modo-rs 0.6.2

Rust web framework for small monolithic apps
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307

use std::future::Future;
use std::pin::Pin;
use std::sync::Arc;
use std::task::{Context, Poll};

use axum::body::Body;
use axum::response::IntoResponse;
use http::Request;
use tower::{Layer, Service};

use crate::Error;

use super::extractor::Role;

// --- require_role ---

/// Creates a guard layer that rejects requests unless the resolved role
/// matches ANY of the allowed roles. Returns 403 Forbidden if role is
/// present but not allowed, 401 Unauthorized if no role is present.
///
/// Apply with `.route_layer()` so the guard runs after route matching.
/// The RBAC middleware must be applied with `.layer()` on the outer router
/// so that [`Role`] is already in extensions when this guard runs.
pub fn require_role(roles: impl IntoIterator<Item = impl Into<String>>) -> RequireRoleLayer {
    RequireRoleLayer {
        roles: Arc::new(roles.into_iter().map(Into::into).collect()),
    }
}

/// Tower layer produced by [`require_role()`].
pub struct RequireRoleLayer {
    roles: Arc<Vec<String>>,
}

impl Clone for RequireRoleLayer {
    fn clone(&self) -> Self {
        Self {
            roles: self.roles.clone(),
        }
    }
}

impl<S> Layer<S> for RequireRoleLayer {
    type Service = RequireRoleService<S>;

    fn layer(&self, inner: S) -> Self::Service {
        RequireRoleService {
            inner,
            roles: self.roles.clone(),
        }
    }
}

/// Tower service produced by [`RequireRoleLayer`].
pub struct RequireRoleService<S> {
    inner: S,
    roles: Arc<Vec<String>>,
}

impl<S: Clone> Clone for RequireRoleService<S> {
    fn clone(&self) -> Self {
        Self {
            inner: self.inner.clone(),
            roles: self.roles.clone(),
        }
    }
}

impl<S> Service<Request<Body>> for RequireRoleService<S>
where
    S: Service<Request<Body>, Response = http::Response<Body>> + Clone + Send + 'static,
    S::Future: Send + 'static,
    S::Error: Into<Box<dyn std::error::Error + Send + Sync>> + Send + 'static,
{
    type Response = http::Response<Body>;
    type Error = S::Error;
    type Future = Pin<Box<dyn Future<Output = Result<Self::Response, Self::Error>> + Send>>;

    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        self.inner.poll_ready(cx)
    }

    fn call(&mut self, request: Request<Body>) -> Self::Future {
        let roles = self.roles.clone();
        let mut inner = self.inner.clone();
        std::mem::swap(&mut self.inner, &mut inner);

        Box::pin(async move {
            let role = match request.extensions().get::<Role>() {
                Some(r) => r,
                None => {
                    return Ok(Error::unauthorized("authentication required").into_response());
                }
            };

            if !roles.iter().any(|allowed| allowed == role.as_str()) {
                return Ok(Error::forbidden("insufficient role").into_response());
            }

            inner.call(request).await
        })
    }
}

// --- require_authenticated ---

/// Creates a guard layer that rejects requests unless a [`Role`] is present
/// in extensions. Returns 401 Unauthorized if no role is present.
///
/// Apply with `.route_layer()` so the guard runs after route matching.
pub fn require_authenticated() -> RequireAuthenticatedLayer {
    RequireAuthenticatedLayer
}

/// Tower layer produced by [`require_authenticated()`].
pub struct RequireAuthenticatedLayer;

impl Clone for RequireAuthenticatedLayer {
    fn clone(&self) -> Self {
        Self
    }
}

impl<S> Layer<S> for RequireAuthenticatedLayer {
    type Service = RequireAuthenticatedService<S>;

    fn layer(&self, inner: S) -> Self::Service {
        RequireAuthenticatedService { inner }
    }
}

/// Tower service produced by [`RequireAuthenticatedLayer`].
pub struct RequireAuthenticatedService<S> {
    inner: S,
}

impl<S: Clone> Clone for RequireAuthenticatedService<S> {
    fn clone(&self) -> Self {
        Self {
            inner: self.inner.clone(),
        }
    }
}

impl<S> Service<Request<Body>> for RequireAuthenticatedService<S>
where
    S: Service<Request<Body>, Response = http::Response<Body>> + Clone + Send + 'static,
    S::Future: Send + 'static,
    S::Error: Into<Box<dyn std::error::Error + Send + Sync>> + Send + 'static,
{
    type Response = http::Response<Body>;
    type Error = S::Error;
    type Future = Pin<Box<dyn Future<Output = Result<Self::Response, Self::Error>> + Send>>;

    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        self.inner.poll_ready(cx)
    }

    fn call(&mut self, request: Request<Body>) -> Self::Future {
        let mut inner = self.inner.clone();
        std::mem::swap(&mut self.inner, &mut inner);

        Box::pin(async move {
            if request.extensions().get::<Role>().is_none() {
                return Ok(Error::unauthorized("authentication required").into_response());
            }

            inner.call(request).await
        })
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use http::{Response, StatusCode};
    use std::convert::Infallible;
    use tower::ServiceExt;

    async fn ok_handler(_req: Request<Body>) -> Result<Response<Body>, Infallible> {
        Ok(Response::new(Body::from("ok")))
    }

    // --- require_role tests ---

    #[tokio::test]
    async fn require_role_passes_when_role_in_list() {
        let layer = require_role(["admin", "owner"]);
        let svc = layer.layer(tower::service_fn(ok_handler));

        let mut req = Request::builder().body(Body::empty()).unwrap();
        req.extensions_mut().insert(Role("admin".into()));
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::OK);
    }

    #[tokio::test]
    async fn require_role_403_when_role_not_in_list() {
        let layer = require_role(["admin", "owner"]);
        let svc = layer.layer(tower::service_fn(ok_handler));

        let mut req = Request::builder().body(Body::empty()).unwrap();
        req.extensions_mut().insert(Role("viewer".into()));
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::FORBIDDEN);
    }

    #[tokio::test]
    async fn require_role_401_when_role_missing() {
        let layer = require_role(["admin"]);
        let svc = layer.layer(tower::service_fn(ok_handler));

        let req = Request::builder().body(Body::empty()).unwrap();
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
    }

    #[tokio::test]
    async fn require_role_403_when_empty_roles_list() {
        let layer = require_role(std::iter::empty::<String>());
        let svc = layer.layer(tower::service_fn(ok_handler));

        let mut req = Request::builder().body(Body::empty()).unwrap();
        req.extensions_mut().insert(Role("admin".into()));
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::FORBIDDEN);
    }

    #[tokio::test]
    async fn require_role_empty_string_matches() {
        let layer = require_role([""]);
        let svc = layer.layer(tower::service_fn(ok_handler));

        let mut req = Request::builder().body(Body::empty()).unwrap();
        req.extensions_mut().insert(Role("".into()));
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::OK);
    }

    #[tokio::test]
    async fn require_role_does_not_call_inner_on_reject() {
        use std::sync::atomic::{AtomicBool, Ordering};

        let called = Arc::new(AtomicBool::new(false));
        let called_clone = called.clone();

        let layer = require_role(["admin"]);
        let svc = layer.layer(tower::service_fn(move |_req: Request<Body>| {
            let called = called_clone.clone();
            async move {
                called.store(true, Ordering::SeqCst);
                Ok::<_, Infallible>(Response::new(Body::from("should not reach")))
            }
        }));

        let mut req = Request::builder().body(Body::empty()).unwrap();
        req.extensions_mut().insert(Role("viewer".into()));
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::FORBIDDEN);
        assert!(!called.load(Ordering::SeqCst));
    }

    // --- require_authenticated tests ---

    #[tokio::test]
    async fn require_authenticated_passes_when_role_present() {
        let layer = require_authenticated();
        let svc = layer.layer(tower::service_fn(ok_handler));

        let mut req = Request::builder().body(Body::empty()).unwrap();
        req.extensions_mut().insert(Role("viewer".into()));
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::OK);
    }

    #[tokio::test]
    async fn require_authenticated_401_when_role_missing() {
        let layer = require_authenticated();
        let svc = layer.layer(tower::service_fn(ok_handler));

        let req = Request::builder().body(Body::empty()).unwrap();
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
    }

    #[tokio::test]
    async fn require_authenticated_does_not_call_inner_on_reject() {
        use std::sync::atomic::{AtomicBool, Ordering};

        let called = Arc::new(AtomicBool::new(false));
        let called_clone = called.clone();

        let layer = require_authenticated();
        let svc = layer.layer(tower::service_fn(move |_req: Request<Body>| {
            let called = called_clone.clone();
            async move {
                called.store(true, Ordering::SeqCst);
                Ok::<_, Infallible>(Response::new(Body::from("should not reach")))
            }
        }));

        let req = Request::builder().body(Body::empty()).unwrap();
        let resp = svc.oneshot(req).await.unwrap();
        assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
        assert!(!called.load(Ordering::SeqCst));
    }
}