Show item class parents with breadcrumbs

.sqlx/query-85e1b1bae08c7edda9671214e6eeece6556236c25253a45c8ddc834751f72694.json

@@ -0,0 +1,28 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "SELECT item_classes.id, item_classes.name\n            FROM item_classes\n            JOIN unnest((SELECT parents FROM item_class_tree WHERE id = $1))\n                WITH ORDINALITY AS parents(id, n)\n                ON item_classes.id = parents.id\n            ORDER BY parents.n",
+  "describe": {
+    "columns": [
+      {
+        "ordinal": 0,
+        "name": "id",
+        "type_info": "Uuid"
+      },
+      {
+        "ordinal": 1,
+        "name": "name",
+        "type_info": "Varchar"
+      }
+    ],
+    "parameters": {
+      "Left": [
+        "Uuid"
+      ]
+    },
+    "nullable": [
+      false,
+      false
+    ]
+  },
+  "hash": "85e1b1bae08c7edda9671214e6eeece6556236c25253a45c8ddc834751f72694"
+}

src/database/item_classes/mod.rs

@@ -9,7 +9,7 @@ mod edit;
 mod list;
 mod show;
 
-use sqlx::PgPool;
+use sqlx::{query, PgPool};
 use uuid::Uuid;
 
 pub use add::{ItemClassAddForm, ItemClassAddFormPrefilled};
@@ -37,3 +37,20 @@ impl ItemClassPreview {
         Self { id, name }
     }
 }
+
+impl ItemClassRepository {
+    pub async fn parents(&self, id: Uuid) -> sqlx::Result<Vec<ItemClassPreview>> {
+        query!(
+            r#"SELECT item_classes.id, item_classes.name
+            FROM item_classes
+            JOIN unnest((SELECT parents FROM item_class_tree WHERE id = $1))
+                WITH ORDINALITY AS parents(id, n)
+                ON item_classes.id = parents.id
+            ORDER BY parents.n"#,
+            id
+        )
+        .map(|row| ItemClassPreview::new(row.id, row.name))
+        .fetch_all(&self.pool)
+        .await
+    }
+}

src/frontend/item_class/show.rs

@@ -4,7 +4,7 @@
 
 use actix_identity::Identity;
 use actix_web::{error, get, web, Responder};
-use maud::html;
+use maud::{html, Render};
 use uuid::Uuid;
 
 use crate::database::ItemClassRepository;
@@ -31,6 +31,11 @@ async fn get(
         .await
         .map_err(error::ErrorInternalServerError)?;
 
+    let parents = item_class_repo
+        .parents(id)
+        .await
+        .map_err(error::ErrorInternalServerError)?;
+
     let children = item_class_repo
         .children(id)
         .await
@@ -96,10 +101,14 @@ async fn get(
                     th { "Name" }
                     td { (item_class.name) }
                 }
-                @if let Some(parent) = item_class.parent {
                 tr {
-                        th { "Parent" }
-                        td { (parent) }
+                    th { "Parents" }
+                    td {
+                        (templates::helpers::parents_breadcrumb(
+                            &item_class.name,
+                            parents.iter().map(|parent| parent as &dyn Render).collect(),
+                            true
+                        ))
                     }
                 }
                 tr {