modernize ContentLength

actix-web/src/http/header/content_length.rs

@@ -1,8 +1,16 @@
-use super::common_header;
-use crate::http::header;
+use std::{convert::Infallible, str};
 
-common_header! {
-    /// `Content-Length` header, defined in [RFC 7230 §3.3.2].
+use derive_more::{Deref, DerefMut};
+
+use crate::{
+    error::ParseError,
+    http::header::{
+        from_one_raw_str, Header, HeaderName, HeaderValue, TryIntoHeaderValue, CONTENT_LENGTH,
+    },
+    HttpMessage,
+};
+
+/// `Content-Length` header, defined in [RFC 9110 §8.6].
 ///
 /// The Content-Length
 ///
@@ -29,28 +37,202 @@ common_header! {
 ///     .insert_header(ContentLength(3_495));
 /// ```
 ///
-    /// [RFC 7230 §3.3.2]: https://datatracker.ietf.org/doc/html/rfc7230#section-3.3.2
-    (ContentLength, header::CONTENT_LENGTH) => [usize]
+/// [RFC 9110 §8.6]: https://www.rfc-editor.org/rfc/rfc9110#name-content-length
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Deref, DerefMut)]
+pub struct ContentLength(pub usize);
 
-    test_parse_and_format {
-        common_header_test!(no_header, [b""; 0], None);
-        common_header_test!(empty_header, [b""; 1], None);
-
-        common_header_test!(zero, [b"0"], Some(ContentLength(0)));
-        common_header_test!(one, [b"1"], Some(ContentLength(1)));
-        common_header_test!(one_two_three, [b"123"], Some(ContentLength(123)));
-        common_header_test!(
-            thirty_two_power_plus_one,
-            [b"4294967297"],
-            Some(ContentLength(4_294_967_297))
-        );
-        common_header_test!(
-            sixty_four_power_minus_one,
-            [b"18446744073709551615"],
-            Some(ContentLength(18_446_744_073_709_551_615))
-        );
-
-        common_header_test!(invalid1, [b"123,567"], None);
-        common_header_test!(invalid2, [b"123_567"], None);
+impl ContentLength {
+    /// Returns Content-Length value.
+    pub fn into_inner(&self) -> usize {
+        self.0
+    }
+}
+
+impl str::FromStr for ContentLength {
+    type Err = <usize as str::FromStr>::Err;
+
+    #[inline]
+    fn from_str(val: &str) -> Result<Self, Self::Err> {
+        let val = val.trim();
+
+        // decoder prevents this case
+        debug_assert!(!val.starts_with('+'));
+
+        val.parse().map(Self)
+    }
+}
+
+impl TryIntoHeaderValue for ContentLength {
+    type Error = Infallible;
+
+    fn try_into_value(self) -> Result<HeaderValue, Self::Error> {
+        Ok(HeaderValue::from(self.0))
+    }
+}
+
+impl Header for ContentLength {
+    fn name() -> HeaderName {
+        CONTENT_LENGTH
+    }
+
+    fn parse<M: HttpMessage>(msg: &M) -> Result<Self, ParseError> {
+        let val = from_one_raw_str(msg.headers().get(Self::name()))?;
+
+        // decoder prevents multiple CL headers
+        debug_assert_eq!(msg.headers().get_all(Self::name()).count(), 1);
+
+        Ok(val)
+    }
+}
+
+impl From<ContentLength> for usize {
+    fn from(ContentLength(len): ContentLength) -> Self {
+        len
+    }
+}
+
+impl From<usize> for ContentLength {
+    fn from(len: usize) -> Self {
+        ContentLength(len)
+    }
+}
+
+impl PartialEq<usize> for ContentLength {
+    fn eq(&self, other: &usize) -> bool {
+        self.0 == *other
+    }
+}
+
+impl PartialEq<ContentLength> for usize {
+    fn eq(&self, other: &ContentLength) -> bool {
+        *self == other.0
+    }
+}
+
+impl PartialOrd<usize> for ContentLength {
+    fn partial_cmp(&self, other: &usize) -> Option<std::cmp::Ordering> {
+        self.0.partial_cmp(other)
+    }
+}
+
+impl PartialOrd<ContentLength> for usize {
+    fn partial_cmp(&self, other: &ContentLength) -> Option<std::cmp::Ordering> {
+        self.partial_cmp(&other.0)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::fmt;
+
+    use super::*;
+    use crate::{http::header::Header, test::TestRequest, HttpRequest};
+
+    fn req_from_raw_headers<H: Header, I: IntoIterator<Item = V>, V: AsRef<[u8]>>(
+        header_lines: I,
+    ) -> HttpRequest {
+        header_lines
+            .into_iter()
+            .fold(TestRequest::default(), |req, item| {
+                req.append_header((H::name(), item.as_ref().to_vec()))
+            })
+            .to_http_request()
+    }
+
+    #[track_caller]
+    pub(crate) fn assert_parse_fail<
+        H: Header + fmt::Debug,
+        I: IntoIterator<Item = V>,
+        V: AsRef<[u8]>,
+    >(
+        headers: I,
+    ) {
+        let req = req_from_raw_headers::<H, _, _>(headers);
+        H::parse(&req).unwrap_err();
+    }
+
+    #[track_caller]
+    pub(crate) fn assert_parse_eq<
+        H: Header + fmt::Debug + PartialEq,
+        I: IntoIterator<Item = V>,
+        V: AsRef<[u8]>,
+    >(
+        headers: I,
+        expect: H,
+    ) {
+        let req = req_from_raw_headers::<H, _, _>(headers);
+        assert_eq!(H::parse(&req).unwrap(), expect);
+    }
+
+    #[test]
+    fn missing_header() {
+        assert_parse_fail::<ContentLength, _, _>([""; 0]);
+        assert_parse_fail::<ContentLength, _, _>([""]);
+    }
+
+    #[test]
+    fn bad_header() {
+        assert_parse_fail::<ContentLength, _, _>(["-123"]);
+        assert_parse_fail::<ContentLength, _, _>(["123_456"]);
+        assert_parse_fail::<ContentLength, _, _>(["123.456"]);
+
+        // too large for u64 (2^64, 2^64 + 1)
+        assert_parse_fail::<ContentLength, _, _>(["18446744073709551616"]);
+        assert_parse_fail::<ContentLength, _, _>(["18446744073709551617"]);
+
+        // hex notation
+        assert_parse_fail::<ContentLength, _, _>(["0x123"]);
+
+        // multi-value
+        assert_parse_fail::<ContentLength, _, _>(["0, 123"]);
+    }
+
+    #[test]
+    #[should_panic]
+    fn bad_header_plus() {
+        // prevented by HTTP decoder anyway
+        assert_parse_fail::<ContentLength, _, _>(["+123"]);
+    }
+
+    #[test]
+    #[should_panic]
+    fn bad_multiple_value() {
+        // prevented by HTTP decoder anyway
+        assert_parse_fail::<ContentLength, _, _>(["0", "123"]);
+    }
+
+    #[test]
+    fn good_header() {
+        assert_parse_eq::<ContentLength, _, _>(["0"], ContentLength(0));
+        assert_parse_eq::<ContentLength, _, _>(["1"], ContentLength(1));
+        assert_parse_eq::<ContentLength, _, _>(["123"], ContentLength(123));
+
+        // value that looks like octal notation is not interpreted as such
+        assert_parse_eq::<ContentLength, _, _>(["0123"], ContentLength(123));
+
+        // whitespace variations
+        assert_parse_eq::<ContentLength, _, _>([" 0"], ContentLength(0));
+        assert_parse_eq::<ContentLength, _, _>(["0 "], ContentLength(0));
+        assert_parse_eq::<ContentLength, _, _>([" 0 "], ContentLength(0));
+
+        // large value (2^64 - 1)
+        assert_parse_eq::<ContentLength, _, _>(
+            ["18446744073709551615"],
+            ContentLength(18_446_744_073_709_551_615),
+        );
+    }
+
+    #[test]
+    fn equality() {
+        assert!(ContentLength(0) == ContentLength(0));
+        assert!(ContentLength(0) == 0);
+        assert!(0 != ContentLength(123));
+    }
+
+    #[test]
+    fn ordering() {
+        assert!(ContentLength(0) < ContentLength(123));
+        assert!(ContentLength(0) < 123);
+        assert!(0 < ContentLength(123));
     }
 }