Azure functions

.NET is a software framework developed by Microsoft that runs primarily on Microsoft Windows. It includes an extensive library of pre-written code and provides a runtime environment for executing code written in various programming languages. The framework is designed to provide a consistent object-oriented programming environment, whether code is executed on a server, browser, or desktop. It also includes a standard set of libraries for tasks such as connecting to databases, creating graphical user interfaces, and handling security.

Traceable provides a .NET agent to capture the requests inline. If, for some reason, Traceable cannot capture the request, the requests are passed through to the application. The following is a high-level deployment diagram:

Before you begin

Make a note of the following before proceeding with Traceable’s .NET agent configuration:

• Make sure that the Traceable Platform agent is already installed. For more information on installation, see Platform agent.

• Make a note of the Traceable Platform agent IP address. This would be used in configuration later.

• Decide on a service name. This is required during configuration and is displayed in the Traceable Platform.

• Traceable supports Azure Function with HTTP Trigger template v4 running on .NET 6 on .NET agent.

Supported framework

Traceable’s .NET agent supports Azure Functions. In the context of the Azure function, there are two different runtimes: In-process and isolated.

• In-Process (or In-Process Worker): In this model, the Azure Functions runtime is hosted within the same process as the Azure Functions host. This means that the functions run within the same runtime process, which provides better performance and reduced latency compared to the isolated model. In-process hosting is suitable for scenarios where performance is critical, such as high-throughput applications or functions with low latency requirements.

• Isolated (or Out-of-Process Worker): In the isolated model, each function runs within its own separate process, isolated from the Azure Functions host. This provides greater flexibility and scalability, as each function can have its runtime environment, including support for different programming languages and frameworks. Isolated hosting is suitable for scenarios where you need to run functions in languages other than those natively supported by the Azure Functions host or when you need to control the runtime environment more precisely.

Traceable supports In-process runtime. Along with In-process runtime, Traceable supports HTTP Trigger template. The HTTP Trigger template is a type of Azure Functions template that allows you to create functions that respond to HTTP requests. When you create an Azure Function using the HTTP Trigger template, you are essentially creating an endpoint that can be invoked via HTTP.

Configuration

Complete the following steps to configure Traceable’s .NET agent with Azure Functions:

1. Add the Traceable.Agent package to the project from NuGet gallery.

   dotnet add package Traceable.Agent

2. In the Azure portal, navigate to your project’s root directory and make the following code change to startup.cs file. In Azure Functions projects, the startup.cs file is a crucial component responsible for configuring the application's services and request processing pipeline. It's typically located in the project's root directory.

   using Microsoft.AspNetCore.Server.Kestrel;
   using Microsoft.Azure.Functions.Extensions.DependencyInjection;
   using Microsoft.Extensions.DependencyInjection;
   using Traceable; //<- additional change for Traceable
   
   [assembly: FunctionsStartup(typeof(Company.Function.Startup))]
   namespace Company.Function
   {
       public class Startup : FunctionsStartup
       {
           public override void Configure(IFunctionsHostBuilder builder)
           {
               // changes for traceable begin
               var traceableAgent = TraceableAgentBuilder.CreateBuilder()
               .AddInstrumentation(Instrumentations.AzureFunctionsInProcess)
               .Build();
               builder.Services.AddSingleton(traceableAgent);
               // changes for traceable end
               
               builder.Services.AddLogging();
           }
       }
   }

   Make a note of the code that you need to insert:

   // changes for traceable begin
               var traceableAgent = TraceableAgentBuilder.CreateBuilder()
               .AddInstrumentation(Instrumentations.AzureFunctionsInProcess)
               .Build();
               builder.Services.AddSingleton(traceableAgent);
   // changes for traceable end

   Note

   If you are not using the above class, you can create one by referring to Microsoft documentation.

3. Add the following environment variables for configuration. In your Azure function application, navigate to Settings → Configuration to add the environment variable and save the configuration.

   

   ---

   Environment variable	Description
   TA_SERVICE_NAME	The name with which you would like to identify the service in Traceable Platform.
   TA_REPORTING_ENDPOINT	The endpoint for reporting the traces. OTLP - For OTLP reporter, use http://api.traceable.ai:4317
   TA_DATA_CAPTURE_HTTP_HEADERS_REQUEST	When set to false, the agent disables request capturing.
   TA_DATA_CAPTURE_HTTP_HEADERS_RESPONSE	When set to false, the agent disables response capturing.
   TA_DATA_CAPTURE_HTTP_BODY_REQUEST	When set to false, the agent disables request body capturing.
   TA_DATA_CAPTURE_HTTP_BODY_RESPONSE	When set to false, the agent disables response body capturing.
   TA_DATA_CAPTURE_BODY_MAX_SIZE_BYTES	Configure the maximum size of the body to capture. The default value is 128 KiB.
   TA_DATA_CAPTURE_ALLOWED_CONTENT_TYPES	Comma-separated values of content type to capture. The default is [json, x-www-form-urlencoded]. For example, [json] will record any request body that has a content-type header that includes “json”.
   TA_ENABLED	Set it to false, if you wish to disable Traceable’s .NET agent.
   TA_TELEMETRY_STARTUP_SPAN_ENABLED	When set to true, an internal span is created and exported when the agent is initialized and started.

4. Deploy the application to Azure.

Verification

Send data to your application. On successful configuration, you will see Span data in the Traceable Platform.

Upgrade

Complete the following steps to upgrade the package:

1. Enter the following command to upgrade:

   dotnet add package Traceable.Agent

2. Deploy the application to Azure.

Uninstall

Complete the following steps to uninstall the .NET agent:

1. Remove the .NET agent bootstrap code from startup.cs file.

2. Remove the Traceable.Agent package dependency from the project csproj file. Following is an example of csproj file. Remove <PackageReference Include="Traceable.Agent" Version="1.0.0-rc.5" /> from csproj file.

   <Project Sdk="Microsoft.NET.Sdk">
     <PropertyGroup>
       <TargetFramework>net6.0</TargetFramework>
       <AzureFunctionsVersion>v4</AzureFunctionsVersion>
       <RootNamespace>azure_app_inprocess</RootNamespace>
     </PropertyGroup>
     <ItemGroup>
       <PackageReference Include="Microsoft.AspNetCore.Hosting" Version="2.2.7" />
       <PackageReference Include="Microsoft.AspNetCore.Http" Version="2.2.2" />
       <PackageReference Include="Microsoft.AspNetCore.Http.Features" Version="5.0.17" />
       <PackageReference Include="Microsoft.Azure.Functions.Extensions" Version="1.1.0" />
       <PackageReference Include="Microsoft.Azure.WebJobs" Version="3.0.39" />
       <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.EventHubs" Version="6.0.2" />
       <PackageReference Include="Microsoft.NET.Sdk.Functions" Version="4.2.0" />
       <PackageReference Include="System.Reactive.Core" Version="6.0.0" />
       <PackageReference Include="Microsoft.AspNetCore.Http.Extensions" Version="2.2.0" />
       <PackageReference Include="Microsoft.IO.RecyclableMemoryStream" Version="3.0.0" />
       <PackageReference Include="Microsoft.AspNetCore.Http.Features" Version="5.0.17" />
       <PackageReference Include="Traceable.Agent" Version="1.0.0-rc.5" />
     </ItemGroup>
     <ItemGroup>
       <None Update="host.json">
         <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
       </None>
       <None Update="local.settings.json">
         <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
         <CopyToPublishDirectory>Never</CopyToPublishDirectory>
       </None>
     </ItemGroup>
   </Project>

3. Perform a dotnet restore.

   dotnet restore

4. Deploy the application to Azure.