feat: make settings serializable

Cargo.toml

@@ -55,8 +55,9 @@ tracing = { version = "0.1", default-features = false, features = [
 fnv = "1.0.5"
 slab = "0.4.2"
 indexmap = { version = "2", features = ["std"] }
-smallvec = "1.15.0"
+smallvec = { version = "1.15.0", features = ["serde"] }
 parking_lot = { version = "0.12.4", optional = true }
+serde = { version = "1.0", features = ["derive"] }
 
 [dev-dependencies]
 tracing = { version = "0.1", default-features = false, features = ["std"] }

src/frame/headers.rs

@@ -4,6 +4,8 @@ use crate::frame::{Error, Frame, Head, Kind};
 use crate::hpack::{self, BytesStr};
 use crate::tracing;
 
+use serde::{Deserialize, Serialize};
+
 use http::header::{self, HeaderName, HeaderValue};
 use http::{uri, HeaderMap, Method, Request, StatusCode, Uri};
 
@@ -96,6 +98,40 @@ define_enum_with_values! {
     }
 }
 
+impl Serialize for PseudoId {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        serializer.serialize_str(match self {
+            PseudoId::Method => "METHOD",
+            PseudoId::Scheme => "SCHEME",
+            PseudoId::Authority => "AUTHORITY",
+            PseudoId::Path => "PATH",
+            PseudoId::Protocol => "PROTOCOL",
+            PseudoId::Status => "STATUS",
+        })
+    }
+}
+
+impl<'de> Deserialize<'de> for PseudoId {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let s = String::deserialize(deserializer)?;
+        Ok(match s.as_str() {
+            "METHOD" => PseudoId::Method,
+            "SCHEME" => PseudoId::Scheme,
+            "AUTHORITY" => PseudoId::Authority,
+            "PATH" => PseudoId::Path,
+            "PROTOCOL" => PseudoId::Protocol,
+            "STATUS" => PseudoId::Status,
+            _ => return Err(serde::de::Error::custom("invalid pseudo-header")),
+        })
+    }
+}
+
 /// Represents the order of HTTP/2 pseudo-header fields in a header block.
 ///
 /// This structure maintains an ordered list of pseudo-header fields (such as `:method`, `:scheme`, etc.)
@@ -105,7 +141,7 @@ define_enum_with_values! {
 ///
 /// Typically, a `PseudoOrder` is constructed using the [`PseudoOrderBuilder`] to enforce uniqueness
 /// and protocol-compliant ordering.
-#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+#[derive(Clone, Debug, Hash, PartialEq, Eq, Serialize, Deserialize)]
 pub struct PseudoOrder {
     ids: SmallVec<[PseudoId; PseudoId::DEFAULT_STACK_SIZE]>,
 }

src/frame/priority.rs

@@ -3,13 +3,14 @@ use std::hash::Hash;
 use crate::frame::*;
 use crate::tracing;
 use bytes::BufMut;
+use serde::{Deserialize, Serialize};
 use smallvec::SmallVec;
 
 /// The PRIORITY frame (type=0x2) specifies the sender-advised priority
 /// of a stream [Section 5.3].  It can be sent in any stream state,
 /// including idle or closed streams.
 /// [Section 5.3]: <https://tools.ietf.org/html/rfc7540#section-5.3>
-#[derive(Debug, Clone, Hash, Eq, PartialEq)]
+#[derive(Debug, Clone, Hash, Eq, PartialEq, Serialize, Deserialize)]
 pub struct Priority {
     /// The stream ID of the stream that this priority frame is for
     stream_id: StreamId,
@@ -30,7 +31,7 @@ pub struct Priority {
 /// In HTTP/2, stream dependencies form a dependency tree where each stream
 /// can depend on another stream. This creates a priority hierarchy that helps
 /// determine the relative order in which streams should be processed.
-#[derive(Clone, Copy, Debug, Hash, Eq, PartialEq)]
+#[derive(Clone, Copy, Debug, Hash, Eq, PartialEq, Serialize, Deserialize)]
 pub struct StreamDependency {
     /// The ID of the stream dependency target
     dependency_id: StreamId,
@@ -168,7 +169,7 @@ const DEFAULT_STACK_SIZE: usize = 8;
 /// in HTTP/2. This is useful for pre-configuring stream priorities or
 /// sending multiple PRIORITY frames at once during connection setup or
 /// stream reprioritization.
-#[derive(Debug, Clone, Hash, Eq, PartialEq)]
+#[derive(Debug, Clone, Hash, Eq, PartialEq, Serialize, Deserialize)]
 pub struct Priorities {
     priorities: SmallVec<[Priority; DEFAULT_STACK_SIZE]>,
     max_stream_id: StreamId,

src/frame/settings.rs

@@ -3,6 +3,8 @@ use std::fmt;
 use crate::frame::{util, Error, Frame, FrameSize, Head, Kind, StreamId};
 use crate::tracing;
 use bytes::{BufMut, BytesMut};
+#[cfg(feature = "unstable")]
+use serde::{Deserialize, Serialize};
 use smallvec::SmallVec;
 
 define_enum_with_values! {
@@ -47,6 +49,45 @@ define_enum_with_values! {
     }
 }
 
+impl Serialize for SettingId {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        serializer.serialize_str(match self {
+            SettingId::HeaderTableSize => "HEADER_TABLE_SIZE",
+            SettingId::EnablePush => "ENABLE_PUSH",
+            SettingId::MaxConcurrentStreams => "MAX_CONCURRENT_STREAMS",
+            SettingId::InitialWindowSize => "INITIAL_WINDOW_SIZE",
+            SettingId::MaxFrameSize => "MAX_FRAME_SIZE",
+            SettingId::MaxHeaderListSize => "MAX_HEADER_LIST_SIZE",
+            SettingId::EnableConnectProtocol => "ENABLE_CONNECT_PROTOCOL",
+            SettingId::NoRfc7540Priorities => "NO_RFC7540_PRIORITIES",
+            _ => return Err(serde::ser::Error::custom("invalid setting id")),
+        })
+    }
+}
+
+impl<'de> Deserialize<'de> for SettingId {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let s = String::deserialize(deserializer)?;
+        Ok(match s.as_str() {
+            "HEADER_TABLE_SIZE" => SettingId::HeaderTableSize,
+            "ENABLE_PUSH" => SettingId::EnablePush,
+            "MAX_CONCURRENT_STREAMS" => SettingId::MaxConcurrentStreams,
+            "INITIAL_WINDOW_SIZE" => SettingId::InitialWindowSize,
+            "MAX_FRAME_SIZE" => SettingId::MaxFrameSize,
+            "MAX_HEADER_LIST_SIZE" => SettingId::MaxHeaderListSize,
+            "ENABLE_CONNECT_PROTOCOL" => SettingId::EnableConnectProtocol,
+            "NO_RFC7540_PRIORITIES" => SettingId::NoRfc7540Priorities,
+            _ => return Err(serde::de::Error::custom("invalid setting id")),
+        })
+    }
+}
+
 /// Represents the order of settings in a SETTINGS frame.
 ///
 /// This structure maintains an ordered list of `SettingId` values for use when encoding or decoding
@@ -56,7 +97,7 @@ define_enum_with_values! {
 ///
 /// Typically, a `SettingsOrder` is constructed using the [`SettingsOrderBuilder`] to enforce uniqueness
 /// and protocol-compliant ordering.
-#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+#[derive(Clone, Debug, Hash, PartialEq, Eq, Serialize, Deserialize)]
 pub struct SettingsOrder {
     ids: SmallVec<[SettingId; SettingId::DEFAULT_STACK_SIZE]>,
 }
@@ -138,7 +179,7 @@ impl SettingsOrderBuilder {
 /// Any setting with a standard (known) ID will be ignored and not included in this collection.
 /// This allows for safe experimentation and extension without interfering with standard settings.
 #[cfg(feature = "unstable")]
-#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+#[derive(Clone, Debug, Hash, PartialEq, Eq, Serialize, Deserialize)]
 pub struct ExperimentalSettings {
     settings: SmallVec<[Setting; SettingId::DEFAULT_STACK_SIZE]>,
 }
@@ -244,7 +285,7 @@ pub struct Settings {
 /// frame.
 ///
 /// Each setting has a value that is a 32 bit unsigned integer (6.5.1.).
-#[derive(Debug, Clone, Hash, Eq, PartialEq)]
+#[derive(Debug, Clone, Hash, Eq, PartialEq, Serialize, Deserialize)]
 pub struct Setting {
     id: SettingId,
     value: u32,

src/frame/stream_id.rs

@@ -1,3 +1,5 @@
+use serde::{Deserialize, Serialize};
+
 /// A stream identifier, as described in [Section 5.1.1] of RFC 7540.
 ///
 /// Streams are identified with an unsigned 31-bit integer. Streams
@@ -8,7 +10,7 @@
 /// new stream.
 ///
 /// [Section 5.1.1]: https://tools.ietf.org/html/rfc7540#section-5.1.1
-#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Serialize, Deserialize)]
 pub struct StreamId(u32);
 
 #[derive(Debug, Copy, Clone)]