HTTP/2 negotiated connection pipeline config

Sources/NIOHTTP2/HTTP2ChannelHandler+InlineStreamMultiplexer.swift

@@ -148,7 +148,7 @@ extension InlineStreamMultiplexer {
         self.commonStreamMultiplexer.createStreamChannel(multiplexer: .inline(self), streamStateInitializer)
     }
 
-    internal func createStreamChannel<Output>(_ initializer: @escaping NIOHTTP2Handler.StreamInitializerWithOutput<Output>) -> EventLoopFuture<Output> {
+    internal func createStreamChannel<Output>(_ initializer: @escaping NIOChannelInitializerWithOutput<Output>) -> EventLoopFuture<Output> {
         self.commonStreamMultiplexer.createStreamChannel(multiplexer: .inline(self), initializer)
     }
 }
@@ -239,7 +239,7 @@ extension NIOHTTP2Handler {
         }
 
         /// Create a stream channel initialized with the provided closure
-        public func createStreamChannel<OutboundStreamOutput>(_ initializer: @escaping NIOHTTP2Handler.StreamInitializerWithOutput<OutboundStreamOutput>) async throws -> OutboundStreamOutput {
+        public func createStreamChannel<OutboundStreamOutput>(_ initializer: @escaping NIOChannelInitializerWithOutput<OutboundStreamOutput>) async throws -> OutboundStreamOutput {
             return try await self.inlineStreamMultiplexer.createStreamChannel(initializer).get()
         }
 
@@ -253,8 +253,8 @@ extension NIOHTTP2Handler {
         @available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
         @_spi(AsyncChannel)
         public func createStreamChannel<Inbound, Outbound>(
-            configuration: NIOAsyncChannel<Inbound, Outbound>.Configuration,
-            initializer: @escaping NIOHTTP2Handler.StreamInitializer
+            configuration: NIOAsyncChannel<Inbound, Outbound>.Configuration = .init(),
+            initializer: @escaping NIOChannelInitializer
         ) async throws -> NIOAsyncChannel<Inbound, Outbound> {
             return try await self.createStreamChannel { channel in
                 initializer(channel).flatMapThrowing { _ in

Sources/NIOHTTP2/HTTP2ChannelHandler.swift

@@ -23,7 +23,6 @@ public let nioDefaultSettings = [
     HTTP2Setting(parameter: .maxHeaderListSize, value: HPACKDecoder.defaultMaxHeaderListSize),
 ]
 
-
 /// ``NIOHTTP2Handler`` implements the HTTP/2 protocol for a single connection.
 ///
 /// This `ChannelHandler` takes a series of bytes and turns them into a sequence of ``HTTP2Frame`` objects.
@@ -988,19 +987,11 @@ extension NIOHTTP2Handler {
 
 extension NIOHTTP2Handler {
 #if swift(>=5.7)
-    /// The type of all `inboundStreamInitializer` callbacks.
-    public typealias StreamInitializer = @Sendable (Channel) -> EventLoopFuture<Void>
-    /// The type of all `connectionInitializer` callbacks.
-    public typealias ConnectionInitializer = @Sendable (Channel) -> EventLoopFuture<Void>
-    /// The type of `inboundStreamInitializer` callbacks which return non-void results.
-    public typealias StreamInitializerWithOutput<Output> = @Sendable (Channel) -> EventLoopFuture<Output>
+    /// The type of all `inboundStreamInitializer` callbacks which do not need to return data.
+    public typealias StreamInitializer = NIOChannelInitializer
 #else
-    /// The type of all `inboundStreamInitializer` callbacks.
-    public typealias StreamInitializer = (Channel) -> EventLoopFuture<Void>
-    /// The type of all `connectionInitializer` callbacks.
-    public typealias ConnectionInitializer = (Channel) -> EventLoopFuture<Void>
-    /// The type of `inboundStreamInitializer` callbacks which return non-void results.
-    public typealias StreamInitializerWithOutput<Output> = (Channel) -> EventLoopFuture<Output>
+    /// The type of all `inboundStreamInitializer` callbacks which need to return data.
+    public typealias StreamInitializer = NIOChannelInitializer
 #endif
 
     /// Creates a new ``NIOHTTP2Handler`` with a local multiplexer. (i.e. using
@@ -1035,6 +1026,9 @@ extension NIOHTTP2Handler {
     }
 
     /// Connection-level configuration.
+    ///
+    /// The settings that will be used when establishing the connection. These will be sent to the peer as part of the
+    /// handshake.
     public struct ConnectionConfiguration: Hashable, Sendable {
         public var initialSettings: HTTP2Settings = nioDefaultSettings
         public var headerBlockValidation: ValidationState = .enabled
@@ -1045,13 +1039,34 @@ extension NIOHTTP2Handler {
     }
 
     /// Stream-level configuration.
+    ///
+    /// The settings that will be used when establishing new streams. These mainly pertain to flow control.
     public struct StreamConfiguration: Hashable, Sendable {
         public var targetWindowSize: Int = 65535
         public var outboundBufferSizeHighWatermark: Int = 8196
         public var outboundBufferSizeLowWatermark: Int = 4092
         public init() {}
     }
 
+    /// Overall connection and stream-level configuration.
+    public struct Configuration: Hashable, Sendable {
+        /// The settings that will be used when establishing the connection. These will be sent to the peer as part of the
+        /// handshake.
+        public var connection: ConnectionConfiguration
+        /// The settings that will be used when establishing new streams. These mainly pertain to flow control.
+        public var stream: StreamConfiguration
+
+        public init() {
+            self.connection = .init()
+            self.stream = .init()
+        }
+
+        public init(connection: ConnectionConfiguration, stream: StreamConfiguration) {
+            self.connection = connection
+            self.stream = stream
+        }
+    }
+
     /// An `EventLoopFuture` which returns a ``StreamMultiplexer`` which can be used to create new outbound HTTP/2 streams.
     ///
     /// > Note: This is only safe to get if the ``NIOHTTP2Handler`` uses a local multiplexer,

Sources/NIOHTTP2/HTTP2CommonInboundStreamMultiplexer.swift

@@ -286,7 +286,7 @@ extension HTTP2CommonInboundStreamMultiplexer {
     internal func _createStreamChannel<Output>(
         _ multiplexer: HTTP2StreamChannel.OutboundStreamMultiplexer,
         _ promise: EventLoopPromise<Output>?,
-        _ streamStateInitializer: @escaping NIOHTTP2Handler.StreamInitializerWithOutput<Output>
+        _ streamStateInitializer: @escaping NIOChannelInitializerWithOutput<Output>
     ) {
         self.channel.eventLoop.assertInEventLoop()
 
@@ -307,7 +307,7 @@ extension HTTP2CommonInboundStreamMultiplexer {
     internal func createStreamChannel<Output>(
         multiplexer: HTTP2StreamChannel.OutboundStreamMultiplexer,
         promise: EventLoopPromise<Output>?,
-        _ streamStateInitializer: @escaping NIOHTTP2Handler.StreamInitializerWithOutput<Output>
+        _ streamStateInitializer: @escaping NIOChannelInitializerWithOutput<Output>
     ) {
         if self.channel.eventLoop.inEventLoop {
             self._createStreamChannel(multiplexer, promise, streamStateInitializer)
@@ -320,7 +320,7 @@ extension HTTP2CommonInboundStreamMultiplexer {
 
     internal func createStreamChannel<Output>(
         multiplexer: HTTP2StreamChannel.OutboundStreamMultiplexer,
-        _ streamStateInitializer: @escaping NIOHTTP2Handler.StreamInitializerWithOutput<Output>
+        _ streamStateInitializer: @escaping NIOChannelInitializerWithOutput<Output>
     ) -> EventLoopFuture<Output> {
         let promise = self.channel.eventLoop.makePromise(of: Output.self)
         self.createStreamChannel(multiplexer: multiplexer, promise: promise, streamStateInitializer)
@@ -426,11 +426,11 @@ internal protocol ChannelContinuation {
 @available(macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0, *)
 struct StreamChannelContinuation<Output>: ChannelContinuation {
     private var continuation: AsyncThrowingStream<Output, Error>.Continuation
-    private let inboundStreamInititializer: NIOHTTP2Handler.StreamInitializerWithOutput<Output>
+    private let inboundStreamInititializer: NIOChannelInitializerWithOutput<Output>
 
     private init(
         continuation: AsyncThrowingStream<Output, Error>.Continuation,
-        inboundStreamInititializer: @escaping NIOHTTP2Handler.StreamInitializerWithOutput<Output>
+        inboundStreamInititializer: @escaping NIOChannelInitializerWithOutput<Output>
     ) {
         self.continuation = continuation
         self.inboundStreamInititializer = inboundStreamInititializer
@@ -446,7 +446,7 @@ struct StreamChannelContinuation<Output>: ChannelContinuation {
     ///   have a `Output` corresponding to that `NIOAsyncChannel` type. Another example is in cases where there is
     ///   per-stream protocol negotiation where `Output` would be some form of `NIOProtocolNegotiationResult`.
     static func initialize(
-        with inboundStreamInititializer: @escaping NIOHTTP2Handler.StreamInitializerWithOutput<Output>
+        with inboundStreamInititializer: @escaping NIOChannelInitializerWithOutput<Output>
     ) -> (StreamChannelContinuation<Output>, NIOHTTP2InboundStreamChannels<Output>) {
         let (stream, continuation) = AsyncThrowingStream.makeStream(of: Output.self)
         return (StreamChannelContinuation(continuation: continuation, inboundStreamInititializer: inboundStreamInititializer), NIOHTTP2InboundStreamChannels(stream))