Add a API entry point to get all tags

backend/src/app.rs

@@ -155,8 +155,7 @@ pub fn make_service(
                 .post(services::ron::recipe::add_tags)
                 .delete(services::ron::recipe::rm_tags),
         )
-        // TODO
-        // .route("/recipe/tags".get(services::ron::recipe::get_all_tags))
+        .route("/recipe/tags", get(services::ron::recipe::get_all_tags))
         .route(
             "/recipe/{id}/difficulty",
             patch(services::ron::recipe::set_difficulty),

backend/src/data/db/recipe.rs

@@ -1,3 +1,5 @@
+use std::u32;
+
 use chrono::prelude::*;
 use common::ron_api::Difficulty;
 use itertools::Itertools;
@@ -380,29 +382,20 @@ WHERE [Recipe].[user_id] = $1
             .map_err(DBError::from)
     }
 
-    pub async fn get_all_tags(&self) -> Result<Vec<String>> {
+    pub async fn get_all_tags(&self, lang: &str, max_number: Option<u32>) -> Result<Vec<String>> {
         sqlx::query_scalar(
             r#"
-SELECT [name] FROM [Tag]
-ORDER BY [name]
-            "#,
-        )
-        .fetch_all(&self.pool)
-        .await
-        .map_err(DBError::from)
-    }
-
-    pub async fn get_all_tags_by_lang(&self, lang: &str) -> Result<Vec<String>> {
-        sqlx::query_scalar(
-            r#"
-SELECT DISTINCT [name] FROM [Tag]
-INNER JOIN [RecipeTag] ON [RecipeTag].[tag_id] = [Tag].[id]
-INNER JOIN [Recipe] ON [Recipe].[id] = [RecipeTag].[recipe_id]
+SELECT [name], COUNT([name]) as [nb_used] FROM [Tag]
+	INNER JOIN [RecipeTag] ON [RecipeTag].[tag_id] = [Tag].[id]
+	INNER JOIN [Recipe] ON [Recipe].[id] = [RecipeTag].[recipe_id]
 WHERE [Recipe].[lang] = $1
-ORDER BY [name]
+GROUP BY [Tag].[name]
+ORDER BY [nb_used] DESC, [name]
+LIMIT $2
             "#,
         )
         .bind(lang)
+        .bind(max_number.unwrap_or(u32::MAX))
         .fetch_all(&self.pool)
         .await
         .map_err(DBError::from)
@@ -1078,9 +1071,15 @@ VALUES
         assert_eq!(connection.get_recipes_tags(recipe_id_1).await?, tags_1);
         assert_eq!(connection.get_recipes_tags(recipe_id_2).await?, tags_2);
 
-        assert_eq!(connection.get_all_tags().await?, ["abc", "def", "xyz"]);
+        assert_eq!(
+            connection.get_all_tags("en", None).await?,
+            ["abc", "xyz", "def"]
+        );
         connection.rm_recipe_tags(recipe_id_2, &["abc"]).await?;
-        assert_eq!(connection.get_all_tags().await?, ["abc", "def", "xyz"]);
+        assert_eq!(
+            connection.get_all_tags("en", None).await?,
+            ["xyz", "abc", "def"] // Most used tags come first.
+        );
 
         assert_eq!(
             connection.get_recipes_tags(recipe_id_1).await?,
@@ -1098,13 +1097,12 @@ VALUES
             connection.get_recipes_tags(recipe_id_2).await?,
             ["def", "xyz"]
         );
-        assert_eq!(connection.get_all_tags().await?, ["def", "xyz"]);
-        assert_eq!(connection.get_all_tags_by_lang("en").await?, ["def", "xyz"]);
+        assert_eq!(connection.get_all_tags("en", None).await?, ["xyz", "def"]);
 
         connection.rm_recipe_tags(recipe_id_1, &tags_1).await?;
         connection.rm_recipe_tags(recipe_id_2, &tags_2).await?;
 
-        assert!(connection.get_all_tags().await?.is_empty());
+        assert!(connection.get_all_tags("en", None).await?.is_empty());
 
         Ok(())
     }

backend/src/services/ron/mod.rs

@@ -1,11 +1,10 @@
 use axum::{
     debug_handler,
-    extract::{Extension, Path, Query, State},
+    extract::{Extension, Path, State},
     http::{HeaderMap, StatusCode},
     response::{IntoResponse, Result},
 };
 use axum_extra::extract::cookie::{Cookie, CookieJar, SameSite};
-use common::ron_api;
 
 use crate::{
     app::Context,

backend/src/services/ron/recipe.rs

@@ -88,6 +88,19 @@ pub async fn get_tags(
     ))
 }
 
+#[debug_handler]
+pub async fn get_all_tags(
+    State(connection): State<db::Connection>,
+    Extension(context): Extension<Context>,
+    nb_max_tags: Query<Option<u32>>,
+    lang: Query<Option<String>>,
+) -> Result<impl IntoResponse> {
+    let lang = lang.0.unwrap_or(context.tr.current_lang_code().to_string());
+    Ok(ron_response_ok(
+        connection.get_all_tags(&lang, nb_max_tags.0).await?,
+    ))
+}
+
 #[debug_handler]
 pub async fn add_tags(
     State(connection): State<db::Connection>,