RFlow
Chat-like HMI for embedded Rust applications and PLCs
RFlow is a part of [RoboPLC](https://www.roboplc.com) project.
## The idea
Many of embedded applications and PLC programs do not have any human-machine
interface and not supposed to have one by design.
However, sometimes it is very useful to have a simple way to interact with the
application, e.g. for debugging purposes or having a basic emergency interface
in production.
RFlow provides the most possible lightweight way to have a chat-like interface
between the application (server) and its clients, which does not affect the
application real-time run-flow and consumes minimal system resources.
The [RFlow protocol](https://github.com/roboplc/rflow/blob/main/protocol.md) is
fully text-based and can be used with no special client.
## Clients
* [RFlow Chat](https://crates.io/crates/rflow-chat) - a dedicated RFlow chat
client (terminal).
* Custom clients, built with the crate `Client` API.
* Any terminal TCP client, e.g. `telnet`, `nc`.
## A very basic example
```rust,no_run
use std::{thread, time::Duration};
use rtsc::time::interval;
fn main() -> Result<(), Box> {
let data_channel = rflow::take_data_channel()?;
thread::spawn(move || {
rflow::serve("127.0.0.1:4001").expect("failed to start server");
});
thread::spawn(move || {
for _ in interval(Duration::from_secs(5)) {
rflow::send("ping".to_string());
}
});
for data in data_channel {
println!("Received data: {}", data);
rflow::send(format!("command accepted: {}", data));
let command = data.trim();
if command == "quit" {
break;
}
}
Ok(())
}
```