core: Add meta_subjects to handle redirects

acrate-core/migrations/2024-11-14-031744_meta/down.sql

@@ -3,3 +3,4 @@ DROP TABLE IF EXISTS meta_link_properties CASCADE;
 DROP TABLE IF EXISTS meta_link_titles CASCADE;
 DROP TABLE IF EXISTS meta_links CASCADE;
 DROP TABLE IF EXISTS meta_aliases CASCADE;
+DROP TABLE IF EXISTS meta_subjects CASCADE;

acrate-core/migrations/2024-11-14-031744_meta/up.sql

@@ -1,3 +1,12 @@
+CREATE TABLE IF NOT EXISTS meta_subjects (
+	id UUID DEFAULT gen_random_uuid(),
+	document BPCHAR NOT NULL,
+	pattern BPCHAR NOT NULL,
+	redirect BPCHAR NOT NULL,
+
+	PRIMARY KEY (id)
+);
+
 CREATE TABLE IF NOT EXISTS meta_aliases (
 	id UUID DEFAULT gen_random_uuid(),
 	document BPCHAR NOT NULL,

acrate-core/src/meta.rs

@@ -4,6 +4,15 @@ use uuid::Uuid;
 use super::schema;
 
 
+#[derive(Debug, Queryable, QueryableByName, Identifiable, Selectable, Insertable)]
+#[diesel(table_name = schema::meta_subjects)]
+pub struct MetaSubject {
+	pub id: Uuid,
+	pub document: String,
+	pub pattern: String,
+	pub redirect: Option<String>,
+}
+
 #[derive(Debug, Queryable, QueryableByName, Identifiable, Selectable, Insertable)]
 #[diesel(table_name = schema::meta_aliases)]
 pub struct MetaAlias {
@@ -55,6 +64,24 @@ pub struct MetaProperty {
 	pub value: Option<String>,
 }
 
+impl MetaSubject {
+	pub async fn query_matching(conn: &mut AsyncPgConnection, doc: &str, subject: &str) -> QueryResult<Vec<MetaSubject>> {
+		use diesel::prelude::*;
+		use diesel_async::RunQueryDsl;
+		use schema::meta_subjects::dsl::*;
+		
+		let document_is_equal = document.eq(doc);
+		let subject_matches_pattern = subject.into_sql::<diesel::sql_types::Text>().ilike(pattern);
+		
+		meta_subjects
+			.filter(document_is_equal)
+			.filter(subject_matches_pattern)
+			.select(Self::as_select())
+			.load(conn)
+			.await
+	}
+}
+
 impl MetaAlias {
 	pub async fn query_matching(conn: &mut AsyncPgConnection, doc: &str, subject: &str) -> QueryResult<Vec<MetaAlias>> {
 		use diesel::prelude::*;

acrate-core/src/schema.rs

@@ -50,6 +50,15 @@ diesel::table! {
     }
 }
 
+diesel::table! {
+    meta_subjects (id) {
+        id -> Uuid,
+        document -> Bpchar,
+        pattern -> Bpchar,
+        redirect -> Bpchar,
+    }
+}
+
 diesel::joinable!(meta_link_properties -> meta_links (meta_link_id));
 diesel::joinable!(meta_link_titles -> meta_links (meta_link_id));
 
@@ -59,4 +68,5 @@ diesel::allow_tables_to_appear_in_same_query!(
     meta_link_titles,
     meta_links,
     meta_properties,
+    meta_subjects,
 );