HTTP/3 support

[vietj]

Roadmap

5.1

• configuration
• implementation
  • outer context integration and testing
  • metrics
  • tracing
  • send file
  • network activity logging
  • H3 alternative services implementation
    • alternative services decoding
      • HTTP/1.1 alt-svc header support
      • HTTP/2 alt-svc frame support
    • Alternative services client support
  • HTTP/3 datagrams
  • following alternative services should be enabled for short names and force SNI
  • quic datagram event handling fix
  • Client hostname verification
  • Server alt-svc notifications
  • Synchronous SNI mapping to certificates
  • Endpoint certificate update
  • Server load balancing
• API
  • breaking changes
    • HTTP settings
    • Stream ids
  • Deprecations
    • Stream reset in favor of cancellation
    • Connection go away in favor of shutdown
  • dev
    • options
    • connection close payload
• Improve Netty Quic reset
• Netty HTTP/3 frame logging
• go away strategies ?
• documentation
• ...

5.x

• Compression
• DNS HTTPS resource record
• Connect UDP
• Datagrams
• Netty should emit an event when sender remote address changes
• push ?
  • client
  • server

Breaking changes

Implementing HTTP/3 implies a few potential breaking changes, the strategy to handle them will be on a case by case basis and attempt to minimize the amount of breaking changes to delay them until Vert.x 6 is implemented, here is a non exhaustive list:

• stream id declares long type instead of int
• settings
• ...

Open concerns

Compression

There is no facility for payload compression and current one for HTTP/1 and HTTP/2 are not reusable.

Discovery

No support for HTTPS resource records in DNS resolver, this will be implemented in 5.0 using alternative services.

Shutdown / GoAway

• H2: GoAway carries stream id + error code + debug data
• H3: GoAway only carries stream id, but quic can close with an error code + reason data, error code seems similar but reason is not the same semantic than debug.

Reset semantic

• H2: reset means immediate termination of a stream
• H3: reset only applies to the stream outbound and means no more data will be set

Introduce stream cancellation that performs the most adapted operation according to the protocol:

• H2 : reset with 0x8 (CANCEL) code
• H3 : reset or abort reading with REQUEST_CANCELLED code

Keep alive timeout semantic

• HTTP/1.1 / H2: connection level
• H3: stream level

Contribution

bibi