Improve the find_by! macro to allow multiple columns

src/models/blogs.rs

@@ -67,14 +67,7 @@ impl Blog {
             .expect("Couldn't load blogs ")
     }
 
-    pub fn find_by_name(conn: &PgConnection, name: String, instance_id: i32) -> Option<Blog> {
-        blogs::table.filter(blogs::actor_id.eq(name))
-            .filter(blogs::instance_id.eq(instance_id))
-            .limit(1)
-            .load::<Blog>(conn)
-            .expect("Error loading blog by name")
-            .into_iter().nth(0)
-    }
+    find_by!(blogs, find_by_name, ap_url as String, instance_id as i32);
 
     pub fn find_local(conn: &PgConnection, name: String) -> Option<Blog> {
         Blog::find_by_name(conn, name, Instance::local_id(conn))

src/models/comments.rs

@@ -49,7 +49,6 @@ pub struct NewComment {
 impl Comment {
     insert!(comments, NewComment);
     get!(comments);
-
     find_by!(comments, find_by_post, post_id as i32);
     find_by!(comments, find_by_ap_url, ap_url as String);
 

src/models/likes.rs

@@ -38,6 +38,7 @@ impl Like {
     insert!(likes, NewLike);
     get!(likes);
     find_by!(likes, find_by_ap_url, ap_url as String);
+    find_by!(likes, find_by_user_on_post, user_id as i32, post_id as i32);
 
     pub fn update_ap_url(&self, conn: &PgConnection) {
         if self.ap_url.len() == 0 {
@@ -47,15 +48,6 @@ impl Like {
         }
     }
 
-    pub fn find_by_user_on_post(conn: &PgConnection, user: &User, post: &Post) -> Option<Like> {
-        likes::table.filter(likes::post_id.eq(post.id))
-            .filter(likes::user_id.eq(user.id))
-            .limit(1)
-            .load::<Like>(conn)
-            .expect("Error loading like for user and post")
-            .into_iter().nth(0)
-    }
-
     pub fn delete(&self, conn: &PgConnection) -> activity::Undo {
         diesel::delete(self).execute(conn).unwrap();
 

src/models/mod.rs

@@ -1,9 +1,9 @@
-// TODO: support multiple columns (see Like::find_by_user_on_post)
 macro_rules! find_by {
-    ($table:ident, $fn:ident, $col:ident as $type:ident) => {
+    ($table:ident, $fn:ident, $($col:ident as $type:ident),+) => {
         /// Try to find a $table with a given $col
-        pub fn $fn(conn: &PgConnection, val: $type) -> Option<Self> {
-            $table::table.filter($table::$col.eq(val))
+        pub fn $fn(conn: &PgConnection, $($col: $type),+) -> Option<Self> {
+            $table::table
+                $(.filter($table::$col.eq($col)))+
                 .limit(1)
                 .load::<Self>(conn)
                 .expect("Error loading $table by $col")

src/models/posts.rs

@@ -52,6 +52,8 @@ pub struct NewPost {
 impl Post {
     insert!(posts, NewPost);
     get!(posts);
+    find_by!(posts, find_by_slug, slug as String);
+    find_by!(posts, find_by_ap_url, ap_url as String);
 
     pub fn count_local(conn: &PgConnection) -> usize {
         use schema::post_authors;
@@ -64,9 +66,6 @@ impl Post {
             .len()
     }
 
-    find_by!(posts, find_by_slug, slug as String);
-    find_by!(posts, find_by_ap_url, ap_url as String);
-
     pub fn get_recents(conn: &PgConnection, limit: i64) -> Vec<Post> {
         posts::table.order(posts::creation_date.desc())
             .limit(limit)

src/models/reshares.rs

@@ -26,6 +26,8 @@ pub struct NewReshare {
 impl Reshare {
     insert!(reshares, NewReshare);
     get!(reshares);
+    find_by!(reshares, find_by_ap_url, ap_url as String);
+    find_by!(reshares, find_by_user_on_post, user_id as i32, post_id as i32);
 
     pub fn update_ap_url(&self, conn: &PgConnection) {
         if self.ap_url.len() == 0 {
@@ -39,17 +41,6 @@ impl Reshare {
         }
     }
 
-    find_by!(reshares, find_by_ap_url, ap_url as String);
-
-    pub fn find_by_user_on_post(conn: &PgConnection, user: &User, post: &Post) -> Option<Reshare> {
-        reshares::table.filter(reshares::post_id.eq(post.id))
-            .filter(reshares::user_id.eq(user.id))
-            .limit(1)
-            .load::<Reshare>(conn)
-            .expect("Error loading reshare for user and post")
-            .into_iter().nth(0)
-    }
-
     pub fn get_recents_for_author(conn: &PgConnection, user: &User, limit: i64) -> Vec<Reshare> {
         reshares::table.filter(reshares::user_id.eq(user.id))
             .order(reshares::creation_date.desc())

src/models/users.rs

@@ -115,15 +115,7 @@ impl User {
     }
 
     find_by!(users, find_by_email, email as String);
-
-    pub fn find_by_name(conn: &PgConnection, username: String, instance_id: i32) -> Option<User> {
-        users::table.filter(users::username.eq(username))
-            .filter(users::instance_id.eq(instance_id))
-            .limit(1)
-            .load::<User>(conn)
-            .expect("Error loading user by name")
-            .into_iter().nth(0)
-    }
+    find_by!(users, find_by_name, username as String, instance_id as i32);
 
     pub fn find_local(conn: &PgConnection, username: String) -> Option<User> {
         User::find_by_name(conn, username, Instance::local_id(conn))

src/routes/likes.rs

@@ -25,7 +25,7 @@ fn create(blog: String, slug: String, user: User, conn: DbConn) -> Redirect {
         likes::Like::notify(&*conn, like.into_activity(&*conn), user.clone().into_id());
         broadcast(&*conn, &user, like.into_activity(&*conn), user.get_followers(&*conn));
     } else {
-        let like = likes::Like::find_by_user_on_post(&*conn, &user, &post).unwrap();
+        let like = likes::Like::find_by_user_on_post(&*conn, user.id, post.id).unwrap();
         let delete_act = like.delete(&*conn);
         broadcast(&*conn, &user, delete_act, user.get_followers(&*conn));
     }

src/routes/reshares.rs

@@ -25,7 +25,7 @@ fn create(blog: String, slug: String, user: User, conn: DbConn) -> Redirect {
         Reshare::notify(&*conn, reshare.into_activity(&*conn), user.clone().into_id());
         broadcast(&*conn, &user, reshare.into_activity(&*conn), user.get_followers(&*conn));
     } else {
-        let reshare = Reshare::find_by_user_on_post(&*conn, &user, &post).unwrap();
+        let reshare = Reshare::find_by_user_on_post(&*conn, user.id, post.id).unwrap();
         let delete_act = reshare.delete(&*conn);
         broadcast(&*conn, &user, delete_act, user.get_followers(&*conn));
     }