feat(files): add possibility to redirect to slash-ended path (#1134)

When accessing to a folder without a final slash, the index file will be loaded ok, but if it has
references (like a css or an image in an html file) these resources won't be loaded correctly if
they are using relative paths. In order to solve this, this PR adds the possibility to detect
folders without a final slash and make a 302 redirect to mitigate this issue. The behavior is off by
default. We're adding a new method called `redirect_to_slash_directory` which can be used to enable
this behavior.

actix-files/CHANGES.md

@@ -1,5 +1,9 @@
 # Changes
 
+## [0.1.6] - TBD
+
+* Add option to redirect to a slash-ended path `Files` #1132
+
 ## [0.1.5] - 2019-10-08
 
 * Bump up `mime_guess` crate version to 2.0.1
@@ -8,17 +12,14 @@
 
 * Allow user defined request guards for `Files` #1113
   
-
 ## [0.1.4] - 2019-07-20
 
 * Allow to disable `Content-Disposition` header #686
 
-
 ## [0.1.3] - 2019-06-28
 
 * Do not set `Content-Length` header, let actix-http set it #930
 
-
 ## [0.1.2] - 2019-06-13
 
 * Content-Length is 0 for NamedFile HEAD request #914

actix-files/src/lib.rs

@@ -233,6 +233,7 @@ pub struct Files {
     directory: PathBuf,
     index: Option<String>,
     show_index: bool,
+    redirect_to_slash: bool,
     default: Rc<RefCell<Option<Rc<HttpNewService>>>>,
     renderer: Rc<DirectoryRenderer>,
     mime_override: Option<Rc<MimeOverride>>,
@@ -246,6 +247,7 @@ impl Clone for Files {
             directory: self.directory.clone(),
             index: self.index.clone(),
             show_index: self.show_index,
+            redirect_to_slash: self.redirect_to_slash,
             default: self.default.clone(),
             renderer: self.renderer.clone(),
             file_flags: self.file_flags,
@@ -273,6 +275,7 @@ impl Files {
             directory: dir,
             index: None,
             show_index: false,
+            redirect_to_slash: false,
             default: Rc::new(RefCell::new(None)),
             renderer: Rc::new(directory_listing),
             mime_override: None,
@@ -289,6 +292,14 @@ impl Files {
         self
     }
 
+    /// Redirects to a slash-ended path when browsing a directory.
+    ///
+    /// By default never redirect.
+    pub fn redirect_to_slash_directory(mut self) -> Self {
+        self.redirect_to_slash = true;
+        self
+    }
+
     /// Set custom directory renderer
     pub fn files_listing_renderer<F>(mut self, f: F) -> Self
     where
@@ -389,10 +400,10 @@ impl HttpServiceFactory for Files {
 }
 
 impl NewService for Files {
-    type Config = ();
     type Request = ServiceRequest;
     type Response = ServiceResponse;
     type Error = Error;
+    type Config = ();
     type Service = FilesService;
     type InitError = ();
     type Future = Box<dyn Future<Item = Self::Service, Error = Self::InitError>>;
@@ -402,6 +413,7 @@ impl NewService for Files {
             directory: self.directory.clone(),
             index: self.index.clone(),
             show_index: self.show_index,
+            redirect_to_slash: self.redirect_to_slash,
             default: None,
             renderer: self.renderer.clone(),
             mime_override: self.mime_override.clone(),
@@ -429,6 +441,7 @@ pub struct FilesService {
     directory: PathBuf,
     index: Option<String>,
     show_index: bool,
+    redirect_to_slash: bool,
     default: Option<HttpService>,
     renderer: Rc<DirectoryRenderer>,
     mime_override: Option<Rc<MimeOverride>>,
@@ -502,6 +515,16 @@ impl Service for FilesService {
 
         if path.is_dir() {
             if let Some(ref redir_index) = self.index {
+                if self.redirect_to_slash && !req.path().ends_with('/') {
+                    let redirect_to = format!("{}/", req.path());
+                    return Either::A(ok(req.into_response(
+                        HttpResponse::Found()
+                            .header(header::LOCATION, redirect_to)
+                            .body("")
+                            .into_body(),
+                    )));
+                }
+
                 let path = path.join(redir_index);
 
                 match NamedFile::open(path) {
@@ -1169,6 +1192,34 @@ mod tests {
         assert!(format!("{:?}", bytes).contains("/tests/test.png"));
     }
 
+    #[test]
+    fn test_redirect_to_slash_directory() {
+        // should not redirect if no index
+        let mut srv = test::init_service(
+            App::new().service(Files::new("/", ".").redirect_to_slash_directory()),
+        );
+        let req = TestRequest::with_uri("/tests").to_request();
+        let resp = test::call_service(&mut srv, req);
+        assert_eq!(resp.status(), StatusCode::NOT_FOUND);
+
+        // should redirect if index present
+        let mut srv = test::init_service(
+            App::new().service(
+                Files::new("/", ".")
+                    .index_file("test.png")
+                    .redirect_to_slash_directory(),
+            ),
+        );
+        let req = TestRequest::with_uri("/tests").to_request();
+        let resp = test::call_service(&mut srv, req);
+        assert_eq!(resp.status(), StatusCode::FOUND);
+
+        // should not redirect if the path is wrong
+        let req = TestRequest::with_uri("/not_existing").to_request();
+        let resp = test::call_service(&mut srv, req);
+        assert_eq!(resp.status(), StatusCode::NOT_FOUND);
+    }
+
     #[test]
     fn test_static_files_bad_directory() {
         let _st: Files = Files::new("/", "missing");