feat: Add support for web framework poem@3

Support is gated behind the poem-3 feature.

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## [Unreleased]
 
 - Support `axum` v0.8 through `axum-core` v0.5
+- Add support for `poem` version 3 behind the `poem-3` feature.
 
 ## [0.26.0] - 2024-01-15
 

docs/content/web-frameworks.md

@@ -1,6 +1,6 @@
 # Web framework integration
 
-Maud includes support for these web frameworks: [Actix], [Rocket], [Rouille], [Tide] and [Axum].
+Maud includes support for these web frameworks: [Actix], [Rocket], [Rouille], [Tide], [Axum] and [Poem].
 
 [Actix]: https://actix.rs/
 [Rocket]: https://rocket.rs/
@@ -9,6 +9,7 @@ Maud includes support for these web frameworks: [Actix], [Rocket], [Rouille], [T
 [Axum]: https://docs.rs/axum/
 [Warp]: https://seanmonstar.com/blog/warp/
 [Submillisecond]: https://github.com/lunatic-solutions/submillisecond
+[Poem]: https://github.com/poem-web/poem
 
 # Actix
 
@@ -232,3 +233,38 @@ fn helloworld() -> Markup {
     }
 }
 ```
+
+# Poem
+
+Poem support is available with the "poem-3" feature:
+
+```toml
+# ...
+[dependencies]
+maud = { version = "*", features = ["poem-3"] }
+# ...
+```
+
+This adds an implementation of `poem::IntoResponse` for `Markup`/`PreEscaped<String>`.
+This then allows you to use it directly as a response!
+
+```rust,no_run
+use maud::{html, Markup};
+use poem::{get, handler, listener::TcpListener, Route, Server};
+
+#[handler]
+fn hello_world() -> Markup {
+    html! {
+        h1 { "Hello, World!" }
+    }
+}
+
+#[tokio::main]
+async fn main() -> Result<(), std::io::Error> {
+    let app = Route::new().at("/hello", get(hello_world));
+    Server::new(TcpListener::bind("0.0.0.0:3000"))
+        .name("hello-world")
+        .run(app)
+        .await
+}
+```

maud/Cargo.toml

@@ -18,6 +18,7 @@ default = []
 # Web framework integrations
 actix-web = ["actix-web-dep", "futures-util"]
 axum = ["axum-core", "http"]
+poem-3 = ["poem"]
 
 [dependencies]
 maud_macros = { version = "0.26.0", path = "../maud_macros" }
@@ -30,6 +31,7 @@ axum-core = { version = "0.5", optional = true }
 submillisecond = { version = "0.4.1", optional = true }
 http = { version = "1", optional = true }
 warp = { version = "0.3.6", optional = true }
+poem = { version = "3", optional = true }
 
 [dev-dependencies]
 trybuild = { version = "1.0.33", features = ["diff"] }

maud/src/lib.rs

@@ -359,6 +359,21 @@ mod tide_support {
     }
 }
 
+#[cfg(feature = "poem-3")]
+mod poem_3_support {
+    use crate::PreEscaped;
+    use alloc::string::String;
+    use poem::web::Html;
+    use poem::IntoResponse;
+    use poem::Response;
+
+    impl IntoResponse for PreEscaped<String> {
+        fn into_response(self) -> Response {
+            Html(self.into_string()).into_response()
+        }
+    }
+}
+
 #[cfg(feature = "axum")]
 mod axum_support {
     use crate::PreEscaped;