Implement the extended CONNECT protocol from RFC 8441 (#565)

src/ext.rs

@@ -0,0 +1,55 @@
+//! Extensions specific to the HTTP/2 protocol.
+
+use crate::hpack::BytesStr;
+
+use bytes::Bytes;
+use std::fmt;
+
+/// Represents the `:protocol` pseudo-header used by
+/// the [Extended CONNECT Protocol].
+///
+/// [Extended CONNECT Protocol]: https://datatracker.ietf.org/doc/html/rfc8441#section-4
+#[derive(Clone, Eq, PartialEq)]
+pub struct Protocol {
+    value: BytesStr,
+}
+
+impl Protocol {
+    /// Converts a static string to a protocol name.
+    pub const fn from_static(value: &'static str) -> Self {
+        Self {
+            value: BytesStr::from_static(value),
+        }
+    }
+
+    /// Returns a str representation of the header.
+    pub fn as_str(&self) -> &str {
+        self.value.as_str()
+    }
+
+    pub(crate) fn try_from(bytes: Bytes) -> Result<Self, std::str::Utf8Error> {
+        Ok(Self {
+            value: BytesStr::try_from(bytes)?,
+        })
+    }
+}
+
+impl<'a> From<&'a str> for Protocol {
+    fn from(value: &'a str) -> Self {
+        Self {
+            value: BytesStr::from(value),
+        }
+    }
+}
+
+impl AsRef<[u8]> for Protocol {
+    fn as_ref(&self) -> &[u8] {
+        self.value.as_ref()
+    }
+}
+
+impl fmt::Debug for Protocol {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.value.fmt(f)
+    }
+}