Implement dialogue::enter

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
  - Implement `GetChatId` for `Update`.
+ - The `dialogue::enter()` function as a shortcut for `dptree::entry().enter_dialogue()`.
 
 ## 0.8.0 - 2022-04-18
 

examples/purchase.rs

@@ -13,7 +13,7 @@
 // ```
 
 use teloxide::{
-    dispatching::dialogue::{GetChatId, InMemStorage},
+    dispatching::dialogue::{self, GetChatId, InMemStorage},
     prelude::*,
     types::{InlineKeyboardButton, InlineKeyboardMarkup},
     utils::command::BotCommands,
@@ -53,8 +53,7 @@ async fn main() {
 
     Dispatcher::builder(
         bot,
-        dptree::entry()
-            .enter_dialogue::<Update, InMemStorage<State>, State>()
+        dialogue::enter::<Update, InMemStorage<State>, State, _>()
             .branch(
                 Update::filter_message()
                     .chain(teloxide::handler![State::ReceiveFullName].endpoint(receive_full_name)),

src/dispatching/dialogue/mod.rs

@@ -83,11 +83,14 @@ pub use crate::dispatching::dialogue::{RedisStorage, RedisStorageError};
 #[cfg(feature = "sqlite-storage")]
 pub use crate::dispatching::dialogue::{SqliteStorage, SqliteStorageError};
 
+use dptree::{prelude::DependencyMap, Handler};
 pub use get_chat_id::GetChatId;
 pub use storage::*;
 use teloxide_core::types::ChatId;
 
-use std::{marker::PhantomData, sync::Arc};
+use std::{fmt::Debug, marker::PhantomData, sync::Arc};
+
+use super::DpHandlerDescription;
 
 mod get_chat_id;
 mod storage;
@@ -180,6 +183,37 @@ where
     }
 }
 
+/// Enters a dialogue context.
+///
+/// A call to this function is the same as `dptree::entry().enter_dialogue()`.
+///
+/// See [`HandlerExt::enter_dialogue`].
+///
+/// [`HandlerExt::enter_dialogue`]: super::HandlerExt::enter_dialogue
+pub fn enter<Upd, S, D, Output>() -> Handler<'static, DependencyMap, Output, DpHandlerDescription>
+where
+    S: Storage<D> + ?Sized + Send + Sync + 'static,
+    <S as Storage<D>>::Error: Debug + Send,
+    D: Default + Send + Sync + 'static,
+    Upd: GetChatId + Clone + Send + Sync + 'static,
+    Output: Send + Sync + 'static,
+{
+    dptree::entry()
+        .chain(dptree::filter_map(|storage: Arc<S>, upd: Upd| {
+            let chat_id = upd.chat_id()?;
+            Some(Dialogue::new(storage, chat_id))
+        }))
+        .chain(dptree::filter_map_async(|dialogue: Dialogue<D, S>| async move {
+            match dialogue.get_or_default().await {
+                Ok(dialogue) => Some(dialogue),
+                Err(err) => {
+                    log::error!("dialogue.get_or_default() failed: {:?}", err);
+                    None
+                }
+            }
+        }))
+}
+
 /// Perform a dialogue FSM transition.
 ///
 /// This macro expands to a [`dptree::Handler`] that filters your dialogue

src/dispatching/handler_ext.rs

@@ -1,8 +1,6 @@
-use std::sync::Arc;
-
 use crate::{
     dispatching::{
-        dialogue::{Dialogue, GetChatId, Storage},
+        dialogue::{GetChatId, Storage},
         DpHandlerDescription,
     },
     types::{Me, Message},
@@ -82,19 +80,7 @@ where
         D: Default + Send + Sync + 'static,
         Upd: GetChatId + Clone + Send + Sync + 'static,
     {
-        self.chain(dptree::filter_map(|storage: Arc<S>, upd: Upd| {
-            let chat_id = upd.chat_id()?;
-            Some(Dialogue::new(storage, chat_id))
-        }))
-        .chain(dptree::filter_map_async(|dialogue: Dialogue<D, S>| async move {
-            match dialogue.get_or_default().await {
-                Ok(dialogue) => Some(dialogue),
-                Err(err) => {
-                    log::error!("dialogue.get_or_default() failed: {:?}", err);
-                    None
-                }
-            }
-        }))
+        self.chain(super::dialogue::enter::<Upd, S, D, Output>())
     }
 
     #[allow(deprecated)]