perf: remove unnecessary allocation when writing http dates (#3261)

actix-http/CHANGES.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Changed
+
+- Minimum supported Rust version (MSRV) is now 1.70.
+
 ## 3.6.0
 
 ### Added

actix-http/Cargo.toml

@@ -126,6 +126,7 @@ actix-web = "4"
 
 async-stream = "0.3"
 criterion = { version = "0.5", features = ["html_reports"] }
+divan = "0.1.8"
 env_logger = "0.10"
 futures-util = { version = "0.3.17", default-features = false, features = ["alloc"] }
 memchr = "2.4"
@@ -153,3 +154,7 @@ required-features = ["http2", "rustls-0_22"]
 name = "response-body-compression"
 harness = false
 required-features = ["compress-brotli", "compress-gzip", "compress-zstd"]
+
+[[bench]]
+name = "date-formatting"
+harness = false

actix-http/README.md

@@ -6,7 +6,7 @@
 
 [![crates.io](https://img.shields.io/crates/v/actix-http?label=latest)](https://crates.io/crates/actix-http)
 [![Documentation](https://docs.rs/actix-http/badge.svg?version=3.6.0)](https://docs.rs/actix-http/3.6.0)
-![Version](https://img.shields.io/badge/rustc-1.68+-ab6000.svg)
+![Version](https://img.shields.io/badge/rustc-1.70+-ab6000.svg)
 ![MIT or Apache 2.0 licensed](https://img.shields.io/crates/l/actix-http.svg)
 <br />
 [![dependency status](https://deps.rs/crate/actix-http/3.6.0/status.svg)](https://deps.rs/crate/actix-http/3.6.0)
@@ -15,11 +15,6 @@
 
 <!-- prettier-ignore-end -->
 
-## Documentation & Resources
-
-- [API Documentation](https://docs.rs/actix-http)
-- Minimum Supported Rust Version (MSRV): 1.68
-
 ## Examples
 
 ```rust

actix-http/benches/date-formatting.rs

@@ -0,0 +1,20 @@
+use std::time::SystemTime;
+
+use actix_http::header::HttpDate;
+use divan::{black_box, AllocProfiler, Bencher};
+
+#[global_allocator]
+static ALLOC: AllocProfiler = AllocProfiler::system();
+
+#[divan::bench]
+fn date_formatting(b: Bencher<'_, '_>) {
+    let now = SystemTime::now();
+
+    b.bench(|| {
+        black_box(HttpDate::from(black_box(now)).to_string());
+    })
+}
+
+fn main() {
+    divan::main();
+}

actix-http/src/date.rs

@@ -28,7 +28,7 @@ impl Date {
 
     fn update(&mut self) {
         self.pos = 0;
-        write!(self, "{}", httpdate::fmt_http_date(SystemTime::now())).unwrap();
+        write!(self, "{}", httpdate::HttpDate::from(SystemTime::now())).unwrap();
     }
 }
 

actix-http/src/header/shared/http_date.rs

@@ -24,8 +24,7 @@ impl FromStr for HttpDate {
 
 impl fmt::Display for HttpDate {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let date_str = httpdate::fmt_http_date(self.0);
-        f.write_str(&date_str)
+        httpdate::HttpDate::from(self.0).fmt(f)
     }
 }
 
@@ -37,7 +36,7 @@ impl TryIntoHeaderValue for HttpDate {
         let mut wrt = MutWriter(&mut buf);
 
         // unwrap: date output is known to be well formed and of known length
-        write!(wrt, "{}", httpdate::fmt_http_date(self.0)).unwrap();
+        write!(wrt, "{}", self).unwrap();
 
         HeaderValue::from_maybe_shared(buf.split().freeze())
     }