Expose the remote address via `remote()` in `Request`.

This commit also includes the following changes:

  * `FromRequest` for `SocketAddr` implemented: extracts remote address.
  * All built-in `FromRequest` implementations are documented.
  * Request preprocessing overrides remote IP with value from X-Real-IP header.
  * `MockRequest` allows setting the remote address with `remote()`.

Resolves #38.

lib/src/request/from_request.rs

@@ -1,4 +1,5 @@
 use std::fmt::Debug;
+use std::net::SocketAddr;
 
 use outcome::{self, IntoOutcome};
 use request::Request;
@@ -65,6 +66,65 @@ impl<S, E> IntoOutcome<S, (Status, E), ()> for Result<S, E> {
 ///   matching request. Note that users can request an `Option<S>` to catch
 ///   `Forward`s.
 ///
+/// # Provided Implementations
+///
+/// Rocket implements `FromRequest` for several built-in types. Their behavior
+/// is documented here.
+///
+///   * **URI**
+///
+///     Extracts the [URI](/rocket/http/uri/struct.URI.html) from the incoming
+///     request.
+///
+///     _This implementation always returns successfully._
+///
+///   * **Method**
+///
+///     Extracts the [Method](/rocket/http/enum.Method.html) from the incoming
+///     request.
+///
+///     _This implementation always returns successfully._
+///
+///   * **&Cookies**
+///
+///     Returns a borrow to the [Cookies](/rocket/http/type.Cookies.html) in the
+///     incoming request. Note that `Cookies` implements internal mutability, so
+///     a handle to `&Cookies` allows you to get _and_ set cookies in the
+///     request.
+///
+///     _This implementation always returns successfully._
+///
+///   * **ContentType**
+///
+///     Extracts the [ContentType](/rocket/http/struct.ContentType.html) from
+///     the incoming request. If the request didn't specify a Content-Type, a
+///     Content-Type of `*/*` (`Any`) is returned.
+///
+///     _This implementation always returns successfully._
+///
+///   * **SocketAddr**
+///
+///     Extracts the remote address of the incoming request as a `SocketAddr`.
+///     If the remote address is not known, the request is forwarded.
+///
+///     _This implementation always returns successfully._
+///
+///   * **Option&lt;T>** _where_ **T: FromRequest**
+///
+///     The type `T` is derived from the incoming request using `T`'s
+///     `FromRequest` implementation. If the derivation is a `Success`, the
+///     dervived value is returned in `Some`. Otherwise, a `None` is returned.
+///
+///     _This implementation always returns successfully._
+///
+///   * **Result&lt;T, T::Error>** _where_ **T: FromRequest**
+///
+///     The type `T` is derived from the incoming request using `T`'s
+///     `FromRequest` implementation. If derivation is a `Success`, the value is
+///     returned in `Ok`. If the derivation is a `Failure`, the error value is
+///     returned in `Err`. If the derivation is a `Forward`, the request is
+///     forwarded.
+///
 /// # Example
 ///
 /// Imagine you're running an authenticated API service that requires that some
@@ -161,6 +221,17 @@ impl<'a, 'r> FromRequest<'a, 'r> for ContentType {
     }
 }
 
+impl<'a, 'r> FromRequest<'a, 'r> for SocketAddr {
+    type Error = ();
+
+    fn from_request(request: &'a Request<'r>) -> Outcome<Self, Self::Error> {
+        match request.remote() {
+            Some(addr) => Success(addr),
+            None => Forward(())
+        }
+    }
+}
+
 impl<'a, 'r, T: FromRequest<'a, 'r>> FromRequest<'a, 'r> for Result<T, T::Error> {
     type Error = ();
 

lib/src/request/request.rs

@@ -1,4 +1,5 @@
 use std::cell::RefCell;
+use std::net::SocketAddr;
 use std::fmt;
 
 use term_painter::Color::*;
@@ -24,6 +25,7 @@ pub struct Request<'r> {
     method: Method,
     uri: URI<'r>,
     headers: HeaderMap<'r>,
+    remote: Option<SocketAddr>,
     params: RefCell<Vec<(usize, usize)>>,
     cookies: Cookies,
 }
@@ -46,6 +48,7 @@ impl<'r> Request<'r> {
             method: method,
             uri: uri.into(),
             headers: HeaderMap::new(),
+            remote: None,
             params: RefCell::new(Vec::new()),
             cookies: Cookies::new(&[]),
         }
@@ -123,6 +126,49 @@ impl<'r> Request<'r> {
         self.params = RefCell::new(Vec::new());
     }
 
+    /// Returns the address of the remote connection that initiated this
+    /// request if the address is known. If the address is not known, `None` is
+    /// returned.
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// use rocket::Request;
+    /// use rocket::http::Method;
+    ///
+    /// let request = Request::new(Method::Get, "/uri");
+    /// assert!(request.remote().is_none());
+    /// ```
+    #[inline(always)]
+    pub fn remote(&self) -> Option<SocketAddr> {
+        self.remote
+    }
+
+    /// Sets the remote address of `self` to `address`.
+    ///
+    /// # Example
+    ///
+    /// Set the remote address to be 127.0.0.1:8000:
+    ///
+    /// ```rust
+    /// use rocket::Request;
+    /// use rocket::http::Method;
+    /// use std::net::{SocketAddr, IpAddr, Ipv4Addr};
+    ///
+    /// let mut request = Request::new(Method::Get, "/uri");
+    ///
+    /// let (ip, port) = (IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8000);
+    /// let localhost = SocketAddr::new(ip, port);
+    /// request.set_remote(localhost);
+    ///
+    /// assert_eq!(request.remote(), Some(localhost));
+    /// ```
+    #[doc(hidden)]
+    #[inline(always)]
+    pub fn set_remote(&mut self, address: SocketAddr) {
+        self.remote = Some(address);
+    }
+
     /// Returns a `HeaderMap` of all of the headers in `self`.
     ///
     /// # Example
@@ -185,8 +231,8 @@ impl<'r> Request<'r> {
 
     /// Returns a borrow to the cookies in `self`.
     ///
-    /// Note that `Cookie` implements internal mutability, so this method allows
+    /// Note that `Cookies` implements internal mutability, so this method
-    /// you to get _and_ set cookies in `self`.
+    /// allows you to get _and_ set cookies in `self`.
     ///
     /// # Example
     ///
@@ -274,6 +320,7 @@ impl<'r> Request<'r> {
     /// Set `self`'s parameters given that the route used to reach this request
     /// was `route`. This should only be used internally by `Rocket` as improper
     /// use may result in out of bounds indexing.
+    /// TODO: Figure out the mount path from here.
     #[doc(hidden)]
     #[inline(always)]
     pub fn set_params(&self, route: &Route) {
@@ -348,8 +395,9 @@ impl<'r> Request<'r> {
     #[doc(hidden)]
     pub fn from_hyp(h_method: hyper::Method,
                     h_headers: hyper::header::Headers,
-                    h_uri: hyper::RequestUri)
+                    h_uri: hyper::RequestUri,
-                    -> Result<Request<'static>, String> {
+                    h_addr: SocketAddr,
+                    ) -> Result<Request<'static>, String> {
         // Get a copy of the URI for later use.
         let uri = match h_uri {
             hyper::RequestUri::AbsolutePath(s) => s,
@@ -376,6 +424,9 @@ impl<'r> Request<'r> {
             request.add_header(header);
         }
 
+        // Set the remote address.
+        request.set_remote(h_addr);
+
         Ok(request)
     }
 }

lib/src/rocket.rs

@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 use std::str::from_utf8_unchecked;
 use std::cmp::min;
+use std::net::SocketAddr;
 use std::io::{self, Write};
 
 use term_painter::Color::*;
@@ -41,11 +42,11 @@ impl hyper::Handler for Rocket {
                       hyp_req: hyper::Request<'h, 'k>,
                       res: hyper::FreshResponse<'h>) {
         // Get all of the information from Hyper.
-        let (_, h_method, h_headers, h_uri, _, h_body) = hyp_req.deconstruct();
+        let (h_addr, h_method, h_headers, h_uri, _, h_body) = hyp_req.deconstruct();
 
         // Convert the Hyper request into a Rocket request.
-        let mut request = match Request::from_hyp(h_method, h_headers, h_uri) {
+        let mut req = match Request::from_hyp(h_method, h_headers, h_uri, h_addr) {
-            Ok(request) => request,
+            Ok(req) => req,
             Err(e) => {
                 error!("Bad incoming request: {}", e);
                 let dummy = Request::new(Method::Get, URI::new("<unknown>"));
@@ -59,13 +60,13 @@ impl hyper::Handler for Rocket {
             Ok(data) => data,
             Err(reason) => {
                 error_!("Bad data in request: {}", reason);
-                let r = self.handle_error(Status::InternalServerError, &request);
+                let r = self.handle_error(Status::InternalServerError, &req);
                 return self.issue_response(r, res);
             }
         };
 
         // Dispatch the request to get a response, then write that response out.
-        let response = self.dispatch(&mut request, data);
+        let response = self.dispatch(&mut req, data);
         self.issue_response(response, res)
     }
 }
@@ -132,15 +133,33 @@ impl Rocket {
         }
     }
 
-    /// Preprocess the request for Rocket-specific things. At this time, we're
+    /// Preprocess the request for Rocket things. Currently, this means:
-    /// only checking for _method in forms. Keep this in-sync with derive_form
+    ///
-    /// when preprocessing form fields.
+    ///   * Rewriting the method in the request if _method form field exists.
+    ///   * Rewriting the remote IP if the 'X-Real-IP' header is set.
+    ///
+    /// Keep this in-sync with derive_form when preprocessing form fields.
     fn preprocess_request(&self, req: &mut Request, data: &Data) {
+        // Rewrite the remote IP address. The request must already have an
+        // address associated with it to do this since we need to know the port.
+        if let Some(current) = req.remote() {
+            let ip = req.headers()
+                .get_one("X-Real-IP")
+                .and_then(|ip_str| ip_str.parse().map_err(|_| {
+                    warn_!("The 'X-Real-IP' header is malformed: {}", ip_str)
+                }).ok());
+
+            if let Some(ip) = ip {
+                req.set_remote(SocketAddr::new(ip, current.port()));
+            }
+        }
+
         // Check if this is a form and if the form contains the special _method
         // field which we use to reinterpret the request's method.
         let data_len = data.peek().len();
         let (min_len, max_len) = ("_method=get".len(), "_method=delete".len());
-        if req.method() == Method::Post && req.content_type().is_form() && data_len >= min_len {
+        let is_form = req.content_type().is_form();
+        if is_form && req.method() == Method::Post && data_len >= min_len {
             let form = unsafe {
                 from_utf8_unchecked(&data.peek()[..min(data_len, max_len)])
             };
@@ -157,6 +176,8 @@ impl Rocket {
     #[doc(hidden)]
     #[inline(always)]
     pub fn dispatch<'r>(&self, request: &'r mut Request, data: Data) -> Response<'r> {
+        info!("{}:", request);
+
         // Do a bit of preprocessing before routing.
         self.preprocess_request(request, &data);
 
@@ -207,7 +228,6 @@ impl Rocket {
     pub fn route<'r>(&self, request: &'r Request, mut data: Data)
             -> handler::Outcome<'r> {
         // Go through the list of matching routes until we fail or succeed.
-        info!("{}:", request);
         let matches = self.router.route(request);
         for route in matches {
             // Retrieve and set the requests parameters.

lib/src/testing.rs

@@ -108,6 +108,8 @@
 use ::{Rocket, Request, Response, Data};
 use http::{Method, Header, Cookie};
 
+use std::net::SocketAddr;
+
 /// A type for mocking requests for testing Rocket applications.
 pub struct MockRequest {
     request: Request<'static>,
@@ -143,6 +145,44 @@ impl MockRequest {
         self
     }
 
+    /// Set the remote address of this request.
+    ///
+    /// # Examples
+    ///
+    /// Set the remote address to "8.8.8.8:80":
+    ///
+    /// ```rust
+    /// use rocket::http::Method::*;
+    /// use rocket::testing::MockRequest;
+    ///
+    /// let address = "8.8.8.8:80".parse().unwrap();
+    /// let req = MockRequest::new(Get, "/").remote(address);
+    /// ```
+    #[inline]
+    pub fn remote(mut self, address: SocketAddr) -> Self {
+        self.request.set_remote(address);
+        self
+    }
+
+    /// Adds a header to this request. Does not consume `self`.
+    ///
+    /// # Examples
+    ///
+    /// Add the Content-Type header:
+    ///
+    /// ```rust
+    /// use rocket::http::Method::*;
+    /// use rocket::testing::MockRequest;
+    /// use rocket::http::ContentType;
+    ///
+    /// let mut req = MockRequest::new(Get, "/");
+    /// req.add_header(ContentType::JSON);
+    /// ```
+    #[inline]
+    pub fn add_header<'h, H: Into<Header<'static>>>(&mut self, header: H) {
+        self.request.add_header(header.into());
+    }
+
     /// Add a cookie to this request.
     ///
     /// # Examples

lib/tests/remote-rewrite.rs

@@ -0,0 +1,87 @@
+#![feature(plugin, custom_derive)]
+#![plugin(rocket_codegen)]
+
+extern crate rocket;
+
+use std::net::SocketAddr;
+
+#[get("/")]
+fn get_ip(remote: SocketAddr) -> String {
+    remote.to_string()
+}
+
+#[cfg(feature = "testing")]
+mod remote_rewrite_tests {
+    use super::*;
+    use rocket::testing::MockRequest;
+    use rocket::http::Method::*;
+    use rocket::http::{Header, Status};
+
+    use std::net::SocketAddr;
+
+    const KNOWN_IP: &'static str = "127.0.0.1:8000";
+
+    fn check_ip(header: Option<Header<'static>>, ip: Option<String>) {
+        let address: SocketAddr = KNOWN_IP.parse().unwrap();
+        let port = address.port();
+
+        let rocket = rocket::ignite().mount("/", routes![get_ip]);
+        let mut req = MockRequest::new(Get, "/").remote(address);
+        if let Some(header) = header {
+            req.add_header(header);
+        }
+
+        let mut response = req.dispatch_with(&rocket);
+        assert_eq!(response.status(), Status::Ok);
+        let body_str = response.body().and_then(|b| b.into_string());
+        match ip {
+            Some(ip) => assert_eq!(body_str, Some(format!("{}:{}", ip, port))),
+            None => assert_eq!(body_str, Some(KNOWN_IP.into()))
+        }
+    }
+
+    #[test]
+    fn x_real_ip_rewrites() {
+        let ip = "8.8.8.8";
+        check_ip(Some(Header::new("X-Real-IP", ip)), Some(ip.to_string()));
+
+        let ip = "129.120.111.200";
+        check_ip(Some(Header::new("X-Real-IP", ip)), Some(ip.to_string()));
+    }
+
+    #[test]
+    fn x_real_ip_rewrites_ipv6() {
+        let ip = "2001:db8:0:1:1:1:1:1";
+        check_ip(Some(Header::new("X-Real-IP", ip)), Some(format!("[{}]", ip)));
+
+        let ip = "2001:db8::2:1";
+        check_ip(Some(Header::new("X-Real-IP", ip)), Some(format!("[{}]", ip)));
+    }
+
+    #[test]
+    fn uncased_header_rewrites() {
+        let ip = "8.8.8.8";
+        check_ip(Some(Header::new("x-REAL-ip", ip)), Some(ip.to_string()));
+
+        let ip = "1.2.3.4";
+        check_ip(Some(Header::new("x-real-ip", ip)), Some(ip.to_string()));
+    }
+
+    #[test]
+    fn no_header_no_rewrite() {
+        check_ip(Some(Header::new("real-ip", "?")), None);
+        check_ip(None, None);
+    }
+
+    #[test]
+    fn bad_header_doesnt_rewrite() {
+        let ip = "092348092348";
+        check_ip(Some(Header::new("X-Real-IP", ip)), None);
+
+        let ip = "1200:100000:0120129";
+        check_ip(Some(Header::new("X-Real-IP", ip)), None);
+
+        let ip = "192.168.1.900";
+        check_ip(Some(Header::new("X-Real-IP", ip)), None);
+    }
+}