add MessageFilterExt

src/dispatching2/message_filter_ext.rs

@@ -0,0 +1,63 @@
+use dptree::{di::DependencyMap, Handler};
+use futures::Future;
+use std::sync::Arc;
+use teloxide_core::{types, types::Message};
+
+macro_rules! define_ext {
+    ($ext_name:ident, $for_ty:ty => $( ($func:ident, $arg_ty:ty, $get_func:expr) ,)*) => {
+        pub trait $ext_name<Out> {
+            $( define_ext!(@filter_sign $func, $arg_ty); )*
+        }
+        impl<Out> $ext_name<Out> for $for_ty
+        where
+            Out: Send + Sync + 'static,
+        {
+            $( define_ext!(@filter_impl $for_ty, $func, $arg_ty, $get_func); )*
+        }
+    };
+    (@filter_sign $func:ident, $arg_ty:ty) => {
+        fn $func<F, Fut>(f: F) -> Handler<'static, DependencyMap, Out>
+        where
+            F: Fn(&$arg_ty) -> Fut + Send + Sync + 'static,
+            Fut: Future<Output = bool> + Send,
+        ;
+    };
+    (@filter_impl $for_ty:ty, $func:ident, $arg_ty:ty, $get_func:expr) => {
+        fn $func<F, Fut>(f: F) -> Handler<'static, DependencyMap, Out> where
+            F: Fn(&$arg_ty) -> Fut + Send + Sync + 'static,
+            Fut: Future<Output = bool> + Send,
+        {
+            let filter = Arc::new(f);
+            dptree::filter(move |mes: $for_ty| {
+                let filter = filter.clone();
+                async move {
+                    match $get_func(&mes) {
+                        Some(user) => filter(user).await,
+                        None => false,
+                    }
+                }
+            })
+        }
+    };
+}
+
+// May be expanded in the future.
+define_ext!(
+    MessageFilterExt, Message =>
+    (filter_from, types::User, Message::from),
+    (filter_animation, types::Animation, Message::animation),
+    (filter_audio, types::Audio, Message::audio),
+    (filter_contact, types::Contact, Message::contact),
+    (filter_document, types::Document, Message::document),
+    (filter_location, types::Location, Message::location),
+    (filter_photo, [types::PhotoSize], Message::photo),
+    (filter_poll, types::Poll, Message::poll),
+    (filter_sticker, types::Sticker, Message::sticker),
+    (filter_text, str, Message::text),
+    (filter_reply_to_message, Message, Message::reply_to_message),
+    (filter_forward_from, types::ForwardedFrom, Message::forward_from),
+    (filter_new_chat_members, [types::User], Message::new_chat_members),
+    (filter_left_chat_member, types::User, Message::left_chat_member),
+    (filter_pinned, Message, Message::pinned_message),
+    (filter_dice, types::Dice, Message::dice),
+);

src/dispatching2/mod.rs

@@ -4,6 +4,7 @@ pub mod dialogue;
 mod dispatcher;
 mod handler_ext;
 mod handler_factory;
+mod message_filter_ext;
 
 pub use dispatcher::Dispatcher;
 pub use handler_ext::HandlerExt;