doido_cable_macros/
lib.rs

1use proc_macro::TokenStream;
2use quote::quote;
3use syn::{parse_macro_input, ItemStruct};
4
5/// Marks a struct as a WebSocket channel.
6///
7/// Generates a [`doido_cable::ChannelName`] impl carrying the channel's
8/// registration name — its struct name (`ChatChannel`), which ActionCable uses
9/// in the `identifier` to route messages. The struct's own `Channel` impl
10/// (lifecycle + `received`) is written by the user and re-emitted untouched.
11#[proc_macro_attribute]
12pub fn channel(_attr: TokenStream, item: TokenStream) -> TokenStream {
13    let input = parse_macro_input!(item as ItemStruct);
14    let ident = &input.ident;
15    let name = ident.to_string();
16
17    quote! {
18        #input
19
20        impl doido_cable::ChannelName for #ident {
21            fn channel_name() -> &'static str {
22                #name
23            }
24        }
25
26        impl #ident {
27            /// The channel's registration name (generated by `#[channel]`).
28            pub fn channel_name() -> &'static str {
29                #name
30            }
31
32            /// The default stream name for this channel (its registration name).
33            pub fn stream_name() -> &'static str {
34                #name
35            }
36        }
37    }
38    .into()
39}
doido_cable_macros/lib.rs

doido_cable_macros/
lib.rs
