Building and Deploying Azure Functions in .NET/

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Durable Functions Orchestration Basics

Durable Functions Orchestration Basics

Learn the fundamentals of the orchestration process in Azure Durable Functions.

We'll cover the following...

In this lesson, we will have a look at how the orchestration process works in Durable Functions. We will do so with the help of the interactive playground below:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
    <AzureFunctionsVersion>v4</AzureFunctionsVersion>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.DurableTask" Version="2.9.2" />
    <PackageReference Include="Microsoft.NET.Sdk.Functions" Version="4.1.1" />
  </ItemGroup>
  <ItemGroup>
    <None Update="host.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
    </None>
    <None Update="local.settings.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
      <CopyToPublishDirectory>Never</CopyToPublishDirectory>
    </None>
  </ItemGroup>
</Project>
Durable function example

In this setup, we have a simple HTTP trigger that starts the orchestrator. The orchestrator then triggers a basic activity function that returns a message based on its input.

Starting the orchestrator

When the trigger function starts the orchestrator, behind the scenes, a message is placed on a queue in the Azure Storage Account. This is why we need access to a Storage Account for a durable function to work.

In the example above, we start the orchestrator in line 35 of the Functions.cs file, which looks like this:

string instanceId = await starter.StartNewAsync("Function", null);
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