Module channels

Expand description

Generates all channels used by the application. Defines and constructs the entire inter-thread communication infrastructure for the application.

This module serves as the central nervous system of the aquarium controller. It is responsible for two primary tasks:

Defining Channel Wrappers: It provides AquaSender and AquaReceiver, which are custom wrappers around std::sync::mpsc channels. These wrappers add optional debugging capabilities.
Constructing the Communication Graph: The Channels::build method instantiates every single channel required for the application’s threads to communicate. It then bundles them into the main Channels struct.

AquaSender / AquaReceiver: These wrappers provide a consistent channel interface. When the debug_channels feature is enabled, they use bounded sync_channels and count the number of messages sent and received. In release builds, they compile down to lightweight wrappers around standard, unbounded channels.
Channels Struct: A struct that aggregates all the individual ...Channels structs (e.g., FeedChannels, RelayManagerChannels). This provides a single, clean object that can be used to distribute the correct channel endpoints to each thread at startup.
Channels::build(): This is the most critical function in the module. It contains the complete “wiring diagram” of the application. It creates all bidirectional and unidirectional channels, carefully handling conditional compilation for features like the IPC messaging system (on Linux) and various simulators used during testing.

Centralized Construction: By creating every channel in one place, this module acts as a single source of truth for the application’s communication topology. Any change to inter-thread communication can be understood by looking at this file.
Decoupling via Aggregation: Modules like feed or refill don’t need to know about the entire system’s channel graph. They are simply given their own small FeedChannels or RefillChannels struct, which contains only the endpoints they care about. This dramatically reduces coupling between modules.
Compile-Time Flexibility: The extensive use of #[cfg] attributes allows the communication graph to be adapted at compile time. For example, channels to the TcpCommunication simulator are only created and wired up if a simulator is enabled, and IPC channels are only created on Linux.

Macros§

create_bidirectional_channel 🔒: Creates a pair of bidirectional channels for request/response communication.
create_unidirectional_channel 🔒: Creates a channel for one-way communication.