@@ -2,5 +2,6 @@
 
 members = [
     "bank",
-    "socket-server"
+    "http-server",
+    "socket-server",
 ]

bank/Cargo.lock

@@ -8,7 +8,7 @@ version = "0.7.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1e37cfd5e7657ada45f742d6e99ca5788580b5c529dc78faf11ece6dc702656f"
 dependencies = [
- "memchr",
+    "memchr",
 ]
 
 [[package]]
@@ -23,20 +23,20 @@ version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
 dependencies = [
- "hermit-abi",
- "libc",
- "winapi",
+    "hermit-abi",
+    "libc",
+    "winapi",
 ]
 
 [[package]]
 name = "bank-server"
 version = "0.1.0"
 dependencies = [
- "anyhow",
- "log",
- "pretty_env_logger",
- "thiserror",
- "uuid",
+    "anyhow",
+    "log",
+    "pretty_env_logger",
+    "thiserror",
+    "uuid",
 ]
 
 [[package]]
@@ -51,11 +51,11 @@ version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "44533bbbb3bb3c1fa17d9f2e4e38bbbaf8396ba82193c4cb1b6445d711445d36"
 dependencies = [
- "atty",
- "humantime",
- "log",
- "regex",
- "termcolor",
+    "atty",
+    "humantime",
+    "log",
+    "regex",
+    "termcolor",
 ]
 
 [[package]]
@@ -64,9 +64,9 @@ version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d39cd93900197114fa1fcb7ae84ca742095eed9442088988ae74fa744e930e77"
 dependencies = [
- "cfg-if",
- "libc",
- "wasi",
+    "cfg-if",
+    "libc",
+    "wasi",
 ]
 
 [[package]]
@@ -75,7 +75,7 @@ version = "0.1.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "62b467343b94ba476dcb2500d242dadbb39557df889310ac77c5d99100aaac33"
 dependencies = [
- "libc",
+    "libc",
 ]
 
 [[package]]
@@ -84,7 +84,7 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "df004cfca50ef23c36850aaaa59ad52cc70d0e90243c3c7737a4dd32dc7a3c4f"
 dependencies = [
- "quick-error",
+    "quick-error",
 ]
 
 [[package]]
@@ -99,7 +99,7 @@ version = "0.4.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "51b9bbe6c47d51fc3e1a9b945965946b4c44142ab8792c50835a980d362c2710"
 dependencies = [
- "cfg-if",
+    "cfg-if",
 ]
 
 [[package]]
@@ -114,8 +114,8 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "926d36b9553851b8b0005f1275891b392ee4d2d833852c417ed025477350fb9d"
 dependencies = [
- "env_logger",
- "log",
+    "env_logger",
+    "log",
 ]
 
 [[package]]
@@ -124,7 +124,7 @@ version = "1.0.36"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c7342d5883fbccae1cc37a2353b09c87c9b0f3afd73f5fb9bba687a1f733b029"
 dependencies = [
- "unicode-xid",
+    "unicode-xid",
 ]
 
 [[package]]
@@ -139,7 +139,7 @@ version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "864d3e96a899863136fc6e99f3d7cae289dafe43bf2c5ac19b70df7210c0a145"
 dependencies = [
- "proc-macro2",
+    "proc-macro2",
 ]
 
 [[package]]
@@ -148,9 +148,9 @@ version = "1.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d07a8629359eb56f1e2fb1652bb04212c072a87ba68546a04065d525673ac461"
 dependencies = [
- "aho-corasick",
- "memchr",
- "regex-syntax",
+    "aho-corasick",
+    "memchr",
+    "regex-syntax",
 ]
 
 [[package]]
@@ -165,9 +165,9 @@ version = "1.0.86"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8a65b3f4ffa0092e9887669db0eae07941f023991ab58ea44da8fe8e2d511c6b"
 dependencies = [
- "proc-macro2",
- "quote",
- "unicode-xid",
+    "proc-macro2",
+    "quote",
+    "unicode-xid",
 ]
 
 [[package]]
@@ -176,7 +176,7 @@ version = "1.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bab24d30b911b2376f3a13cc2cd443142f0c81dda04c118693e35b3835757755"
 dependencies = [
- "winapi-util",
+    "winapi-util",
 ]
 
 [[package]]
@@ -185,7 +185,7 @@ version = "1.0.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "854babe52e4df1653706b98fcfc05843010039b406875930a70e4d9644e5c417"
 dependencies = [
- "thiserror-impl",
+    "thiserror-impl",
 ]
 
 [[package]]
@@ -194,9 +194,9 @@ version = "1.0.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aa32fd3f627f367fe16f893e2597ae3c05020f8bba2666a4e6ea73d377e5714b"
 dependencies = [
- "proc-macro2",
- "quote",
- "syn",
+    "proc-macro2",
+    "quote",
+    "syn",
 ]
 
 [[package]]
@@ -211,7 +211,7 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bc5cf98d8186244414c848017f0e2676b3fcb46807f6668a97dfe67359a3c4b7"
 dependencies = [
- "getrandom",
+    "getrandom",
 ]
 
 [[package]]
@@ -226,8 +226,8 @@ version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
 dependencies = [
- "winapi-i686-pc-windows-gnu",
- "winapi-x86_64-pc-windows-gnu",
+    "winapi-i686-pc-windows-gnu",
+    "winapi-x86_64-pc-windows-gnu",
 ]
 
 [[package]]
@@ -242,7 +242,7 @@ version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "70ec6ce85bb158151cae5e5c87f95a8e97d2c0c4b001223f33a334e3ce5de178"
 dependencies = [
- "winapi",
+    "winapi",
 ]
 
 [[package]]

bank/src/account.rs

@@ -1,19 +1,20 @@
 use std::hash::{Hash, Hasher};
 
-use anyhow::{bail, Result};
 use thiserror::Error;
 use uuid::Uuid;
 
-use crate::account::AccountError::{Inactive, InvalidAmount, Overdraw};
-
 #[derive(Error, Debug)]
 pub enum AccountError {
     #[error("can not overdraw account")]
-    Overdraw(),
+    Overdraw,
     #[error("account is inactive")]
-    Inactive(),
+    Inactive,
     #[error("amount must be > 0")]
-    InvalidAmount(),
+    InvalidAmount,
+    #[error("account does not exist")]
+    NotFound,
+    #[error("account still has a balance")]
+    AccountNotZero,
 }
 
 #[derive(Debug, Clone)]
@@ -52,33 +53,35 @@ impl Hash for Account {
 impl Account {
     #[cfg(test)]
     pub fn new() -> Self {
-        Self { ..Default::default() }
+        Self {
+            ..Default::default()
+        }
     }
 
-    pub fn deposit(&mut self, amount: f64) -> Result<()> {
+    pub fn deposit(&mut self, amount: f64) -> Result<f64, AccountError> {
         self.check_account(amount)?;
         self.balance += amount;
-        Ok(())
+        Ok(self.balance)
     }
 
-    pub fn withdraw(&mut self, amount: f64) -> Result<()> {
+    pub fn withdraw(&mut self, amount: f64) -> Result<f64, AccountError> {
         self.check_account(amount)?;
 
         if self.balance - amount < 0 as f64 {
-            bail!(Overdraw());
+            return Err(AccountError::Overdraw);
         }
         self.balance -= amount;
 
-        Ok(())
+        Ok(self.balance)
     }
 
-    fn check_account(&self, amount: f64) -> Result<()> {
+    fn check_account(&self, amount: f64) -> Result<(), AccountError> {
         if !self.is_active {
-            bail!(Inactive());
+            return Err(AccountError::Inactive);
         }
 
         if amount < 0 as f64 {
-            bail!(InvalidAmount());
+            return Err(AccountError::InvalidAmount);
         }
 
         Ok(())

bank/src/bank.rs

@@ -1,38 +1,61 @@
 use std::collections::{HashMap, HashSet};
-use std::sync::RwLock;
+use std::sync::{RwLock, RwLockReadGuard};
 
 #[cfg(test)]
 use anyhow::Result;
 
-use crate::account::Account;
+use crate::account::{Account, AccountError};
 
+#[derive(Default)]
 pub struct Bank {
     pub accounts: HashMap<String, RwLock<Account>>,
 }
 
 impl Bank {
     pub fn new() -> Self {
-        Self { accounts: HashMap::new() }
+        Default::default()
+    }
+
+    pub fn account_action<F: Fn(&mut Account) -> Result<f64, AccountError>>(
+        bank: RwLockReadGuard<'_, Bank>,
+        nr: &str,
+        action: F,
+    ) -> Result<f64, AccountError> {
+        match bank.accounts.get(nr) {
+            None => Err(AccountError::NotFound),
+            Some(account) => {
+                let mut account = account.write().unwrap();
+                action(&mut account)
+            }
+        }
     }
 
     pub fn account_numbers(&self) -> HashSet<String> {
-        self.accounts.iter()
+        self.accounts
+            .iter()
             .filter(|(_, acc)| acc.read().unwrap().is_active)
             .map(|(_, acc)| acc.read().unwrap().number.clone())
             .collect()
     }
 
     pub fn create_account(&mut self, owner: String) -> String {
-        let acc = Account { owner, ..Default::default() };
-        let number = acc.number.clone();
+        let acc = Account {
+            owner,
+            ..Default::default()
+        };
+        let nr = acc.number.clone();
 
         self.accounts.insert(acc.number.clone(), RwLock::new(acc));
 
-        number
+        nr
     }
 
-    #[cfg(test)]
-    pub fn transfer(&self, from: &mut Account, to: &mut Account, amount: f64) -> Result<()> {
+    pub fn transfer(
+        &self,
+        from: &mut Account,
+        to: &mut Account,
+        amount: f64,
+    ) -> Result<(), AccountError> {
         from.withdraw(amount)?;
         to.deposit(amount)?;
 

http-server/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "http-server"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+bank = { path = "../bank" }
+actix-web = "4.0.1"
+anyhow = "1.0.55"
+thiserror = "1.0.30"
+log = "0.4.14"
+pretty_env_logger = "0.4.0"
+serde = { version = "1.0.136", features = ["derive"] }
+
+[dev-dependencies]
+serde_json = "1.0.79"

http-server/src/handlers/close_account.rs

@@ -0,0 +1,29 @@
+use actix_web::{post, web, HttpResponse, Responder, Result};
+
+use bank::account::AccountError;
+use bank::bank::Bank;
+
+use crate::handlers::error::HttpAccountError;
+use crate::AppState;
+
+#[post("/{nr}/close")]
+pub async fn route(info: web::Path<String>, data: web::Data<AppState>) -> Result<impl Responder> {
+    let nr = info.into_inner();
+
+    info!("closing account {}...", nr);
+
+    let bank = data.bank.read().unwrap();
+    match Bank::account_action(bank, &nr, |account| {
+        // TODO: make the error handling part of the passivate method
+        if account.balance > 0_f64 {
+            Err(AccountError::AccountNotZero)
+        } else if account.passivate() {
+            Ok(0_f64)
+        } else {
+            Err(AccountError::Inactive)
+        }
+    }) {
+        Err(e) => Err(HttpAccountError(e).into()),
+        Ok(_) => Ok(HttpResponse::Ok().finish()),
+    }
+}

http-server/src/handlers/create_account.rs

@@ -0,0 +1,29 @@
+use actix_web::{post, web, Responder, Result};
+use serde::{Deserialize, Serialize};
+
+use crate::AppState;
+
+#[derive(Serialize, Deserialize)]
+pub struct OwnerData {
+    pub(crate) owner: String,
+}
+
+#[derive(Serialize)]
+struct AccountCreated {
+    nr: String,
+}
+
+#[post("")]
+pub async fn route(
+    form: web::Form<OwnerData>,
+    data: web::Data<AppState>,
+) -> Result<impl Responder> {
+    let owner = &form.owner;
+    info!("creating new account with owner {}...", owner);
+
+    let mut bank = data.bank.write().unwrap();
+    let nr = bank.create_account(owner.clone());
+    info!("created account {}", nr);
+
+    Ok(web::Json(AccountCreated { nr }))
+}

http-server/src/handlers/deposit.rs

@@ -0,0 +1,31 @@
+use actix_web::{post, web, HttpResponse, Responder, Result};
+use serde::Serialize;
+
+use bank::bank::Bank;
+
+use crate::handlers::error::HttpAccountError;
+use crate::handlers::AmountData;
+use crate::AppState;
+
+#[derive(Serialize)]
+struct AccountCreated {
+    nr: String,
+}
+
+#[post("/{nr}/deposit")]
+pub async fn route(
+    info: web::Path<String>,
+    form: web::Form<AmountData>,
+    data: web::Data<AppState>,
+) -> Result<impl Responder> {
+    let nr = info.into_inner();
+    let amount = form.amount;
+
+    info!("depositing {} into account {}...", amount, nr);
+
+    let bank = data.bank.read().unwrap();
+    match Bank::account_action(bank, &nr, |account| account.deposit(amount)) {
+        Err(e) => Err(HttpAccountError(e).into()),
+        Ok(_) => Ok(HttpResponse::Ok().finish()),
+    }
+}

http-server/src/handlers/error.rs

@@ -0,0 +1,53 @@
+use std::fmt::{Display, Formatter};
+use std::ops::Deref;
+
+use actix_web::http::StatusCode;
+use actix_web::{HttpResponse, ResponseError};
+use serde::Serialize;
+use thiserror::Error;
+
+use bank::account::AccountError;
+
+#[derive(Serialize)]
+struct ErrorResponse {
+    code: u16,
+    message: String,
+}
+
+#[derive(Debug, Error)]
+pub struct HttpAccountError(pub AccountError);
+
+impl Display for HttpAccountError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.deref())
+    }
+}
+
+impl Deref for HttpAccountError {
+    type Target = AccountError;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl ResponseError for HttpAccountError {
+    fn status_code(&self) -> StatusCode {
+        match self.deref() {
+            AccountError::NotFound => StatusCode::NOT_FOUND,
+            AccountError::InvalidAmount => StatusCode::BAD_REQUEST,
+            AccountError::Inactive => StatusCode::BAD_REQUEST,
+            AccountError::Overdraw => StatusCode::BAD_REQUEST,
+            AccountError::AccountNotZero => StatusCode::EXPECTATION_FAILED,
+        }
+    }
+
+    fn error_response(&self) -> HttpResponse {
+        let status_code = self.status_code();
+        let error_response = ErrorResponse {
+            code: status_code.as_u16(),
+            message: self.to_string(),
+        };
+        HttpResponse::build(status_code).json(error_response)
+    }
+}

http-server/src/handlers/get_account.rs

@@ -0,0 +1,44 @@
+use std::ops::Deref;
+
+use actix_web::{get, web, Responder, Result};
+use serde::Serialize;
+
+use bank::account::{Account, AccountError};
+
+use crate::handlers::error::HttpAccountError;
+use crate::AppState;
+
+#[derive(Serialize)]
+pub struct JsonAccount {
+    pub number: String,
+    pub owner: String,
+    pub balance: f64,
+    pub is_active: bool,
+}
+
+impl From<&Account> for JsonAccount {
+    fn from(a: &Account) -> Self {
+        JsonAccount {
+            number: a.number.clone(),
+            owner: a.owner.clone(),
+            balance: a.balance,
+            is_active: a.is_active,
+        }
+    }
+}
+
+#[get("/{nr}")]
+pub async fn route(info: web::Path<String>, data: web::Data<AppState>) -> Result<impl Responder> {
+    let nr = info.into_inner();
+    info!("getting account {}...", nr);
+
+    let bank = data.bank.read().unwrap();
+    match bank.accounts.get(&nr) {
+        None => Err(HttpAccountError(AccountError::NotFound).into()),
+        Some(account) => {
+            let account = account.read().unwrap();
+            let account: JsonAccount = account.deref().into();
+            Ok(web::Json(account))
+        }
+    }
+}

http-server/src/handlers/get_account_nrs.rs

@@ -0,0 +1,11 @@
+use actix_web::{get, web, Responder, Result};
+
+use crate::AppState;
+
+#[get("")]
+pub async fn route(data: web::Data<AppState>) -> Result<impl Responder> {
+    info!("getting account numbers...");
+
+    let bank = data.bank.read().unwrap();
+    Ok(web::Json(bank.account_numbers()))
+}

http-server/src/handlers/mod.rs

@@ -0,0 +1,16 @@
+use serde::{Deserialize, Serialize};
+
+pub mod close_account;
+pub mod create_account;
+pub mod deposit;
+pub mod error;
+pub mod get_account;
+pub mod get_account_nrs;
+pub mod pong;
+pub mod transfer;
+pub mod withdraw;
+
+#[derive(Deserialize, Serialize)]
+pub struct AmountData {
+    pub(crate) amount: f64,
+}

http-server/src/handlers/pong.rs

@@ -0,0 +1,6 @@
+use actix_web::{get, HttpResponse};
+
+#[get("/ping")]
+pub async fn route() -> HttpResponse {
+    HttpResponse::Ok().finish()
+}

http-server/src/handlers/transfer.rs

@@ -0,0 +1,44 @@
+use actix_web::{post, web, HttpResponse, Responder, Result};
+use serde::{Deserialize, Serialize};
+
+use bank::account::AccountError;
+
+use crate::handlers::error::HttpAccountError;
+use crate::AppState;
+
+#[derive(Deserialize, Serialize)]
+pub struct TransferData {
+    pub(crate) from: String,
+    pub(crate) to: String,
+    pub(crate) amount: f64,
+}
+
+#[post("/transfer")]
+pub async fn route(
+    form: web::Form<TransferData>,
+    data: web::Data<AppState>,
+) -> Result<impl Responder> {
+    let from = form.from.clone();
+    let to = form.to.clone();
+    let amount = form.amount;
+
+    info!("transfering {} from {} to {}...", from, to, amount);
+
+    let bank = data.bank.read().unwrap();
+    let from_acc = bank
+        .accounts
+        .get(&from)
+        .ok_or(HttpAccountError(AccountError::NotFound))?;
+    let mut from_acc = from_acc.write().unwrap();
+
+    let to_acc = bank
+        .accounts
+        .get(&to)
+        .ok_or(HttpAccountError(AccountError::NotFound))?;
+    let mut to_acc = to_acc.write().unwrap();
+
+    match bank.transfer(&mut from_acc, &mut to_acc, amount) {
+        Err(e) => Err(HttpAccountError(e).into()),
+        Ok(_) => Ok(HttpResponse::Ok().finish()),
+    }
+}

http-server/src/handlers/withdraw.rs

@@ -0,0 +1,31 @@
+use actix_web::{post, web, HttpResponse, Responder, Result};
+use serde::Serialize;
+
+use bank::bank::Bank;
+
+use crate::handlers::error::HttpAccountError;
+use crate::handlers::AmountData;
+use crate::AppState;
+
+#[derive(Serialize)]
+struct AccountCreated {
+    nr: String,
+}
+
+#[post("/{nr}/withdraw")]
+pub async fn route(
+    info: web::Path<String>,
+    form: web::Form<AmountData>,
+    data: web::Data<AppState>,
+) -> Result<impl Responder> {
+    let nr = info.into_inner();
+    let amount = form.amount;
+
+    info!("withdrawing {} from account {}...", amount, nr);
+
+    let bank = data.bank.read().unwrap();
+    match Bank::account_action(bank, &nr, |account| account.withdraw(amount)) {
+        Err(e) => Err(HttpAccountError(e).into()),
+        Ok(_) => Ok(HttpResponse::Ok().finish()),
+    }
+}

http-server/src/main.rs

@@ -0,0 +1,204 @@
+#[macro_use]
+extern crate log;
+
+use std::sync::RwLock;
+
+use actix_web::middleware::TrailingSlash;
+use actix_web::web::{Data, ServiceConfig};
+use actix_web::{middleware, web, App, HttpServer};
+
+use bank::bank::Bank;
+
+use crate::handlers::close_account;
+use crate::handlers::create_account;
+use crate::handlers::deposit;
+use crate::handlers::get_account;
+use crate::handlers::get_account_nrs;
+use crate::handlers::pong;
+use crate::handlers::transfer;
+use crate::handlers::withdraw;
+
+pub struct AppState {
+    bank: RwLock<Bank>,
+}
+
+mod handlers;
+
+fn config_app(app_data: Data<AppState>) -> Box<dyn Fn(&mut ServiceConfig)> {
+    Box::new(move |cfg: &mut ServiceConfig| {
+        cfg.app_data(app_data.clone()).service(pong::route).service(
+            web::scope("/accounts")
+                .service(create_account::route)
+                .service(get_account::route)
+                .service(deposit::route)
+                .service(close_account::route)
+                .service(get_account_nrs::route)
+                .service(withdraw::route)
+                .service(transfer::route),
+        );
+    })
+}
+
+#[actix_web::main]
+async fn main() -> std::io::Result<()> {
+    pretty_env_logger::init();
+
+    let app_data = web::Data::new(AppState {
+        bank: RwLock::new(Bank::new()),
+    });
+
+    HttpServer::new(move || {
+        App::new()
+            .wrap(middleware::NormalizePath::new(TrailingSlash::Trim))
+            .configure(config_app(app_data.clone()))
+    })
+    .bind(("127.0.0.1", 8080))?
+    .run()
+    .await
+}
+
+#[cfg(test)]
+mod tests {
+    use actix_web::body::to_bytes;
+    use actix_web::{test, App};
+    use serde_json::Value;
+
+    use crate::create_account::OwnerData;
+    use crate::handlers::AmountData;
+    use crate::transfer::TransferData;
+
+    use super::*;
+
+    #[actix_web::test]
+    async fn test_routes() {
+        // TODO: split up into separate tests
+
+        let app_data = web::Data::new(AppState {
+            bank: RwLock::new(Bank::new()),
+        });
+
+        let app = test::init_service(
+            App::new()
+                .wrap(middleware::NormalizePath::new(TrailingSlash::Trim))
+                .configure(config_app(app_data)),
+        )
+        .await;
+
+        let payload = OwnerData {
+            owner: "aaa".to_string(),
+        };
+        let req = test::TestRequest::post()
+            .uri("/accounts")
+            .set_form(&payload)
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let body_bytes = to_bytes(resp.into_body()).await.unwrap();
+        let response_json: Value = serde_json::from_slice(&body_bytes).unwrap();
+        let nr = response_json["nr"].as_str().unwrap();
+
+        assert!(!nr.is_empty());
+
+        let payload = AmountData { amount: 10_f64 };
+        let req = test::TestRequest::post()
+            .uri(&format!("/accounts/{}/withdraw", nr))
+            .set_form(&payload)
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(!resp.status().is_success());
+
+        let req = test::TestRequest::post()
+            .uri(&format!("/accounts/{}/deposit", nr))
+            .set_form(&payload)
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let req = test::TestRequest::get()
+            .uri(&format!("/accounts/{}", nr))
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let body_bytes = to_bytes(resp.into_body()).await.unwrap();
+        let response_json: Value = serde_json::from_slice(&body_bytes).unwrap();
+        let balance = response_json["balance"].as_f64().unwrap();
+        assert_eq!(10_f64, balance);
+
+        let payload = OwnerData {
+            owner: "bbb".to_string(),
+        };
+        let req = test::TestRequest::post()
+            .uri("/accounts")
+            .set_form(&payload)
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let body_bytes = to_bytes(resp.into_body()).await.unwrap();
+        let response_json: Value = serde_json::from_slice(&body_bytes).unwrap();
+        let nr2 = response_json["nr"].as_str().unwrap();
+
+        let payload = TransferData {
+            from: nr.to_string(),
+            to: nr2.to_string(),
+            amount: 5_f64,
+        };
+        let req = test::TestRequest::post()
+            .uri("/accounts/transfer")
+            .set_form(&payload)
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let req = test::TestRequest::get()
+            .uri(&format!("/accounts/{}", nr2))
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let body_bytes = to_bytes(resp.into_body()).await.unwrap();
+        let response_json: Value = serde_json::from_slice(&body_bytes).unwrap();
+        let balance = response_json["balance"].as_f64().unwrap();
+        assert_eq!(5_f64, balance);
+
+        let req = test::TestRequest::post()
+            .uri(&format!("/accounts/{}/close", nr))
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(!resp.status().is_success());
+
+        let payload = AmountData { amount: 5_f64 };
+        let req = test::TestRequest::post()
+            .uri(&format!("/accounts/{}/withdraw", nr))
+            .set_form(&payload)
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let req = test::TestRequest::get().uri("/accounts").to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let body_bytes = to_bytes(resp.into_body()).await.unwrap();
+        let response_json: Value = serde_json::from_slice(&body_bytes).unwrap();
+        let nrs = response_json.as_array().unwrap();
+        assert_eq!(2, nrs.len());
+
+        let req = test::TestRequest::post()
+            .uri(&format!("/accounts/{}/close", nr))
+            .to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let req = test::TestRequest::get().uri("/accounts").to_request();
+        let resp = test::call_service(&app, req).await;
+        assert!(resp.status().is_success());
+
+        let body_bytes = to_bytes(resp.into_body()).await.unwrap();
+        let response_json: Value = serde_json::from_slice(&body_bytes).unwrap();
+        let nrs = response_json.as_array().unwrap();
+        assert_eq!(1, nrs.len());
+    }
+}

socket-server/Cargo.toml

@@ -8,3 +8,4 @@ bank = { path = "../bank" }
 anyhow = "1.0.55"
 log = "0.4.14"
 pretty_env_logger = "0.4.0"
+thiserror = "1.0.30"

socket-server/src/commands/close_account.rs

@@ -12,7 +12,12 @@ use crate::protocol;
 pub struct CloseAccount;
 
 impl Command for CloseAccount {
-    fn execute(&self, bank: Arc<RwLock<Bank>>, data: &[u8], mut stream: &TcpStream) -> Result<usize> {
+    fn execute(
+        &self,
+        bank: Arc<RwLock<Bank>>,
+        data: &[u8],
+        mut stream: &TcpStream,
+    ) -> Result<usize> {
         debug!("account nr bytes {:?}", data);
 
         let nr = String::from_utf8_lossy(data).to_string();
@@ -25,7 +30,7 @@ impl Command for CloseAccount {
                 let mut acc = acc.write().unwrap();
                 stream.write(&protocol::account_passivate(acc.passivate()))?
             }
-            None => stream.write(&protocol::account_passivate(false))?
+            None => stream.write(&protocol::account_passivate(false))?,
         };
 
         Ok(written)

socket-server/src/commands/create_account.rs

@@ -12,7 +12,12 @@ use crate::protocol;
 pub struct CreateAccount;
 
 impl Command for CreateAccount {
-    fn execute(&self, bank: Arc<RwLock<Bank>>, data: &[u8], mut stream: &TcpStream) -> Result<usize> {
+    fn execute(
+        &self,
+        bank: Arc<RwLock<Bank>>,
+        data: &[u8],
+        mut stream: &TcpStream,
+    ) -> Result<usize> {
         debug!("owner nr bytes {:?}", data);
 
         let owner = String::from_utf8_lossy(data);

socket-server/src/commands/deposit.rs

@@ -12,7 +12,12 @@ use crate::protocol;
 pub struct Deposit;
 
 impl Command for Deposit {
-    fn execute(&self, bank: Arc<RwLock<Bank>>, data: &[u8], mut stream: &TcpStream) -> Result<usize> {
+    fn execute(
+        &self,
+        bank: Arc<RwLock<Bank>>,
+        data: &[u8],
+        mut stream: &TcpStream,
+    ) -> Result<usize> {
         let value_bytes: [u8; 8] = <[u8; 8]>::try_from(data[..8].to_vec().as_slice())?;
         debug!("value bytes {:?}", value_bytes);
 
@@ -30,7 +35,7 @@ impl Command for Deposit {
                 let mut acc = acc.write().unwrap();
                 stream.write(&protocol::deposit(acc.deposit(amount)))?
             }
-            None => stream.write(&protocol::error(2))?
+            None => stream.write(&protocol::error(2))?,
         };
 
         Ok(written)

socket-server/src/commands/error.rs

@@ -0,0 +1,35 @@
+use std::fmt::{Display, Formatter};
+use std::ops::Deref;
+
+use thiserror::Error;
+
+use bank::account::AccountError;
+
+#[derive(Debug, Error)]
+pub struct SocketAccountError(pub AccountError);
+
+impl Display for SocketAccountError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.deref())
+    }
+}
+
+impl Deref for SocketAccountError {
+    type Target = AccountError;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl From<SocketAccountError> for u8 {
+    fn from(e: SocketAccountError) -> Self {
+        match e.deref() {
+            AccountError::Overdraw => 11,
+            AccountError::Inactive => 12,
+            AccountError::InvalidAmount => 13,
+            AccountError::NotFound => 14,
+            AccountError::AccountNotZero => 15,
+        }
+    }
+}

socket-server/src/commands/fail.rs

@@ -12,7 +12,12 @@ use crate::protocol;
 pub struct Fail;
 
 impl Command for Fail {
-    fn execute(&self, _: Arc<RwLock<Bank>>, error_code: &[u8], mut stream: &TcpStream) -> Result<usize> {
+    fn execute(
+        &self,
+        _: Arc<RwLock<Bank>>,
+        error_code: &[u8],
+        mut stream: &TcpStream,
+    ) -> Result<usize> {
         error!("sending error code {}", error_code[0]);
         let written = stream.write(&protocol::error(error_code[0]))?;
         Ok(written)

socket-server/src/commands/get_account.rs

@@ -12,7 +12,12 @@ use crate::protocol;
 pub struct GetAccount;
 
 impl Command for GetAccount {
-    fn execute(&self, bank: Arc<RwLock<Bank>>, data: &[u8], mut stream: &TcpStream) -> Result<usize> {
+    fn execute(
+        &self,
+        bank: Arc<RwLock<Bank>>,
+        data: &[u8],
+        mut stream: &TcpStream,
+    ) -> Result<usize> {
         debug!("account nr bytes {:?}", data);
         let nr = String::from_utf8_lossy(data).to_string();
 
@@ -25,7 +30,7 @@ impl Command for GetAccount {
                 let acc = acc.read().unwrap();
                 stream.write(&protocol::account(&acc))?
             }
-            None => stream.write(&protocol::error(2))?
+            None => stream.write(&protocol::error(2))?,
         };
 
         Ok(written)

socket-server/src/commands/get_account_nrs.rs

@@ -16,9 +16,7 @@ impl Command for GetAccountNrs {
         info!("getting account numbers...");
 
         let bank = bank.read().unwrap();
-        let nrs: Vec<String> = bank.account_numbers()
-            .into_iter()
-            .collect();
+        let nrs: Vec<String> = bank.account_numbers().into_iter().collect();
 
         let written = stream.write(&protocol::account_nrs(&nrs))?;
 

socket-server/src/commands/mod.rs

@@ -4,7 +4,6 @@ use std::sync::{Arc, RwLock};
 
 use anyhow::Result;
 
-use bank::account::AccountError;
 use bank::bank::Bank;
 
 use crate::commands::close_account::CloseAccount;
@@ -16,13 +15,14 @@ use crate::commands::get_account_nrs::GetAccountNrs;
 use crate::commands::pong::Pong;
 use crate::commands::withdraw::Withdraw;
 
-mod pong;
-mod fail;
 mod close_account;
 mod create_account;
 mod deposit;
+pub mod error;
+mod fail;
 mod get_account;
 mod get_account_nrs;
+mod pong;
 mod withdraw;
 
 pub trait Command: Sync + Send {
@@ -33,26 +33,6 @@ pub struct Commands {
     cmds: HashMap<u8, Box<dyn Command>>,
 }
 
-struct WebAccountError(AccountError);
-
-impl From<&WebAccountError> for u8 {
-    fn from(error: &WebAccountError) -> Self {
-        match error.0 {
-            AccountError::Overdraw() => 11,
-            AccountError::Inactive() => 12,
-            AccountError::InvalidAmount() => 13,
-        }
-    }
-}
-
-pub fn error_to_code(error: &AccountError) -> u8 {
-    match error {
-        AccountError::Overdraw() => 11,
-        AccountError::Inactive() => 12,
-        AccountError::InvalidAmount() => 13,
-    }
-}
-
 impl Commands {
     pub fn new() -> Self {
         let mut cmds = HashMap::new();
@@ -64,15 +44,19 @@ impl Commands {
         cmds.insert(6_u8, Box::new(Deposit) as Box<dyn Command>);
         cmds.insert(7_u8, Box::new(Withdraw) as Box<dyn Command>);
 
-        Self {
-            cmds
-        }
+        Self { cmds }
     }
 
-    pub fn run(&self, bank: Arc<RwLock<Bank>>, cmd: u8, data: &[u8], stream: &TcpStream) -> Result<usize> {
+    pub fn run(
+        &self,
+        bank: Arc<RwLock<Bank>>,
+        cmd: u8,
+        data: &[u8],
+        stream: &TcpStream,
+    ) -> Result<usize> {
         match self.cmds.get(&cmd) {
             None => Fail.execute(bank, &[1_u8], stream),
-            Some(cmd) => cmd.execute(bank, data, stream)
+            Some(cmd) => cmd.execute(bank, data, stream),
         }
     }
 }

socket-server/src/commands/withdraw.rs

@@ -12,7 +12,12 @@ use crate::protocol;
 pub struct Withdraw;
 
 impl Command for Withdraw {
-    fn execute(&self, bank: Arc<RwLock<Bank>>, data: &[u8], mut stream: &TcpStream) -> Result<usize> {
+    fn execute(
+        &self,
+        bank: Arc<RwLock<Bank>>,
+        data: &[u8],
+        mut stream: &TcpStream,
+    ) -> Result<usize> {
         let value_bytes: [u8; 8] = <[u8; 8]>::try_from(data[..8].to_vec().as_slice())?;
         debug!("value bytes {:?}", value_bytes);
 
@@ -24,13 +29,12 @@ impl Command for Withdraw {
         info!("withdrawing {} from {}...", amount, nr);
 
         let bank = bank.read().unwrap();
-
         let written = match bank.accounts.get(&nr) {
             Some(acc) => {
                 let mut acc = acc.write().unwrap();
                 stream.write(&protocol::withdraw(acc.withdraw(amount)))?
             }
-            None => stream.write(&protocol::error(2))?
+            None => stream.write(&protocol::error(2))?,
         };
 
         Ok(written)

socket-server/src/main.rs

@@ -1,10 +1,10 @@
 #[macro_use]
 extern crate log;
 
+mod commands;
 mod protocol;
 mod server;
 mod threadpool;
-mod commands;
 
 fn main() {
     pretty_env_logger::init();

socket-server/src/protocol.rs

@@ -2,18 +2,11 @@ use anyhow::Result;
 
 use bank::account::{Account, AccountError};
 
-use crate::commands::error_to_code;
+use crate::commands::error::SocketAccountError;
 
 pub const START: [u8; 2] = [0xde, 0xad];
 pub const PONG: u8 = 0b0010_0000;
 
-fn to_error_code(error: anyhow::Error, default: u8) -> u8 {
-    match error.root_cause().downcast_ref::<AccountError>() {
-        Some(e) => error_to_code(e),
-        None => default,
-    }
-}
-
 pub fn account_nr(nr: &str) -> Vec<u8> {
     let mut response = vec![PONG];
     response.append(&mut nr.as_bytes().to_vec());
@@ -26,17 +19,17 @@ pub fn account_passivate(was_passivated: bool) -> Vec<u8> {
     vec![PONG | is_active_byte]
 }
 
-pub fn deposit(result: Result<()>) -> Vec<u8> {
+pub fn deposit(result: Result<f64, AccountError>) -> Vec<u8> {
     match result {
-        Err(e) => error(to_error_code(e, 10)).to_vec(),
-        Ok(_) => vec![PONG]
+        Err(e) => error(SocketAccountError(e).into()).to_vec(),
+        Ok(_) => vec![PONG],
     }
 }
 
-pub fn withdraw(result: Result<()>) -> Vec<u8> {
+pub fn withdraw(result: Result<f64, AccountError>) -> Vec<u8> {
     match result {
-        Err(e) => error(to_error_code(e, 10)).to_vec(),
-        Ok(_) => vec![PONG]
+        Err(e) => error(SocketAccountError(e).into()).to_vec(),
+        Ok(_) => vec![PONG],
     }
 }
 

socket-server/src/server.rs

@@ -33,7 +33,11 @@ pub fn run(host: &str, threads: usize) -> Result<()> {
     Ok(())
 }
 
-fn handle_connection(bank: Arc<RwLock<Bank>>, cmds: &Commands, mut stream: TcpStream) -> Result<()> {
+fn handle_connection(
+    bank: Arc<RwLock<Bank>>,
+    cmds: &Commands,
+    mut stream: TcpStream,
+) -> Result<()> {
     const BUF_SIZE: usize = 64;
 
     let mut data: Vec<u8> = vec![];
@@ -58,4 +62,3 @@ fn handle_connection(bank: Arc<RwLock<Bank>>, cmds: &Commands, mut stream: TcpSt
 
     Ok(())
 }
-

socket-server/src/threadpool.rs

@@ -1,5 +1,5 @@
-use std::sync::Arc;
 use std::sync::mpsc;
+use std::sync::Arc;
 use std::sync::Mutex;
 use std::thread;
 
@@ -33,8 +33,8 @@ impl ThreadPool {
     }
 
     pub fn execute<F>(&self, f: F)
-        where
-            F: FnOnce() + Send + 'static,
+    where
+        F: FnOnce() + Send + 'static,
     {
         let job = Box::new(f);