feat(db): add authority repository with multilingual labels

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

crates/db/src/authority.rs

@@ -0,0 +1,118 @@
+//! Authority records (person / organisation / place).
+
+use domain::{Authority, AuthorityId, AuthorityKind, AuthorityRef, LocalizedLabel, NewAuthority};
+use sqlx::Row;
+
+const LABELS_JSON: &str = "COALESCE(json_agg(json_build_object('lang', al.lang, 'label', al.label) \
+     ORDER BY al.lang) FILTER (WHERE al.authority_id IS NOT NULL), '[]'::json)";
+
+/// Insert an authority and its labels. Multiple statements — pass a transaction
+/// connection (`&mut *tx`) for atomicity.
+pub async fn create_authority(
+    conn: &mut sqlx::PgConnection,
+    new: &NewAuthority,
+) -> Result<AuthorityId, sqlx::Error> {
+    let id = AuthorityId::new();
+
+    sqlx::query("INSERT INTO authority (id, kind, external_uri) VALUES ($1, $2, $3)")
+        .bind(id.to_uuid())
+        .bind(new.kind.as_str())
+        .bind(new.external_uri.as_deref())
+        .execute(&mut *conn)
+        .await?;
+
+    for label in &new.labels {
+        sqlx::query("INSERT INTO authority_label (authority_id, lang, label) VALUES ($1, $2, $3)")
+            .bind(id.to_uuid())
+            .bind(&label.lang)
+            .bind(&label.label)
+            .execute(&mut *conn)
+            .await?;
+    }
+
+    Ok(id)
+}
+
+/// Fetch one authority (with its labels).
+pub async fn authority_by_id<'e, E>(
+    executor: E,
+    id: AuthorityId,
+) -> Result<Option<Authority>, sqlx::Error>
+where
+    E: sqlx::PgExecutor<'e>,
+{
+    let sql = format!(
+        "SELECT a.id, a.kind, a.external_uri, {LABELS_JSON} AS labels \
+         FROM authority a LEFT JOIN authority_label al ON al.authority_id = a.id \
+         WHERE a.id = $1 GROUP BY a.id"
+    );
+
+    let row = sqlx::query(&sql)
+        .bind(id.to_uuid())
+        .fetch_optional(executor)
+        .await?;
+
+    row.map(map_authority).transpose()
+}
+
+/// List authorities of a given kind (with labels), ordered by id.
+pub async fn list_by_kind<'e, E>(
+    executor: E,
+    kind: AuthorityKind,
+) -> Result<Vec<Authority>, sqlx::Error>
+where
+    E: sqlx::PgExecutor<'e>,
+{
+    let sql = format!(
+        "SELECT a.id, a.kind, a.external_uri, {LABELS_JSON} AS labels \
+         FROM authority a LEFT JOIN authority_label al ON al.authority_id = a.id \
+         WHERE a.kind = $1 GROUP BY a.id ORDER BY a.id"
+    );
+
+    let rows = sqlx::query(&sql)
+        .bind(kind.as_str())
+        .fetch_all(executor)
+        .await?;
+
+    rows.into_iter().map(map_authority).collect()
+}
+
+/// Resolve an authority to an [`AuthorityRef`] (carrying its kind).
+pub async fn resolve_authority<'e, E>(
+    executor: E,
+    id: AuthorityId,
+) -> Result<Option<AuthorityRef>, sqlx::Error>
+where
+    E: sqlx::PgExecutor<'e>,
+{
+    let kind: Option<String> = sqlx::query_scalar("SELECT kind FROM authority WHERE id = $1")
+        .bind(id.to_uuid())
+        .fetch_optional(executor)
+        .await?;
+
+    match kind {
+        Some(k) => {
+            let kind = AuthorityKind::from_db(&k).ok_or_else(|| {
+                sqlx::Error::Decode(format!("unknown authority kind: {k}").into())
+            })?;
+
+            Ok(Some(AuthorityRef::new(id, kind)))
+        }
+        None => Ok(None),
+    }
+}
+
+fn map_authority(row: sqlx::postgres::PgRow) -> Result<Authority, sqlx::Error> {
+    let kind_str: String = row.try_get("kind")?;
+    let kind = AuthorityKind::from_db(&kind_str)
+        .ok_or_else(|| sqlx::Error::Decode(format!("unknown authority kind: {kind_str}").into()))?;
+
+    let labels: sqlx::types::Json<Vec<LocalizedLabel>> = row.try_get("labels")?;
+
+    Ok(Authority {
+        id: AuthorityId::from_uuid(row.try_get("id")?),
+        kind,
+        external_uri: row.try_get("external_uri")?,
+        labels: labels.0,
+    })
+}