From 1e7f97a111c7fb0b047253bd4b0882d2fd471fb8 Mon Sep 17 00:00:00 2001
From: Douman <douman@gmx.se>
Date: Fri, 19 Apr 2019 23:53:49 +0300
Subject: [PATCH] Add Normalization middleware for in place (#783)

---
 src/middleware/mod.rs       |   1 +
 src/middleware/normalize.rs | 109 ++++++++++++++++++++++++++++++++++++
 2 files changed, 110 insertions(+)
 create mode 100644 src/middleware/normalize.rs

diff --git a/src/middleware/mod.rs b/src/middleware/mod.rs
index 59d467c0..3df92625 100644
--- a/src/middleware/mod.rs
+++ b/src/middleware/mod.rs
@@ -6,6 +6,7 @@ pub mod cors;
 mod defaultheaders;
 pub mod errhandlers;
 mod logger;
+pub mod normalize;
 
 pub use self::defaultheaders::DefaultHeaders;
 pub use self::logger::Logger;
diff --git a/src/middleware/normalize.rs b/src/middleware/normalize.rs
new file mode 100644
index 00000000..4b0afe7a
--- /dev/null
+++ b/src/middleware/normalize.rs
@@ -0,0 +1,109 @@
+//! `Middleware` to normalize request's URI
+
+use regex::Regex;
+use actix_service::{Service, Transform};
+use futures::future::{self, FutureResult};
+
+use crate::service::{ServiceRequest, ServiceResponse};
+
+#[derive(Default, Clone, Copy)]
+/// `Middleware` to normalize request's URI in place
+///
+/// Performs following:
+///
+/// - Merges multiple slashes into one.
+pub struct NormalizePath;
+
+impl<S> Transform<S> for NormalizePath
+where
+    S: Service<Request = ServiceRequest, Response = ServiceResponse>,
+{
+    type Request = ServiceRequest;
+    type Response = ServiceResponse;
+    type Error = S::Error;
+    type InitError = ();
+    type Transform = NormalizePathNormalization<S>;
+    type Future = FutureResult<Self::Transform, Self::InitError>;
+
+    fn new_transform(&self, service: S) -> Self::Future {
+        future::ok(NormalizePathNormalization {
+            service,
+            merge_slash: Regex::new("//+").unwrap()
+        })
+    }
+}
+
+pub struct NormalizePathNormalization<S> {
+    service: S,
+    merge_slash: Regex,
+}
+
+impl<S> Service for NormalizePathNormalization<S>
+where
+    S: Service<Request = ServiceRequest, Response = ServiceResponse>,
+{
+    type Request = ServiceRequest;
+    type Response = ServiceResponse;
+    type Error = S::Error;
+    type Future = S::Future;
+
+    fn poll_ready(&mut self) -> futures::Poll<(), Self::Error> {
+        self.service.poll_ready()
+    }
+
+    fn call(&mut self, mut req: ServiceRequest) -> Self::Future {
+        let head = req.head_mut();
+
+        let path = head.uri.path();
+        let original_len = path.len();
+        let path = self.merge_slash.replace_all(path, "/");
+
+        if original_len != path.len() {
+            head.uri = path.parse().unwrap();
+        }
+
+        self.service.call(req)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use actix_service::FnService;
+
+    use super::*;
+    use crate::dev::ServiceRequest;
+    use crate::http::header::CONTENT_TYPE;
+    use crate::test::{block_on, TestRequest};
+    use crate::HttpResponse;
+
+    #[test]
+    fn test_in_place_normalization() {
+        let srv = FnService::new(|req: ServiceRequest| {
+            assert_eq!("/v1/something/", req.path());
+            req.into_response(HttpResponse::Ok().finish())
+        });
+
+        let mut normalize = block_on(NormalizePath.new_transform(srv)).unwrap();
+
+        let req = TestRequest::with_uri("/v1//something////").to_srv_request();
+        let res = block_on(normalize.call(req)).unwrap();
+        assert!(res.status().is_success());
+    }
+
+    #[test]
+    fn should_normalize_nothing() {
+        const URI: &str = "/v1/something/";
+
+        let srv = FnService::new(|req: ServiceRequest| {
+            assert_eq!(URI, req.path());
+            req.into_response(HttpResponse::Ok().finish())
+        });
+
+        let mut normalize = block_on(NormalizePath.new_transform(srv)).unwrap();
+
+        let req = TestRequest::with_uri(URI).to_srv_request();
+        let res = block_on(normalize.call(req)).unwrap();
+        assert!(res.status().is_success());
+    }
+
+}