Swiftpack.co - Package - apple/swift-nio-http2


This project contains HTTP/2 support for Swift projects using SwiftNIO. To get started, check the API docs.


swift-nio-http2 is a SwiftPM project and can be built and tested very simply:

$ swift build
$ swift test


Just like the rest of the SwiftNIO family, swift-nio-http2 follows SemVer 2.0.0 with a separate document declaring SwiftNIO's Public API.

swift-nio-http2 1.x

swift-nio-http2 versions 1.x are a pure-Swift implementation of the HTTP/2 protocol for SwiftNIO. It's part of the SwiftNIO 2 family of repositories and does not have any dependencies besides swift-nio and Swift 5. As the latest version, it lives on the master branch.

To depend on swift-nio-http2, put the following in the dependencies of your Package.swift:

.package(url: "https://github.com/apple/swift-nio-http2.git", from: "1.0.0"),

swift-nio-http2 0.x

The legacy swift-nio-http 0.x is part of the SwiftNIO 1 family of repositories and works on Swift 4.1 and newer but requires nghttp2 to be installed on your system. The source code can be found on the nghttp2-support-branch.

Developing SwiftNIO HTTP/2

For the most part, SwiftNIO development is as straightforward as any other SwiftPM project. With that said, we do have a few processes that are worth understanding before you contribute. For details, please see CONTRIBUTING.md in this repository.


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1.4.0 - Jul 22, 2019

Semver Minor

  • Added support for network-exerted backpressure to HTTP2Channel. (#142)

Semver Patch

  • Fixed an issue where servers sending a PUSH_PROMISE frame before HEADERS would cause streams to be reset. (#145)
  • Fixed an issue where unexpected per-stream frames would crash HTTP2ToHTTP1Codec. (#146)
  • Miscellaneous testing improvements. (#141)

1.3.0 - Jun 19, 2019

Semver Minor

  • Made HTTP2StreamID conform to Strideable. (#133)

Semver Patch

  • Fixed issue where promises for buffered outbound frames could be incorrectly lost when closing connections. (#135)
  • Improved performance by coalescing flushes from child channels in some circumstances. (#132)
  • Improved performance by minimising channelReadComplete calls. (#136)

1.2.1 - May 22, 2019

Semver Patch

  • Fixed an issue where stream channels would not be closed if the underlying transport vanished. (#131)
  • Fixed an issue where flushed frames could very rarely get "stuck" and not emitted until the next flush. (#125)
  • Fixed an issue where flow controlled inbound frames could have their flow control state counted more than once. (#114)
  • Improved performance by removing indirection between stream channels and the stream multiplexer. (#126)
  • Fixed up system for notifying stream channels that they've become active, avoiding issues when setting up such channels. (#124)
  • Correctly notify the outbound frame buffer of changes to the remote peer's value of SETTINGS_MAX_CONCURRENT_STREAMS. (#113)
  • Allow closing idle stream channels that have never been used. (#123)
  • Improved performance by removing unnecessary future callbacks in stream channel setup. (#116)
  • Reduced heap allocations when creating stream channels. (#115)
  • Reduced heap allocations when decoding HPACK header blocks. (#118)
  • Reduced copying when transforming between HTTP/1 and HTTP/2 header blocks. (#112)
  • Removed an inadvertent copy-on-write when buffering inbound frame bytes. (#111)
  • Boxed some cases of HTTP2Frame.FramePayload to avoid the costs of copying the data about. (#110)
  • Improved test setup. (#129, #130)
  • Added allocation tests. (#122)
  • Added performance tests. (#117)
  • Turned on warnings as errors in CI. (#127)

1.2.0 - May 2, 2019

Semver Minor

  • Added support for policing correct content length headers, with support for disabling these checks if needed. (#98)

Semver Patch

  • Fixed an off-by-one error when calculating the valid bounds of certain HTTP/2 settings. (#97)
  • Fixed an issue where we'd incorrectly reject headers that were larger than the dynamic table size, instead of flushing the table. (#99)
  • Fixed an issue where max stream ID was forbidden in GOAWAY when sent by servers. (#102)
  • Removed unnecessary memory copies in the state machine. (#104)
  • Avoided unnecessary heap allocation when parsing frame headers. (#107)
  • Fixed an issue where NIO would consider WINDOW_UPDATE frames on closed streams to be a connection error of type PROTOCOL_ERROR. (#109)
  • Added "Show on Github" link to API docs. (#108)

1.1.0 - Apr 12, 2019

Semver Minor

  • Added additional validation for inbound and outbound HPACK headers. This change adds a number of new errors and a new API to NIOHTTP2Handler to disable this validation. (#84, #90, #91, #94, #95)
  • Rewrote the representation of HPACK headers for a substantial performance improvement. (#89)

Semver Patch

  • Fixed a bug where zero-length SETTINGS frames would be treated as an error. (#88)
  • Substantially decreased the allocation overhead of encoding HTTP headers. (#86)
  • Documentation cleanups. (#82, #82)