caps and delete

backend/src/auth/capability_guard.rs

@@ -0,0 +1,120 @@
+use std::sync::Arc;
+
+use axum::{
+    http::{Request, StatusCode},
+    response::IntoResponse,
+};
+use tower::{Layer, Service};
+
+use crate::{auth::AuthenticatedUser, error::AppError, models::ApiCapability};
+
+#[derive(Clone, Copy)]
+pub enum CapabilityStrategy {
+    All,
+    Any,
+}
+
+#[derive(Clone)]
+pub struct RequireCapabilitiesLayer {
+    required: Arc<Vec<ApiCapability>>,
+    strategy: CapabilityStrategy,
+}
+
+impl RequireCapabilitiesLayer {
+    pub fn all<I>(caps: I) -> Self
+    where
+        I: IntoIterator<Item = ApiCapability>,
+    {
+        Self {
+            required: Arc::new(caps.into_iter().collect()),
+            strategy: CapabilityStrategy::All,
+        }
+    }
+
+    pub fn any<I>(caps: I) -> Self
+    where
+        I: IntoIterator<Item = ApiCapability>,
+    {
+        Self {
+            required: Arc::new(caps.into_iter().collect()),
+            strategy: CapabilityStrategy::Any,
+        }
+    }
+}
+
+impl<S> Layer<S> for RequireCapabilitiesLayer {
+    type Service = RequireCapabilities<S>;
+
+    fn layer(&self, inner: S) -> Self::Service {
+        RequireCapabilities {
+            inner,
+            required: Arc::clone(&self.required),
+            strategy: self.strategy,
+        }
+    }
+}
+
+#[derive(Clone)]
+pub struct RequireCapabilities<S> {
+    inner: S,
+    required: Arc<Vec<ApiCapability>>,
+    strategy: CapabilityStrategy,
+}
+
+impl<S, B> Service<Request<B>> for RequireCapabilities<S>
+where
+    S: Service<Request<B>, Response = axum::response::Response> + Send,
+    S::Future: Send + 'static,
+    B: Send + 'static,
+{
+    type Response = S::Response;
+    type Error = S::Error;
+    type Future = std::pin::Pin<
+        Box<dyn std::future::Future<Output = Result<Self::Response, Self::Error>> + Send>,
+    >;
+
+    fn poll_ready(
+        &mut self,
+        cx: &mut std::task::Context<'_>,
+    ) -> std::task::Poll<Result<(), Self::Error>> {
+        self.inner.poll_ready(cx)
+    }
+
+    fn call(&mut self, req: Request<B>) -> Self::Future {
+        if self.required.is_empty() {
+            let fut = self.inner.call(req);
+            return Box::pin(async move { fut.await });
+        }
+
+        let (parts, body) = req.into_parts();
+        let user = match parts.extensions.get::<AuthenticatedUser>() {
+            Some(user) => user,
+            None => {
+                let response = AppError::unauthorized().into_response();
+                return Box::pin(async move { Ok(response) });
+            }
+        };
+
+        let allowed = match self.strategy {
+            CapabilityStrategy::All => self
+                .required
+                .iter()
+                .all(|cap| user.capabilities.contains(cap)),
+            CapabilityStrategy::Any => self
+                .required
+                .iter()
+                .any(|cap| user.capabilities.contains(cap)),
+        };
+
+        if !allowed {
+            let response = AppError::new(StatusCode::FORBIDDEN, "missing required capability")
+                .with_code("missing_capability")
+                .into_response();
+            return Box::pin(async move { Ok(response) });
+        }
+
+        let req = Request::from_parts(parts, body);
+        let fut = self.inner.call(req);
+        Box::pin(async move { fut.await })
+    }
+}