Kameo Files

Kameo 0.17 has been released, with some flexibility improvements to the API.

A huge thank you to Huly Labs, Caido Community, vanhouc, cawfeecoder for supporting Kameo's development! 💖

And thanks to our new contributors:

• @Malefaro made their first contribution in [#179]

• @hanekoo made their first contribution in [#163]

• @Avi-D-coder made their first contribution in [#170]

• @artemijan made their first contribution in [#177]

Highlighted Changes

Add Actor::Args associated type and actor spawn methods (#168)

New Actor::Args associated type

A new Args type is added to the Actor trait, allowing the actors state to be initialized in the on_start method.

Unfortunately this makes the on_start method required, since it cannot have a default implementation. But the #[derive(Actor)] macro just sets the Args = Self, and returns the state in the implementation.

Actor spawn methods

The spawn functions have been moved to be part of the Actor trait directly.

This means instead of kameo::spawn(MyActor), you now use MyActor::spawn(MyActor). This looks a little redundant, however the args passed to MyActor::spawn(args) can now be a different type to the actor itself, allowing some powerful patterns.

The spawn methods available are now:

• Actor::spawn
• Actor::spawn_with_mailbox
• Actor::spawn_link
• Actor::spawn_link_with_mailbox
• Actor::spawn_in_thread
• Actor::spawn_in_thread_with_mailbox
• Actor::prepare
• Actor::prepare_with_mailbox

For the methods not suffixed with _with_mailbox, the default mailbox is a bounded with a capacity of 64.

Add Recipient and ReplyRecipient types for type erased actor refs (#160, [#179])

ActorRefs can be "downgraded" into new type erased types Recipient<M> and ReplyRecipient<M, R, E> using the new .recipient() and .reply_recipient() methods.

This allows you to erase the actors type itself, and in exchange have a recipient which can only handle messages of a single type.

New Broker and MessageBus actors

The kameo_actors crate now has two new actors: Broker, and MessageBus.

Add actor shutdown result handling and error hook (#166)

Adds a new wait_for_shutdown_result method to ActorRef, for handling errors during shutdown. Additionally, exposes a kameo::error::set_actor_error_hook function for setting a global function to be called when an actor's on_start or on_stop methods return an error.

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Added

• BREAKING: Add Recipient type for type erased actor refs (#160)
• BREAKING: Add Actor::Args associated type and actor spawn methods (#168)
• Add Recipient and WeakRecipient to prelude
• Add broker actor (#161)
• Add message bus actor (#162)
• Add track_caller to Recipient::tell
• Add actor shutdown result handling and error hook (#166)
• Implement downgrade for Recipient
• Add msg and err methods to SendError (#169)
• Add message_queue actor (#163)
• Add reply recipient that can do ask requests (#179)

Changed

• Wrap large enum variant in Box to fix clippy lint
• Format toml files

Fixed

• Process buffered messages before stopping gracefully
• Actors not stopping due to leaked ActorRef

Misc

• Update criterion requirement from 0.5 to 0.6 (#173)
• Update release script shabangs
• Bump kameo_macros to version 0.17.0

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See the full [CHANGELOG.md](https://github.com/tqwewe/kameo/blob/main/CHANGELOG.md#0170