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Messages

Bases: BaseModel, Generic[T]

Messages

Message class is the base class for all of the messages passing through the channels. It is a pydantic BaseModel with a single field data containing the actual data. The data field is a subclass of aact.messages.DataModel.

Usage

To create a message type with DataModel T, you can use Message[T]. To initialize a message, you can use Message[T](data=your_data_model_instance).

Why have an additional wrapper over DataModel? The reason for having a separate class for messages is to leverage the [pydantic's tagged union feature](https://docs.pydantic.dev/latest/concepts/performance/#use-tagged-union-not-union). This allows us to differentiate between different message types at runtime. For example, the following code snippet shows how to decide the message type at runtime: 
from aact import Message, DataModel
from aact.messages import Image, Tick

tick = 123
tick_message = Message[Tick](data=Tick(tick=tick))
tick_message_json = tick_message.model_dump_json()

possible_image_or_tick_message = Message[Tick | Image].model_validate_json(
    tick_message_json
)
assert isinstance(possible_image_or_tick_message.data, Tick)

data class-attribute instance-attribute 

data: T = Field(discriminator='data_type')

@private

Bases: BaseModel

DataModel

A datamodel in aact is a pydantic BaseModel with an additional field data_type to differentiate between different message types.

Here are the built-in data models:

  • aact.message.Tick: A data model with a single field tick of type int. This is useful for sending clock ticks.
  • aact.messages.Float: A data model with a single field value of type float. This is useful for sending floating-point numbers.
  • aact.messages.Image: A data model with a single field image of type bytes. This is useful for sending images.
  • aact.messages.Text: A data model with a single field text of type str. This is useful for sending text messages.
  • aact.messages.Audio: A data model with a single field audio of type bytes. This is useful for sending audio files.
  • aact.messages.Zero: A dummy data model with no fields. This is useful when the nodes do not receive or send any data.

Customize DataModels

For custimizing your own data models, here is an example:


from aact.messages import DataModel, DataModelFactory


@DataModelFactory.register("my_data_model")
class MyDataModel(DataModel):
    my_field: str

You can see that you don't need to define the data_type field in your custom data models. The DataModelFactory will take care of it for you.

data_type class-attribute instance-attribute 

data_type: Literal[''] = Field('')

@private