put sql statements in separate files

src/decrease.sql

@@ -0,0 +1,14 @@
+UPDATE
+    food
+SET
+    actual_servings = MAX(
+        (SELECT
+            actual_servings
+            FROM
+                food
+            WHERE id = ?1) - 1,
+        0)
+WHERE
+    id = ?1
+RETURNING
+    actual_servings

src/get_food.sql

@@ -0,0 +1,12 @@
+SELECT
+    id,
+    portion,
+    name,
+    kc_per_serving,
+    target_servings,
+    actual_servings,
+    color
+FROM
+    food
+WHERE
+    id = ?1

src/get_foods.sql

@@ -0,0 +1,10 @@
+SELECT
+    id,
+    portion,
+    name,
+    kc_per_serving,
+    target_servings,
+    actual_servings,
+    color
+FROM
+    food

src/get_sum.sql

@@ -0,0 +1,4 @@
+SELECT
+    SUM(kc_per_serving * actual_servings) AS kc
+FROM
+    food

src/increase.sql

@@ -0,0 +1,9 @@
+UPDATE
+    food
+SET actual_servings = (
+    SELECT actual_servings
+    FROM food
+    WHERE id = ?1
+) + 1
+WHERE id = ?1
+RETURNING actual_servings

src/main.rs

@@ -9,7 +9,7 @@ use axum::{
     routing::{get, post},
 };
 use parking_lot::Mutex;
-use rusqlite::Connection;
+use rusqlite::{CachedStatement, Connection};
 use tower_http::trace::TraceLayer;
 use tower_request_id::{RequestId, RequestIdLayer};
 use tracing::{debug, error, info, info_span};
@@ -40,6 +40,53 @@ struct Food {
     color: String,
 }
 
+#[derive(Clone)]
+struct PreparedStatements {}
+
+impl<'conn> PreparedStatements {
+    fn check(conn: &Connection) -> rusqlite::Result<Self> {
+        conn.prepare_cached(include_str!("create_tables.sql"))?;
+        conn.prepare_cached(include_str!("increase.sql"))?;
+        conn.prepare_cached(include_str!("decrease.sql"))?;
+        conn.prepare_cached(include_str!("get_food.sql"))?;
+        conn.prepare_cached(include_str!("get_foods.sql"))?;
+        conn.prepare_cached(include_str!("get_sum.sql"))?;
+        Ok(PreparedStatements {})
+    }
+
+    fn create_tables(conn: &'conn Connection) -> CachedStatement<'conn> {
+        conn.prepare_cached(include_str!("create_tables.sql"))
+            .expect("cached statement is invalid")
+    }
+
+    fn increase(conn: &'conn Connection) -> CachedStatement<'conn> {
+        conn.prepare_cached(include_str!("increase.sql"))
+            .expect("cached statement is invalid")
+    }
+
+    fn decrease(conn: &'conn Connection) -> CachedStatement<'conn> {
+        conn.prepare_cached(include_str!("decrease.sql"))
+            .expect("cached statement is invalid")
+    }
+
+    fn get_food(conn: &'conn Connection) -> CachedStatement<'conn> {
+        conn.prepare_cached(include_str!("get_food.sql"))
+            .expect("cached statement is invalid")
+    }
+
+    fn get_foods(conn: &'conn Connection) -> CachedStatement<'conn> {
+        conn.prepare_cached(include_str!("get_foods.sql"))
+            .expect("cached statement is invalid")
+    }
+
+    fn get_sum(conn: &'conn Connection) -> CachedStatement<'conn> {
+        conn.prepare_cached(include_str!("get_sum.sql"))
+            .expect("cached statement is invalid")
+    }
+}
+
+type ConnState = Arc<Mutex<Connection>>;
+
 #[tokio::main]
 async fn main() -> Result<(), std::io::Error> {
     tracing_subscriber::registry()
@@ -60,11 +107,11 @@ async fn main() -> Result<(), std::io::Error> {
     let db_connecion_str = "./foods.db".to_string();
     debug!(db_connecion_str, "opening database");
     let conn = Connection::open(db_connecion_str).expect("failed to open database");
-    if let Err(e) = conn.execute(include_str!("create_tables.sql"), ()) {
+    PreparedStatements::check(&conn).expect("failed to prepare sql statements");
+    if let Err(e) = PreparedStatements::create_tables(&conn).execute(()) {
         error!(?e, "failed to create tables");
         panic!("failed to create tables: {:#?}", e);
     }
-    let conn = Arc::new(Mutex::new(conn));
 
     let app = Router::new()
         .route("/", get(root))
@@ -91,7 +138,7 @@ async fn main() -> Result<(), std::io::Error> {
             }),
         )
         .layer(RequestIdLayer)
-        .with_state(conn);
+        .with_state(Arc::new(Mutex::new(conn)));
 
     let address = "0.0.0.0:3001";
     let listener = tokio::net::TcpListener::bind(address)
@@ -106,13 +153,9 @@ async fn main() -> Result<(), std::io::Error> {
     axum::serve(listener, app).await
 }
 
-fn get_foods(conn: &Arc<Mutex<Connection>>) -> Vec<Food> {
+fn get_foods(conn: &ConnState) -> Vec<Food> {
     let conn = conn.lock();
-    let mut stmt = conn
+    let mut stmt = PreparedStatements::get_foods(&conn);
-        .prepare(
-            "SELECT id, portion, name, kc_per_serving, target_servings, actual_servings, color FROM food",
-        )
-        .unwrap();
     let foods: Vec<_> = stmt
         .query_map((), |row| {
             Ok(Food {
@@ -134,15 +177,13 @@ fn get_foods(conn: &Arc<Mutex<Connection>>) -> Vec<Food> {
 
 fn get_sum(conn: &Arc<Mutex<Connection>>) -> i32 {
     let conn = conn.lock();
-    let mut stmt = conn
+    let mut stmt = PreparedStatements::get_sum(&conn);
-        .prepare("SELECT SUM(kc_per_serving * actual_servings) as kc FROM food")
-        .unwrap();
     let sum = stmt.query_one((), |row| row.get(0)).unwrap();
     debug!(sum);
     sum
 }
 
-async fn root(State(conn): State<Arc<Mutex<Connection>>>) -> Html<String> {
+async fn root(State(conn): State<ConnState>) -> Html<String> {
     let foods = get_foods(&conn);
     let sum = get_sum(&conn);
     let index = IndexTemplate { foods, sum };
@@ -151,14 +192,14 @@ async fn root(State(conn): State<Arc<Mutex<Connection>>>) -> Html<String> {
 
 fn do_increase(conn: &Arc<Mutex<Connection>>, id: i32) {
     let conn = conn.lock();
-    let mut stmt = conn.prepare("UPDATE food SET actual_servings = (SELECT actual_servings FROM food WHERE id = ?1) + 1 WHERE id = ?1 RETURNING actual_servings").unwrap();
+    let mut stmt = PreparedStatements::increase(&conn);
     let new: i32 = stmt.query_one((id,), |row| row.get(0)).unwrap();
     debug!(id, new_serving_count = new, "increase");
 }
 
 fn get_food(conn: &Arc<Mutex<Connection>>, id: i32) -> Food {
     let conn = conn.lock();
-    let mut stmt = conn.prepare("SELECT id, portion, name, kc_per_serving, target_servings, actual_servings, color FROM food WHERE id = ?1").unwrap();
+    let mut stmt = PreparedStatements::get_food(&conn);
     let food = stmt
         .query_one((id,), |row| {
             Ok(Food {
@@ -186,7 +227,7 @@ async fn increase(State(conn): State<Arc<Mutex<Connection>>>, Path(id): Path<i32
 
 fn do_decrease(conn: &Arc<Mutex<Connection>>, id: i32) {
     let conn = conn.lock();
-    let mut stmt = conn.prepare("UPDATE food SET actual_servings = MAX((SELECT actual_servings FROM food WHERE id = ?1) - 1, 0) WHERE id = ?1 RETURNING actual_servings").unwrap();
+    let mut stmt = PreparedStatements::decrease(&conn);
     let new: i32 = stmt.query_one((id,), |row| row.get(0)).unwrap();
     debug!(id, new_serving_count = new, "decrease");
 }