Composable Attribute System

Runtime composition of VRP features without inheritance hierarchies.

Quick Start

Python

import routing
from routing.constants import Attribute

routing.init()

problem = routing.Problem()

# Depot
depot = problem.add_depot(0)
depot.add_attribute(Attribute.GEONODE, x=0, y=0)
depot.add_attribute(Attribute.RENDEZVOUS, open=0, close=1000)

# Vehicles
for v in range(3):
    vehicle = problem.add_vehicle(v)
    vehicle.add_attribute(Attribute.STOCK, capacity=100)

# Clients
client = problem.add_client(1)
client.add_attribute(Attribute.GEONODE, x=10, y=20)
client.add_attribute(Attribute.CONSUMER, demand=15)
client.add_attribute(Attribute.RENDEZVOUS, open=50, close=200)
client.add_attribute(Attribute.SERVICE_QUERY, service_time=10)

# Solve (constraints auto-activated!)
solution = routing.solve(problem, "ga", timeout=30)

C++

#include <routing/routing.hpp>

int main() {
    routing::Problem problem;

    // Depot
    auto* depot = problem.addDepot(0);
    depot->addAttribute<routing::attributes::GeoNode>(0.0, 0.0);
    depot->addAttribute<routing::attributes::Rendezvous>(0, 1000);

    // Vehicles
    for (int v = 0; v < 3; ++v) {
        auto* vehicle = problem.addVehicle(v);
        vehicle->addAttribute<routing::attributes::Stock>(100);
    }

    // Clients
    auto* client = problem.addClient(1);
    client->addAttribute<routing::attributes::GeoNode>(10.0, 20.0);
    client->addAttribute<routing::attributes::Consumer>(15);
    client->addAttribute<routing::attributes::Rendezvous>(50, 200);
    client->addAttribute<routing::attributes::ServiceQuery>(10);

    // Solve
    routing::GASolver solver(&problem);
    solver.solve(30.0);

    return 0;
}

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Available Attributes

Attribute	Entity	Description
GeoNode	Any	Coordinates (x, y)
Consumer	Client	Demand
Stock	Vehicle	Capacity
Rendezvous	Any	Time window (open, close)
ServiceQuery	Client	Service time
Profiter	Client	Profit (TOP)
Pickup	Client	Pickup demand
Delivery	Client	Delivery demand
Synced	Client	Synchronization

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Problem Types

Problem	Attributes
TSP	GeoNode
CVRP	GeoNode, Consumer, Stock
VRPTW	GeoNode, Rendezvous, ServiceQuery
CVRPTW	GeoNode, Consumer, Stock, Rendezvous, ServiceQuery
TOP	GeoNode, Profiter, Rendezvous
PDVRP	GeoNode, Pickup, Delivery, Stock

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How It Works

1. Add attributes to entities

2. Constraints auto-activate based on attributes:

   • GeoNode → Routing/distance

   • Consumer + Stock → Capacity constraints

   • Rendezvous → Time windows

3. Solve with any solver

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Custom Attributes (C++)

// Define attribute
struct MyAttribute : public Attribute<MyAttribute> {
    double value;
    explicit MyAttribute(double v) : value(v) {}
};

// Use it
client->addAttribute<MyAttribute>(42.0);

See Plugins for full custom attribute guide.