CODESAMPLE

Blackboard - TypeScript

Blackboard TypeScript

The Blackboard pattern is a computational architecture where multiple independent knowledge sources (agents) collaborate to solve a complex problem. A central data structure, the “blackboard,” holds the problem state, and agents react to changes on the blackboard, modifying it to move closer to a solution. This facilitates a flexible and adaptable system, well-suited for problems lacking a clear algorithmic solution.

This TypeScript implementation simulates a simple Blackboard with agents that add information to it. Blackboard class manages the shared data (data). Agent classes each define a run method that examines the blackboard and potentially manipulates the data. Agents are loosely coupled and added to the blackboard instance, triggering their actions when the solve method is called. Using classes and interfaces aligns with TypeScript’s OOP capabilities and promotes type safety and organization.

interface BlackboardData {
  [key: string]: any;
}

class Blackboard {
  private data: BlackboardData = {};
  private agents: Agent[] = [];

  constructor() {}

  getData(): BlackboardData {
    return this.data;
  }

  setData(key: string, value: any) {
    this.data[key] = value;
    this.notifyAgents();
  }

  addAgent(agent: Agent) {
    this.agents.push(agent);
  }

  solve(): void {
    this.agents.forEach(agent => agent.run(this.data, this));
  }

  private notifyAgents(): void {
    this.agents.forEach(agent => agent.run(this.data, this));
  }
}

interface Agent {
  run(data: BlackboardData, blackboard: Blackboard): void;
}

class InputAgent implements Agent {
  run(data: BlackboardData, blackboard: Blackboard): void {
    if (!data.input) {
      console.log("Input Agent: Providing initial input.");
      blackboard.setData("input", "Initial Data");
    }
  }
}

class ProcessingAgent implements Agent {
  run(data: BlackboardData, blackboard: Blackboard): void {
    if (data.input && !data.processed) {
      console.log("Processing Agent: Processing input.");
      blackboard.setData("processed", data.input.toUpperCase());
    }
  }
}

class OutputAgent implements Agent {
  run(data: BlackboardData, blackboard: Blackboard): void {
    if (data.processed) {
      console.log("Output Agent: Displaying result.");
      console.log("Result:", data.processed);
    }
  }
}

// Example Usage:
const blackboard = new Blackboard();
blackboard.addAgent(new InputAgent());
blackboard.addAgent(new ProcessingAgent());
blackboard.addAgent(new OutputAgent());

blackboard.solve();