Injectable<DependencyMap, _, _>` is not satisfied when using trait objects

[fertkir]

When implementing by bot I'm trying to achieve 2 things:

1. My message handler should not depend on Teloxide. This is needed if I would like to add, for instance, a Discord/Whatsapp/YouNameIt bot support.
2. I don't want to pass all the dependencies through method calls, so I create a struct and call a handle() method on it.

As a result I have the following code:

use std::sync::Arc;

use teloxide::{Bot, dptree};
use teloxide::dispatching::{Dispatcher, UpdateFilterExt};
use teloxide::prelude::{Message, Update};

#[tokio::main]
async fn main() {
    let input_handler = Arc::new(InputHandler{});
    let handler = dptree::entry()
        .branch(Update::filter_message().endpoint(handle));
    Dispatcher::builder(Bot::from_env(), handler)
        .dependencies(dptree::deps![input_handler])
        .enable_ctrlc_handler()
        .build().dispatch().await;
}

async fn handle(input_handler: Arc<InputHandler>, bot: Bot, msg: Message) -> Result<(), String> {
    input_handler.handle(Box::new(CmdImpl{})).await
}

struct InputHandler {
}

trait Cmd {
}

struct CmdImpl {
}

impl Cmd for CmdImpl {
}

impl InputHandler {
    async fn handle(&self,
                    cmd: Box<dyn Cmd>, // this way it does not compile
                    // cmd: Box<CmdImpl>, // this way it compiles
    ) -> Result<(), String> {
        Ok(())
    }
}

If I use a trait object as a parameter for InputHandler.handle(), it doesn't compile with the following error:

error[E0277]: the trait bound `fn(Arc<InputHandler>, Bot, teloxide::prelude::Message) -> impl Future<Output = Result<(), String>> {handle}: Injectable<DependencyMap, _, _>` is not satisfied
   --> src/main.rs:11:51
    |
11  |         .branch(Update::filter_message().endpoint(handle));
    |                                          -------- ^^^^^^ the trait `Injectable<DependencyMap, _, _>` is not implemented for fn item `fn(Arc<InputHandler>, Bot, teloxide::prelude::Message) -> impl Future<Output = Result<(), String>> {handle}`
    |                                          |
    |                                          required by a bound introduced by this call
    |
    = help: the following other types implement trait `Injectable<Input, Output, FnArgs>`:
              <Asyncify<Func> as Injectable<Input, Output, ()>>
              <Asyncify<Func> as Injectable<Input, Output, (A,)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C, D)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C, D, E)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C, D, E, F)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C, D, E, F, G)>>
            and 2 others
note: required by a bound in `dptree::handler::methods::<impl Handler<'a, Input, Output, Descr>>::endpoint`
   --> /home/fertkir/.cargo/registry/src/index.crates.io-6f17d22bba15001f/dptree-0.3.0/src/handler/methods.rs:108:12
    |
106 |     pub fn endpoint<F, FnArgs>(self, f: F) -> Handler<'a, Input, Output, Descr>
    |            -------- required by a bound in this associated function
107 |     where
108 |         F: Injectable<Input, Output, FnArgs> + Send + Sync + 'a,
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `dptree::handler::methods::<impl Handler<'a, Input, Output, Descr>>::endpoint`

Could anyone please help?

[fertkir]

Made it Box<dyn Input + Send + Sync>, and it worked

[1500256797]

sir i also meet same error. but i still dont konw how to fix it . can you help me ?

   --> src/bin/trading_bot.rs:28:58
    |
28  |         .branch(Update::filter_callback_query().endpoint(inline_keyboard_callback_handler));
    |                                                 -------- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Injectable<DependencyMap, _, _>` is not implemented for fn item `fn(Bot, teloxide::prelude::CallbackQuery) -> impl Future<Output = Result<(), Box<(dyn std::error::Error + Send + Sync + 'static)>>> {inline_keyboard_callback_handler}`
    |                                                 |
    |                                                 required by a bound introduced by this call
    |
    = help: the following other types implement trait `Injectable<Input, Output, FnArgs>`:
              <Asyncify<Func> as Injectable<Input, Output, ()>>
              <Asyncify<Func> as Injectable<Input, Output, (A,)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C, D)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C, D, E)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C, D, E, F)>>
              <Asyncify<Func> as Injectable<Input, Output, (A, B, C, D, E, F, G)>>
            and 2 others
note: required by a bound in `dptree::handler::methods::<impl Handler<'a, Input, Output, Descr>>::endpoint`
   --> /Users/ouhuang/.cargo/registry/src/index.crates.io-6f17d22bba15001f/dptree-0.3.0/src/handler/methods.rs:108:12
    |
106 |     pub fn endpoint<F, FnArgs>(self, f: F) -> Handler<'a, Input, Output, Descr>
    |            -------- required by a bound in this associated function
107 |     where
108 |         F: Injectable<Input, Output, FnArgs> + Send + Sync + 'a,
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ required by this bound in `dptree::handler::methods::<impl Handler<'a, Input, Output, Descr>>::endpoint`

warning: unused import: `EditMessageReplyMarkupSetters`

here is my handler

 let handler = dptree::entry()
        .branch(Update::filter_message().endpoint(message_handler))
        .branch(Update::filter_callback_query().endpoint(inline_keyboard_callback_handler));

.......


async fn inline_keyboard_callback_handler(
    bot: Bot,
    q: CallbackQuery,
) -> Result<(), Box<(dyn std::error::Error + Send + Sync + 'static)>> {

[fertkir]

You haven't added your CallbackQuery to dependencies.
It isn't teloxide's struct, is it?