fix refreshing canteens when menu is empty

scraper/src/refresh.rs

@@ -119,7 +119,9 @@ pub async fn check_refresh(db: &sqlx::PgPool, date: NaiveDate, canteens: &[Cante
                     .difference(&db_dishes)
                     .collect::<HashSet<_>>();
 
-                if let Err(err) = update_stale_dishes(db, date, &stale_dishes, &new_dishes).await {
+                if let Err(err) =
+                    update_stale_dishes(db, date, &stale_dishes, &new_dishes, canteens).await
+                {
                     tracing::error!("Error updating stale dishes in db: {}", err);
                     false
                 } else {
@@ -151,32 +153,43 @@ async fn update_stale_dishes(
     date: NaiveDate,
     stale_dishes: &HashSet<&(Canteen, Dish)>,
     new_dishes: &HashSet<&(Canteen, Dish)>,
+    canteens: &[Canteen],
 ) -> Result<(), sqlx::Error> {
     let mut tx = db.begin().await?;
 
-    QueryBuilder::new("UPDATE meals SET is_latest = FALSE WHERE date = ")
+    if !stale_dishes.is_empty() {
-        .push_bind(date)
+        QueryBuilder::new("UPDATE meals SET is_latest = FALSE WHERE date = ")
-        .push(r#" AND ("name", canteen) IN "#)
+            .push_bind(date)
-        .push_tuples(stale_dishes, |mut sep, (canteen, dish)| {
+            .push(r#" AND ("name", canteen) IN "#)
-            sep.push_bind(&dish.name)
+            .push_tuples(stale_dishes, |mut sep, (canteen, dish)| {
-                .push_bind(canteen.get_identifier());
+                sep.push_bind(&dish.name)
-        })
+                    .push_bind(canteen.get_identifier());
-        .push(";")
+            })
-        .build()
+            .push(";")
-        .execute(&mut *tx)
+            .build()
-        .await?;
+            .execute(&mut *tx)
+            .await?;
+    }
 
     let chunks = new_dishes
         .iter()
         .sorted_by_key(|(c, _)| c)
         .chunk_by(|(c, _)| c);
 
-    let new_dishes_iter = chunks.into_iter().map(|(canteen, g)| {
+    let new_dishes_iter = chunks
-        (
+        .into_iter()
-            *canteen,
+        .map(|(canteen, g)| {
-            g.map(|(_, dish)| dish).cloned().collect::<Vec<_>>(),
+            (
-        )
+                *canteen,
-    });
+                g.map(|(_, dish)| dish).cloned().collect::<Vec<_>>(),
+            )
+        })
+        .chain(
+            canteens
+                .iter()
+                .map(|canteen| (*canteen, Vec::new()))
+                .unique_by(|(c, _)| *c),
+        );
 
     for (canteen, menu) in new_dishes_iter {
         add_menu_to_db(&mut tx, &date, canteen, menu).await?;

scraper/src/util.rs

@@ -85,35 +85,33 @@ pub async fn add_menu_to_db(
     canteen: Canteen,
     menu: Vec<Dish>,
 ) -> Result<(), sqlx::Error> {
-    if menu.is_empty() {
+    if !menu.is_empty() {
-        return Ok(());
+        let mut query = sqlx::QueryBuilder::new("INSERT INTO meals (date,canteen,name,dish_type,image_src,price_students,price_employees,price_guests,vegan,vegetarian,kjoules,proteins,carbohydrates,fats) ");
+
+        query
+            .push_values(menu, |mut sep, item| {
+                let vegan = item.is_vegan();
+
+                sep.push_bind(date)
+                    .push_bind(canteen.get_identifier())
+                    .push_bind(item.get_name().to_string())
+                    .push_bind(item.get_type() as DishType)
+                    .push_bind(item.get_image_src().map(str::to_string))
+                    .push_bind(item.get_price_students().to_owned())
+                    .push_bind(item.get_price_employees().to_owned())
+                    .push_bind(item.get_price_guests().to_owned())
+                    .push_bind(vegan)
+                    .push_bind(vegan || item.is_vegetarian())
+                    .push_bind(item.nutrition_values.kjoule)
+                    .push_bind(item.nutrition_values.protein.to_owned())
+                    .push_bind(item.nutrition_values.carbs.to_owned())
+                    .push_bind(item.nutrition_values.fat.to_owned());
+            })
+            .build()
+            .execute(&mut **db)
+            .await?;
     }
 
-    let mut query = sqlx::QueryBuilder::new("INSERT INTO meals (date,canteen,name,dish_type,image_src,price_students,price_employees,price_guests,vegan,vegetarian,kjoules,proteins,carbohydrates,fats) ");
-
-    query
-        .push_values(menu, |mut sep, item| {
-            let vegan = item.is_vegan();
-
-            sep.push_bind(date)
-                .push_bind(canteen.get_identifier())
-                .push_bind(item.get_name().to_string())
-                .push_bind(item.get_type() as DishType)
-                .push_bind(item.get_image_src().map(str::to_string))
-                .push_bind(item.get_price_students().to_owned())
-                .push_bind(item.get_price_employees().to_owned())
-                .push_bind(item.get_price_guests().to_owned())
-                .push_bind(vegan)
-                .push_bind(vegan || item.is_vegetarian())
-                .push_bind(item.nutrition_values.kjoule)
-                .push_bind(item.nutrition_values.protein.to_owned())
-                .push_bind(item.nutrition_values.carbs.to_owned())
-                .push_bind(item.nutrition_values.fat.to_owned());
-        })
-        .build()
-        .execute(&mut **db)
-        .await?;
-
     sqlx::query!(
         "INSERT INTO canteens_scraped (scraped_for, canteen) VALUES ($1, $2)",
         date,