Handlers are _named operations_, which can be exposed via routes.

Each domain module that exposes handlers does so through a `handlers` child module, ideally as a top-level symbol that can be plugged directly into Axum's `MethodRouter`. Modules could make exceptions to this - kill the doctrinaire inside yourself, after all - but none of the API modules that actually exist need such exceptions, and consistency is useful.

The related details of request types, URL types, response types, errors, &c &c are then organized into modules under `handlers`, along with their respective tests.

1 files changed, 58 insertions, 0 deletions

diff --git a/src/ui/handlers/channel.rs b/src/ui/handlers/channel.rs
new file mode 100644
index 0000000..d3199dd
--- /dev/null
+++ b/src/ui/handlers/channel.rs
@@ -0,0 +1,58 @@
+use axum::{
+    extract::{Path, State},
+    response::{self, IntoResponse, Redirect},
+};
+
+use crate::{
+    app::App,
+    channel::{self, app},
+    error::Internal,
+    token::extract::Identity,
+    ui::{
+        assets::{Asset, Assets},
+        error::NotFound,
+    },
+};
+
+pub async fn handler(
+    State(app): State<App>,
+    identity: Option<Identity>,
+    Path(channel): Path<channel::Id>,
+) -> Result<Asset, Error> {
+    let _ = identity.ok_or(Error::NotLoggedIn)?;
+    app.channels().get(&channel).await.map_err(Error::from)?;
+
+    Assets::index().map_err(Error::Internal)
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error("channel not found")]
+    NotFound,
+    #[error("not logged in")]
+    NotLoggedIn,
+    #[error("{0}")]
+    Internal(Internal),
+}
+
+impl From<app::Error> for Error {
+    fn from(error: app::Error) -> Self {
+        match error {
+            app::Error::NotFound(_) | app::Error::Deleted(_) => Self::NotFound,
+            other => Self::Internal(other.into()),
+        }
+    }
+}
+
+impl IntoResponse for Error {
+    fn into_response(self) -> response::Response {
+        match self {
+            Self::NotFound => match Assets::index() {
+                Ok(asset) => NotFound(asset).into_response(),
+                Err(internal) => internal.into_response(),
+            },
+            Self::NotLoggedIn => Redirect::temporary("/login").into_response(),
+            Self::Internal(error) => error.into_response(),
+        }
+    }
+}