agent-framework/dotnet/samples/04-hosting/DurableWorkflows/ConsoleApps/03_ConditionalEdges

Conditional Edges Workflow Sample

This sample demonstrates how to build a workflow with conditional edges that route execution to different paths based on runtime conditions. The workflow evaluates conditions on the output of an executor to determine which downstream executor to run.

Key Concepts Demonstrated

• Building workflows with conditional edges using AddEdge with a condition parameter
• Defining reusable condition functions for routing logic
• Branching workflow execution based on data-driven decisions
• Using ConfigureDurableWorkflows to register workflows with dependency injection

Overview

The sample implements an order audit workflow that routes orders differently based on whether the customer is blocked (flagged for fraud):

OrderIdParser --> OrderEnrich --[IsBlocked]--> NotifyFraud
                              |
                              +--[NotBlocked]--> PaymentProcessor

Executor	Description
OrderIdParser	Parses the order ID and retrieves order details
OrderEnrich	Enriches the order with customer information
PaymentProcessor	Processes payment for valid orders
NotifyFraud	Notifies the fraud team for blocked customers

How Conditional Edges Work

Conditional edges allow you to specify a condition function that determines whether the edge should be traversed:

builder
    .AddEdge(orderParser, orderEnrich)
    .AddEdge(orderEnrich, notifyFraud, condition: OrderRouteConditions.WhenBlocked())
    .AddEdge(orderEnrich, paymentProcessor, condition: OrderRouteConditions.WhenNotBlocked());

The condition functions receive the output of the source executor and return a boolean:

internal static class OrderRouteConditions
{
    // Routes to NotifyFraud when customer is blocked
    internal static Func<Order?, bool> WhenBlocked() => 
        order => order?.Customer?.IsBlocked == true;

    // Routes to PaymentProcessor when customer is not blocked
    internal static Func<Order?, bool> WhenNotBlocked() => 
        order => order?.Customer?.IsBlocked == false;
}

Routing Logic

In this sample, the routing is based on the order ID:

• Order IDs containing the letter 'B' are associated with blocked customers → routed to NotifyFraud
• All other order IDs are associated with valid customers → routed to PaymentProcessor

Environment Setup

See the README.md file in the parent directory for information on configuring the environment, including how to install and run the Durable Task Scheduler.

Running the Sample

cd dotnet/samples/04-hosting/DurableWorkflows/ConsoleApps/03_ConditionalEdges
dotnet run --framework net10.0

Sample Output

Valid order (routes to PaymentProcessor):

Enter an order ID (or 'exit'):
> 12345
Starting workflow for order '12345'...
Run ID: abc123...
Waiting for workflow to complete...
Workflow completed. {"Id":"12345","Amount":100.0,"Customer":{"Id":201,"Name":"Jerry","IsBlocked":false},"PaymentReferenceNumber":"a1b2"}

Blocked order (routes to NotifyFraud):

Enter an order ID (or 'exit'):
> 12345B
Starting workflow for order '12345B'...
Run ID: def456...
Waiting for workflow to complete...
Workflow completed. Order 12345B flagged as fraudulent for customer George.