feat: add cookies

[BorisP1234]

Hello, cookie packets were introduced in Minecraft 1.20.5 along with transfer packets, an underrated feature that can be particularly useful in multi-proxy scenarios. That’s why I found it unfortunate that this functionality wasn’t included in the Gate API, so I decided to add it myself!

I added three functions to the player variable:

• player.CookieStore(key key.Key, payload []byte) error
  This function sends a cookie to the player, storing it even between transfers until the player disconnects. It returns an error if:

  • The key is empty.
  • The payload is too large.
  • The player's state is not "play" or "config."
  • The player is using a version lower than 1.20.5.
  • An error occurs while sending the packet.

• player.CookieRequest(key key.Key) error
  This function requests a cookie from the player. The player then sends a response packet, which can be handled with the PlayerCookieResponseEvent (explained later). It returns an error if:

  • The key is empty.
  • The player is using a version lower than 1.20.5.
  • An error occurs while sending the packet.

• player.CookieRequestWithResult(key key.Key) ([]byte, error)
  This function retrieves a cookie immediately instead of relying on PlayerCookieResponseEvent. It waits for a response from the player for up to 5 seconds. It returns an error if:

  • The key is empty.
  • The player is using a version lower than 1.20.5.
  • An error occurs while sending the packet.
  • The response takes longer than 5 seconds.

I added a new event called PlayerCookieResponseEvent, which listens for cookie response packets. This event contains the player, key, and payload. If the requested cookie is not found, an empty payload is returned.

You can test the features with this wonderful mod that I found called: CookieJar by Tis_awesomeness.

[robinbraemer]

Thank you! I'll try to merge when I find the time

[robinbraemer]

As an afterthought, can we move all public cookie logic into a standalone package? I'm trying to avoid adding more functions to the Player interface. I'm thinking a cookie package similar to https://github.com/minekube/gate/tree/master/pkg/edition/java/bossbar.

[BorisP1234]

Okay I'll take a look at it 👍

[BorisP1234]

Okay I think i managed to resolve every requested change. @robinbraemer Is this how you visioned the cookie package?

The only thing I don't really like is how the CookieResponseEvent doesn't return the Cookie structure, since its not possible due to import cycle. This also made it so I needed to put the map in the proxy package instead of the cookie package but I don't think that is a problem.

[SinonCute]

When this can be merged, I’m waiting for it

[robinbraemer]

There are a few things I have to iterate on.

• thinking ideal interface
• avoid full proxy.Player
• channel handling
• thinking sync Pool is the right choice (there is a potential leak when it is created when doesn’t exist yet)
• testing with varint + writebytes or writebytesraw should be used