ullun/
middleware.rs

1//! Middleware types and traits
2
3use crate::error::{Error, Result};
4use crate::request::Request;
5use crate::response::Response;
6use async_trait::async_trait;
7use std::sync::Arc;
8
9/// Middleware trait
10#[async_trait]
11pub trait Middleware: Send + Sync + 'static {
12    async fn handle(&self, req: Request, next: Next) -> Result<Response>;
13}
14
15/// Next middleware in chain
16#[derive(Clone)]
17pub struct Next {
18    middlewares: Arc<Vec<Arc<dyn Middleware>>>,
19    index: usize,
20}
21
22impl Next {
23    pub fn new(middlewares: Arc<Vec<Arc<dyn Middleware>>>) -> Self {
24        Self {
25            middlewares,
26            index: 0,
27        }
28    }
29
30    pub async fn run(mut self, req: Request) -> Result<Response> {
31        if self.index < self.middlewares.len() {
32            let middleware = self.middlewares[self.index].clone();
33            self.index += 1;
34            middleware.handle(req, self).await
35        } else {
36            // End of chain without handler match
37            Err(Error::not_found("Route not found"))
38        }
39    }
40}
41
42/// A handler wrapped in its own middleware stack (used by route groups)
43pub(crate) struct Layered {
44    middlewares: Vec<Arc<dyn Middleware>>,
45    inner: crate::handler::DynHandler,
46}
47
48impl Layered {
49    pub(crate) fn new(
50        middlewares: Vec<Arc<dyn Middleware>>,
51        inner: crate::handler::DynHandler,
52    ) -> Self {
53        Self { middlewares, inner }
54    }
55}
56
57#[async_trait]
58impl crate::handler::Handler for Layered {
59    async fn call(&self, req: Request) -> Result<Response> {
60        let inner = self.inner.clone();
61        let mut chain = self.middlewares.clone();
62        chain.push(Arc::new(move |req: Request, _next: Next| {
63            let inner = inner.clone();
64            async move { inner.call(req).await }
65        }));
66        Next::new(Arc::new(chain)).run(req).await
67    }
68}
69
70/// Implement Middleware for async functions
71#[async_trait]
72impl<F, Fut> Middleware for F
73where
74    F: Fn(Request, Next) -> Fut + Send + Sync + 'static,
75    Fut: std::future::Future<Output = Result<Response>> + Send + 'static,
76{
77    async fn handle(&self, req: Request, next: Next) -> Result<Response> {
78        (self)(req, next).await
79    }
80}
81
82/// Logger middleware
83pub async fn logger(req: Request, next: Next) -> Result<Response> {
84    let method = req.method.clone();
85    let uri = req.uri.clone();
86    let start = std::time::Instant::now();
87
88    let response = next.run(req).await;
89
90    let duration = start.elapsed();
91    println!("{} {} - {:?}", method, uri, duration);
92
93    response
94}
95
96/// CORS middleware with preflight support
97pub fn cors(
98    allowed_origins: Vec<String>,
99) -> impl Fn(
100    Request,
101    Next,
102) -> std::pin::Pin<Box<dyn std::future::Future<Output = Result<Response>> + Send>>
103       + Clone {
104    move |req: Request, next: Next| {
105        let origins = allowed_origins.clone();
106        Box::pin(async move {
107            // Handle preflight OPTIONS requests
108            if req.method == http::Method::OPTIONS {
109                let mut response = Response::new(http::StatusCode::NO_CONTENT);
110
111                if !origins.is_empty() {
112                    let origin = if origins.contains(&"*".to_string()) {
113                        "*".to_string()
114                    } else {
115                        // In production, should check Origin header against allowed list
116                        origins[0].clone()
117                    };
118                    response = response.with_header("Access-Control-Allow-Origin", origin);
119                    response = response.with_header(
120                        "Access-Control-Allow-Methods",
121                        "GET, POST, PUT, DELETE, PATCH, OPTIONS",
122                    );
123                    response = response.with_header(
124                        "Access-Control-Allow-Headers",
125                        "Content-Type, Authorization",
126                    );
127                    response = response.with_header("Access-Control-Max-Age", "86400");
128                }
129
130                return Ok(response);
131            }
132
133            // Regular request - add CORS headers to response
134            let mut response = next.run(req).await?;
135
136            if !origins.is_empty() {
137                let origin = if origins.contains(&"*".to_string()) {
138                    "*".to_string()
139                } else {
140                    origins[0].clone()
141                };
142                response = response.with_header("Access-Control-Allow-Origin", origin);
143                response = response.with_header("Access-Control-Allow-Credentials", "true");
144            }
145
146            Ok(response)
147        })
148    }
149}
ullun/middleware.rs

ullun/
middleware.rs
