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.

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()),
+    }
+}