How to implement a `rocket::request::FromRequest` to a tuple struct? - rust

Question

TLDR;
Is it possible to implement rocket::request::FromRequest in a tuple struct? (Or is it called newtype idiom?)
#[cfg(target_os = "windows")]
pub struct IpAddWrapper(std::net::SocketAddr);
#[cfg(any(not(target_os = "windows"), feature = "integration_test"))]
pub struct IpAddWrapper(IpAddr);
pub struct IpAddr<'r>(&'r str);
#[rocket::async_trait]
impl<'r> FromRequest<'r> for IpAddr<'r> {
type Error = &'r str;
async fn from_request(request: &'r Request<'_>) -> Outcome<Self, Self::Error> {
let keys: Vec<_> = request.headers().get("X-Real-IP").collect();
match keys.len() {
0 => Outcome::Failure((Status::NotFound, "IP Address not found")),
1 => Outcome::Success(IpAddr(keys[0])),
_ => Outcome::Failure((Status::NotFound, "Indeterminable Error")),
}
}
}
In my Cargo.toml
...
[dependencies]
rocket = { version = "0.5.0-rc.1", features = ["json"]}
...
Context, if you're interested
I have 3 types of compilation of a middleware for testing
(1) In Ubuntu and/or running integration tests
(2) Windows, whilst running the GUI app in Java
(3) Windows, to run integration tests
My goal is to get the IP Address of the HTTP request from the client app or the GUI app
For some reason (which means I don't exactly know the reason), if I use as a function parameter/argument the std::net::SocketAddr type, running (2), I easily get the IP Address on a request, even if there's no header explicitly inserted in the GUI app's request (I think gson-2.6.2.jar took care of that).
But running (1) (in correspondence with nginx) and (3) (using use rocket::local::blocking::Client), using the same function with a parameter/argument of std::net::SocketAddr, I encounter problems.
The solution I used for now is to make the IP Address explicit in the client's side with
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
// in GET
con.setRequestMethod("GET");
// IN POST
// con.setRequestMethod("POST");
con.setRequestProperty("api-key", http.APISECRET);
con.setRequestProperty("ContentType", "application/json");
con.setRequestProperty("X-Real-IP", "0.0.0.0");
But I'm curious if the question I asked above is possible and I'm just experiencing technical issues due to inexperience.
Thanks for reading.
INDIRECT ANSWER
The solution I have for now, which doesn't answer my question, but it's something that I think is "clean". Thanks to #cameron1024's comment, I did some searching and found this, and used snippets of codes over there and now I have a new code structure, not needing conditional compilation anymore
#[post("/index?<c>&<a>", rank = 1)]
fn some_post(
_key: ApiKey,
remote_addr: IpAddr,
c: String,
a: String,
) -> Result<(), ErrorResponse> { ... }
pub struct IpAddr(String);
#[rocket::async_trait]
impl<'r> FromRequest<'r> for IpAddr {
type Error = &'r str;
async fn from_request(request: &'r Request<'_>) -> Outcome<Self, Self::Error> {
match request.remote() {
Some(addr) => Outcome::Success(IpAddr(addr.to_string())),
None => {
let keys: Vec<_> = request.headers().get("X-Real-IP").collect();
match keys.len() {
0 => Outcome::Failure((Status::NotFound, "IP Address not found")),
1 => Outcome::Success(IpAddr(keys[0].to_string())),
_ => Outcome::Failure((Status::NotFound, "Indeterminable Error")),
}
}
}
}
}
And also on the Java GUI & HTTP client app, I don't have to use the code above
con.setRequestProperty("X-Real-IP", "0.0.0.0");
That I have to comment out when compiling it for deployment.
Woohoo!
MY ACCEPTED SOLUTION
but still not answering the post question
My problem with the indirect answer (above) is that there will always be one unnecessary step in determining the IP address, either prioritizing checking of the header "X-Real-IP" first or the std::net::SocketAddr. And also it might be another opportunity for attackers since there’s two allowable header keys for IP addresses, and in deployment, only a single header key is accepted: "X-Real-IP".
So I sought for other solutions and thought about type aliasing and used this SO answer: How to make type aliases based on compile flags in Rust?
The following is my current code:
// guards.rs
#[cfg(all(target_os = "windows", not(feature = "integration_test")))]
pub type IpAddrAlias = std::net::SocketAddr;
#[cfg(any(not(target_os = "windows"), feature = "integration_test"))]
pub type IpAddrAlias<'r> = IpAddr<'r>;
pub struct IpAddr<'r>(&'r str);
#[rocket::async_trait]
impl<'r> FromRequest<'r> for IpAddr<'r> {
type Error = &'r str;
async fn from_request(request: &'r Request<'_>) -> Outcome<Self, Self::Error> {
let keys: Vec<_> = request.headers().get("X-Real-IP").collect();
match keys.len() {
0 => Outcome::Failure((Status::NotFound, "IP Address not found")),
1 => Outcome::Success(IpAddr(keys[0])),
_ => Outcome::Failure((Status::NotFound, "Indeterminable Error")),
}
}
}
// main.rs
mod utils;
use utils::guards::{ApiKey, UserAgent, IpAddrAlias};
#[post("/index?<c>&<a>", rank = 1)]
fn some_post(
_key: ApiKey,
remote_addr: IpAddrAlias,
c: String,
a: String,
) -> Result<Redirect, ErrorResponse> { ... }
Still woohoo for Rust!