Crate micro_traffic_sim

Expand description

§micro_traffic_sim

gRPC interface for microscopic traffic simulation via cellular automata.

This crate provides a tonic-based gRPC client and server for interacting with the micro_traffic_sim_core simulation engine. It allows you to:

Create simulation sessions
Define road networks as cellular grids / graphs
Configure traffic lights with signal phases
Set up conflict zones for unregulated intersections or where traffic lights have conflicting green phases
Setup vehicle generators via trips technique
Step through the simulation and observe vehicle/traffic light states

§Architecture

The simulation core (micro_traffic_sim_core) implements the cellular automaton model for traffic flow. This crate wraps it with a gRPC API defined in Protocol Buffers, enabling language-agnostic access from Go, Python, or any gRPC-compatible client.

§Quick Start (Client)

use micro_traffic_sim::pb::service_client::ServiceClient;
use micro_traffic_sim::pb::{SessionReq, UuiDv4, SessionGrid, Cell, Point};
use tonic::transport::Channel;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Connect to the gRPC server
    let channel = Channel::from_static("http://127.0.0.1:50051")
        .connect()
        .await?;
    let mut client = ServiceClient::new(channel);

    // Create a new session (SRID 0 = Euclidean coordinates)
    let response = client.new_session(SessionReq { srid: 0 }).await?;
    let session_id = response.into_inner().id.unwrap().value;
    println!("Session created: {}", session_id);

    // Now push grid cells, trips, traffic lights, and run simulation steps...
    Ok(())
}

For a complete working example, see examples/rust_client.

§Running the Server

The server binary is included when built with the server feature:

cargo run --features server --bin micro_traffic_sim

§Protocol Buffers

All types are generated from .proto files and exposed under the pb module:

pb::service_client::ServiceClient - gRPC client stub
pb::service_server::ServiceServer - gRPC server trait (with server feature)
pb::Cell - Road network cell
pb::Trip - Vehicle trip/generator configuration
pb::TrafficLight - Traffic light with signal groups
pb::ConflictZone - Priority rules for unregulated intersections
pb::SessionStep / pb::SessionStepResponse - Simulation step request/response
pb::VehicleState - Vehicle position and state per timestep

micro_traffic_sim_core - The computation engine (cellular automaton implementation)

§Clients in Other Languages

Go: clients/go (pkg.go.dev)
Python: clients/python (PyPI)

Re-exports§

pub use pb::*;

Modules§

pb: Generated Protocol Buffer types and gRPC service definitions.