add fetch_one note

Cargo.lock

@@ -1376,6 +1376,7 @@ dependencies = [
  "dotenv",
  "log",
  "rand 0.8.3",
+ "rust_decimal",
  "serde",
  "serde_json",
  "simple_logger",

vtse-common/src/net.rs

@@ -1,4 +1,4 @@
-use crate::stock::Stock;
+use crate::{stock::Stock, user::User};
 use serde::Serialize;
 use uuid::Uuid;
 
@@ -10,11 +10,14 @@ pub enum ServerResponse {
     NewApiKey(Uuid),
     UserError(UserError),
     StockInfo(Stock),
+    UserInfo(User),
 }
 
 #[derive(Serialize)]
 pub enum UserError {
+    InvalidUsername,
     InvalidPassword,
     InvalidApiKey,
     NotAuthorized,
+    NotEnoughOwnedStock(usize),
 }

vtse-common/src/operations.rs

@@ -1,5 +1,3 @@
-use crate::stock::StockName;
-
 pub(crate) enum MarketOperation {
     Buy,
     Sell,

vtse-common/src/stock.rs

@@ -3,11 +3,8 @@ use serde::{Deserialize, Serialize};
 use std::str::FromStr;
 use thiserror::Error;
 
-#[derive(
-    Serialize, Deserialize, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Default, sqlx::Type,
-)]
+#[derive(Serialize, Deserialize, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Default)]
 #[serde(transparent)]
-#[sqlx(transparent)]
 pub struct StockName(String);
 
 impl From<String> for StockName {
@@ -37,6 +34,20 @@ impl From<String> for StockSymbol {
     }
 }
 
+impl FromStr for StockSymbol {
+    type Err = StockNameParseError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        Ok(Self(s.to_string()))
+    }
+}
+
+impl StockSymbol {
+    pub fn inner(&self) -> &str {
+        &self.0
+    }
+}
+
 #[derive(Serialize, Deserialize, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Default)]
 #[serde(transparent)]
 pub struct StockDescription(String);

vtse-common/src/user.rs

@@ -1,4 +1,6 @@
+use rust_decimal::Decimal;
 use serde::Deserialize;
+use serde::Serialize;
 use uuid::Uuid;
 
 #[derive(Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Default, Deserialize)]
@@ -10,7 +12,8 @@ impl ApiKey {
     }
 }
 
-#[derive(Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Default, Deserialize)]
+#[derive(Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Default, Deserialize, Serialize)]
+#[serde(transparent)]
 pub struct Username(String);
 
 impl Username {
@@ -20,6 +23,7 @@ impl Username {
 }
 
 #[derive(Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug, Default, Deserialize)]
+#[serde(transparent)]
 pub struct Password(String);
 
 impl Password {
@@ -27,3 +31,40 @@ impl Password {
         self.0.as_bytes()
     }
 }
+
+#[derive(Serialize)]
+#[serde(transparent)]
+pub struct UserBalance(Decimal);
+
+impl UserBalance {
+    pub fn new(decimal: Decimal) -> Self {
+        Self(decimal)
+    }
+}
+
+#[derive(Serialize)]
+#[serde(transparent)]
+pub struct UserDebt(Decimal);
+
+impl UserDebt {
+    pub fn new(decimal: Decimal) -> Self {
+        Self(decimal)
+    }
+}
+
+#[derive(Serialize)]
+pub struct User {
+    username: Username,
+    balance: UserBalance,
+    debt: UserDebt,
+}
+
+impl User {
+    pub fn new(username: Username, balance: UserBalance, debt: UserDebt) -> Self {
+        Self {
+            username,
+            balance,
+            debt,
+        }
+    }
+}

vtse-server/Cargo.toml

@@ -10,6 +10,7 @@ bytes = "1"
 dotenv = "0.15"
 log = "0.4"
 rand = "0.8"
+rust_decimal = "1.10.2"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 simple_logger = "1.11"

vtse-server/src/main.rs

@@ -36,12 +36,8 @@ async fn main() -> Result<()> {
         // clone simply clones the arc reference, so this is cheap.
         let db_pool = db_pool.clone();
         tokio::task::spawn(async {
-            match handle_stream(stream, db_pool).await {
-                Ok(_) => (),
-                Err(e) => {
-                    // stream.write_all(e);
-                    error!("{}", e);
-                }
+            if let Err(e) = handle_stream(stream, db_pool).await {
+                error!("{}", e);
             }
         });
     }
@@ -65,10 +61,11 @@ async fn handle_stream(mut socket: TcpStream, pool: PgPool) -> Result<()> {
         let data = buffer.split_to(bytes_read); // O(1)
         let parsed = serde_json::from_slice::<ServerOperation>(&data)?;
         debug!("Parsed operation: {:?}", parsed);
+
         let response = match parsed {
             ServerOperation::Query(op) => match op {
                 QueryOperation::StockInfo { stock } => state.stock_info(stock, &pool).await?,
-                QueryOperation::User(username) => state.user_info(username, &pool).await?,
+                QueryOperation::User { username } => state.user_info(username, &pool).await?,
             },
             ServerOperation::User(op) => match op {
                 UserOperation::Login { api_key } => state.login(api_key, &pool).await?,
@@ -80,8 +77,10 @@ async fn handle_stream(mut socket: TcpStream, pool: PgPool) -> Result<()> {
                 }
             },
             ServerOperation::Market(op) => match op {
-                MarketOperation::Buy(stock_name) => state.buy(stock_name, &pool)?,
-                MarketOperation::Sell(stock_name) => state.sell(stock_name, &pool)?,
+                MarketOperation::Buy { symbol, amount } => state.buy(symbol, amount, &pool).await?,
+                MarketOperation::Sell { symbol, amount } => {
+                    state.sell(symbol, amount, &pool).await?
+                }
             },
         };
 

vtse-server/src/operations.rs

@@ -1,5 +1,5 @@
 use serde::Deserialize;
-use vtse_common::stock::StockName;
+use vtse_common::stock::StockSymbol;
 use vtse_common::user::{ApiKey, Password, Username};
 
 #[derive(Deserialize, Debug, PartialEq)]
@@ -13,8 +13,8 @@ pub(crate) enum ServerOperation {
 #[derive(Deserialize, Debug, PartialEq)]
 #[serde(tag = "type", rename_all = "snake_case")]
 pub(crate) enum QueryOperation {
-    StockInfo { stock: StockName },
-    User(Username),
+    StockInfo { stock: StockSymbol },
+    User { username: Username },
 }
 
 #[derive(Deserialize, Debug, PartialEq)]
@@ -35,8 +35,8 @@ pub(crate) enum UserOperation {
 
 #[derive(Deserialize, Debug, PartialEq)]
 pub(crate) enum MarketOperation {
-    Buy(StockName),
-    Sell(StockName),
+    Buy { symbol: StockSymbol, amount: usize },
+    Sell { symbol: StockSymbol, amount: usize },
 }
 
 #[cfg(test)]
@@ -54,7 +54,7 @@ mod deserialize {
             }))
             .unwrap(),
             ServerOperation::Query(QueryOperation::StockInfo {
-                stock: StockName::from_str("Gura").unwrap()
+                stock: StockSymbol::from_str("Gura").unwrap()
             })
         )
     }
@@ -68,7 +68,7 @@ mod deserialize {
             }))
             .unwrap(),
             QueryOperation::StockInfo {
-                stock: StockName::from_str("Gura").unwrap()
+                stock: StockSymbol::from_str("Gura").unwrap()
             }
         )
     }

vtse-server/src/state.rs

@@ -1,11 +1,12 @@
 use crate::user::SaltedPassword;
+use rust_decimal::Decimal;
 use sodiumoxide::crypto::pwhash::argon2id13::{pwhash_verify, HashedPassword};
 use sqlx::{query, PgPool};
 use std::convert::TryFrom;
 use thiserror::Error;
 use vtse_common::net::{ServerResponse, UserError};
-use vtse_common::stock::{Stock, StockName};
-use vtse_common::user::{ApiKey, Password, Username};
+use vtse_common::stock::{Stock, StockSymbol};
+use vtse_common::user::{ApiKey, Password, User, UserBalance, UserDebt, Username};
 
 #[derive(Error, Debug)]
 pub(crate) enum StateError {
@@ -42,10 +43,14 @@ impl AppState {
 
 /// Query operations impl
 impl AppState {
-    pub(crate) async fn stock_info(&self, stock_name: StockName, pool: &PgPool) -> OperationResult {
+    pub(crate) async fn stock_info(
+        &self,
+        stock_symbol: StockSymbol,
+        pool: &PgPool,
+    ) -> OperationResult {
         let stock = query!(
-            "SELECT name, symbol, description, price FROM stocks WHERE name = $1",
-            stock_name as StockName
+            "SELECT name, symbol, description, price FROM stocks WHERE symbol = $1",
+            stock_symbol.inner()
         )
         .fetch_one(pool)
         .await?;
@@ -59,7 +64,21 @@ impl AppState {
     }
 
     pub(crate) async fn user_info(&self, username: Username, pool: &PgPool) -> OperationResult {
-        todo!()
+        let user = query!(
+            "SELECT balance, debt FROM users WHERE username = $1",
+            username.inner()
+        )
+        .fetch_optional(pool)
+        .await?;
+
+        match user {
+            Some(user) => Ok(ServerResponse::UserInfo(User::new(
+                username,
+                UserBalance::new(user.balance),
+                UserDebt::new(user.debt),
+            ))),
+            None => Ok(ServerResponse::UserError(UserError::InvalidUsername)),
+        }
     }
 }
 
@@ -175,18 +194,67 @@ impl AppState {
 
 /// Market operation implementation
 impl AppState {
-    pub(crate) fn buy(&self, stock_name: StockName, pool: &PgPool) -> OperationResult {
-        if !matches!(self, Self::Authorized{..}) {
-            return Err(StateError::WrongState);
+    pub(crate) async fn buy(
+        &self,
+        symbol: StockSymbol,
+        amount: usize,
+        pool: &PgPool,
+    ) -> OperationResult {
+        let id = *match self {
+            Self::Authorized { user_id } => user_id,
+            _ => return Err(StateError::WrongState),
+        };
+        let user_balance = Self::get_user_balance(id, pool).await?;
+
+        todo!()
+    }
+
+    pub(crate) async fn sell(
+        &self,
+        symbol: StockSymbol,
+        amount: usize,
+        pool: &PgPool,
+    ) -> OperationResult {
+        let id = *match self {
+            Self::Authorized { user_id } => user_id,
+            _ => return Err(StateError::WrongState),
+        };
+        let num_owned = Self::get_owned_stock_count(id, symbol, pool).await?;
+        if num_owned < amount {
+            return Ok(ServerResponse::UserError(UserError::NotEnoughOwnedStock(
+                num_owned,
+            )));
         }
         todo!()
     }
 
-    pub(crate) fn sell(&self, stock_name: StockName, pool: &PgPool) -> OperationResult {
-        if !matches!(self, Self::Authorized{..}) {
-            return Err(StateError::WrongState);
-        }
-        todo!()
+    // todo: fetch_one needs to turn into fetch_optional, else we can't discriminate user versus
+    // server error.
+
+    async fn get_user_balance(user_id: i32, pool: &PgPool) -> Result<Decimal, StateError> {
+        query!("SELECT balance FROM users where user_id = $1", user_id)
+            .fetch_one(pool)
+            .await
+            .map(|record| record.balance)
+            .map_err(StateError::from)
+    }
+
+    async fn get_owned_stock_count(
+        user_id: i32,
+        symbol: StockSymbol,
+        pool: &PgPool,
+    ) -> Result<usize, StateError> {
+        query!(
+            "SELECT amount FROM users_stocks
+            JOIN stocks ON users_stocks.stock_id = stocks.stock_id
+            WHERE user_id = $1 AND symbol = $2",
+            user_id,
+            symbol.inner()
+        )
+        .fetch_one(pool)
+        .await
+        .map(|record| record.amount as usize)
+        .map_err(StateError::from)
     }
 }
 

vtse-server/src/user.rs

@@ -1,7 +1,5 @@
-use sodiumoxide::crypto::pwhash::{
-    argon2id13::HashedPassword,
-    argon2id13::{pwhash, MEMLIMIT_INTERACTIVE, OPSLIMIT_INTERACTIVE},
-};
+use sodiumoxide::crypto::pwhash::argon2id13::HashedPassword;
+use sodiumoxide::crypto::pwhash::argon2id13::{pwhash, MEMLIMIT_INTERACTIVE, OPSLIMIT_INTERACTIVE};
 use std::convert::TryFrom;
 use vtse_common::user::Password;