Phobos 2.0 Quickstart Tutorial

This tutorial will help you understand how to configure and install Phobos inside an Akka.NET v1.4+ application.

Note

Need the Phobos 1.x Quickstart Tutorial? Click here.

Note

For this quickstart tutorial, we're going to clone the Petabridge.Phobos.Web repository from Github and run it.

This project is a ready-made solution for testing Phobos in a real production environment using the following technologies:

Video Overview

If you want to get a gist of how the installation process works, you can follow the video from our Phobos Installation Tutorial below.

For further reading, please also see "Phobos Configuration".

Note

The Phobos QuickStart Tutorial also uses the "Phobos + Prometheus Akka.Cluster Dashboard for Grafana," which can immediately visualize your Phobos data inside Grafana when you're using Prometheus (which this demo does.) You should check it out along with the other Phobos dashboards.

Build and Local Deployment

Start by cloning this repository to your local system.

Next - to build this solution you will need to purchase a Phobos license key. They cost $4,000 per year per organization with no node count or seat limitations and comes with a 30 day money-back guarantee.

Once you purchase a Phobos NuGet keys for your organization, you're going to want to open NuGet.config and add your key:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <solution>
    <add key="disableSourceControlIntegration" value="true" />
  </solution>
  <packageSources>
    <clear />
    <add key="nuget.org" value="https://api.nuget.org/v3/index.json" />
    <add key="phobos" value="{your key here}" />
  </packageSources>
</configuration>

From there, run the following commad on the prompt:

PS> build.cmd Docker

This will create the Docker images the solution needs to run inside Kubernetes: petabridge.phobos.web:0.1.0.

Deploying the K8s Cluster (with Telemetry Installed)

From there, everything you need to run the solution in Kubernetes is already defined inside the k8s/ - just run the following command to launch the Phobos-enabled application inside Kubernetes:

PS> ./k8s/deployAll.cmd

This will spin up a separate Kubernetes namespace, phobos-web, and you can view which services are deployed by running the following command:

PS> kubectl get all -n phobos-web

You should see the following or similar output:

NAME                                        READY   STATUS    RESTARTS   AGE
pod/grafana-5f54fd5bf4-wvdgw                1/1     Running   0          11m
pod/jaeger-578558d6f9-2xzdv                 1/1     Running   0          11m
pod/phobos-web-0                            1/1     Running   3          11m
pod/phobos-web-1                            1/1     Running   2          10m
pod/phobos-web-2                            1/1     Running   0          9m54s
pod/prometheus-deployment-c6d99b8b9-28tmq   1/1     Running   0          11m

NAME                            TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)                               AGE
service/grafana-ip-service      LoadBalancer   10.105.46.6      localhost     3000:31641/TCP                        11m
service/jaeger-agent            ClusterIP      None             <none>        5775/UDP,6831/UDP,6832/UDP,5778/TCP   11m
service/jaeger-collector        ClusterIP      10.109.248.20    <none>        14267/TCP,14268/TCP,9411/TCP          11m
service/jaeger-query            LoadBalancer   10.109.204.203   localhost     16686:30911/TCP                       11m
service/phobos-web              ClusterIP      None             <none>        4055/TCP                              11m
service/phobos-webapi           LoadBalancer   10.103.247.68    localhost     1880:30424/TCP                        11m
service/prometheus-ip-service   LoadBalancer   10.101.119.120   localhost     9090:31698/TCP                        11m
service/zipkin                  ClusterIP      None             <none>        9411/TCP                              11m

NAME                                    READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/grafana                 1/1     1            1           11m
deployment.apps/jaeger                  1/1     1            1           11m
deployment.apps/prometheus-deployment   1/1     1            1           11m

NAME                                              DESIRED   CURRENT   READY   AGE
replicaset.apps/grafana-5f54fd5bf4                1         1         1       11m
replicaset.apps/jaeger-578558d6f9                 1         1         1       11m
replicaset.apps/prometheus-deployment-c6d99b8b9   1         1         1       11m
Note

The restarts from the phobos-web-* pods come from calling Dns.GetHostName() prior to the local K8s service allocating its hostnames. Nothing to worry about - it'll resolve itself in a few moments.

Once the cluster is fully up and running you can explore the application and its associated telemetry via the following Urls:

There's many more metrics exported by Phobos that you can use to create your own dashboards or extend the existing ones - you can view all of them by going to http://localhost:1880/metrics

Looking at the Code

So we can poke around and play with the solution now, but where's the real code?

It's all located inside the Startup.cs class.

    public class Startup
    {
        /// <summary>
        ///     Name of the <see cref="Environment" /> variable used to direct Phobos' Jaeger
        ///     output.
        ///     See https://github.com/jaegertracing/jaeger-client-csharp for details.
        /// </summary>
        public const string JaegerAgentHostEnvironmentVar = "JAEGER_AGENT_HOST";

        public const string JaegerEndpointEnvironmentVar = "JAEGER_ENDPOINT";

        public const string JaegerAgentPortEnvironmentVar = "JAEGER_AGENT_PORT";

        public const int DefaultJaegerAgentPort = 6832;

        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
            // Prometheus exporter won't work without this
            services.AddControllers();

            var resource = ResourceBuilder.CreateDefault()
                .AddService(Assembly.GetEntryAssembly().GetName().Name, serviceInstanceId: $"{Dns.GetHostName()}");

            // enables OpenTelemetry for ASP.NET / .NET Core
            services.AddOpenTelemetryTracing(builder =>
            {
                builder
                    .SetResourceBuilder(resource)
                    .AddPhobosInstrumentation()
                    .AddSource("Petabridge.Phobos.Web")
                    .AddHttpClientInstrumentation(options =>
                    {
                        // don't trace HTTP output to Seq
                        options.Filter = httpRequestMessage => !httpRequestMessage.RequestUri.Host.Contains("seq");
                    })
                    .AddAspNetCoreInstrumentation(options =>
                    {
                        options.Filter = context => !context.Request.Path.StartsWithSegments("/metrics");
                    })
                    .AddJaegerExporter(opt =>
                    {
                        opt.AgentHost = Environment.GetEnvironmentVariable(JaegerAgentHostEnvironmentVar);
                    });
            });

            services.AddOpenTelemetryMetrics(builder =>
            {
                builder
                    .SetResourceBuilder(ResourceBuilder.CreateDefault()
                        .AddService(Assembly.GetEntryAssembly().GetName().Name,
                            serviceInstanceId: $"{Dns.GetHostName()}"))
                    .AddPhobosInstrumentation()
                    .AddHttpClientInstrumentation()
                    .AddAspNetCoreInstrumentation()
                    .AddPrometheusExporter(opt => { });
            });

            // sets up Akka.NET
            ConfigureAkka(services);
        }

        public static void ConfigureAkka(IServiceCollection services)
        {
            services.AddAkka("ClusterSys", (builder, provider) =>
            {
                // use our legacy app.conf file
                var config = ConfigurationFactory.ParseString(File.ReadAllText("app.conf"))
                    .BootstrapFromDocker()
                    .UseSerilog();

                builder.AddHocon(config)
                    .WithClustering(new ClusterOptions { Roles = new[] { "console" } })
                    .WithPhobos(AkkaRunMode.AkkaCluster) // enable Phobos
                    .StartActors((system, registry) =>
                    {
                        var consoleActor = system.ActorOf(Props.Create(() => new ConsoleActor()), "console");
                        var routerActor = system.ActorOf(Props.Empty.WithRouter(FromConfig.Instance), "echo");
                        var routerForwarderActor =
                            system.ActorOf(Props.Create(() => new RouterForwarderActor(routerActor)), "fwd");
                        registry.TryRegister<RouterForwarderActor>(routerForwarderActor);
                    })
                    .StartActors((system, registry) =>
                    {
                        // start https://cmd.petabridge.com/ for diagnostics and profit
                        var pbm = PetabridgeCmd.Get(system); // start Pbm
                        pbm.RegisterCommandPalette(ClusterCommands.Instance);
                        pbm.RegisterCommandPalette(new RemoteCommands());
                        pbm.Start(); // begin listening for PBM management commands
                    });
            });
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment()) app.UseDeveloperExceptionPage();

            // per https://github.com/open-telemetry/opentelemetry-dotnet/blob/main/src/OpenTelemetry.Exporter.Prometheus/README.md
            app.UseRouting();
            app.UseOpenTelemetryPrometheusScrapingEndpoint();
            app.UseEndpoints(endpoints => { endpoints.MapControllers(); });

            app.UseEndpoints(endpoints =>
            {
                var tracer = endpoints.ServiceProvider.GetService<TracerProvider>().GetTracer("Petabridge.Phobos.Web");
                var actors = endpoints.ServiceProvider.GetService<ActorRegistry>();
                endpoints.MapGet("/", async context =>
                {
                    // fetch actor references from the registry
                    var routerForwarderActor = actors.Get<RouterForwarderActor>();
                    using (var s = tracer.StartActiveSpan("Cluster.Ask"))
                    {
                        // router actor will deliver message randomly to someone in cluster
                        var resp = await routerForwarderActor.Ask<string>($"hit from {context.TraceIdentifier}",
                            TimeSpan.FromSeconds(5));
                        await context.Response.WriteAsync(resp);
                    }
                });
            });
        }
    }

This is the entire configuration using OpenTelemetry, Phobos, and Akka.Hosting.

Installing OpenTelemetry Exporters and Instrumentation

In order to receive any kind of data from our application we need to install the base OpenTelemetry NuGet packages for .NET, including:

With these packages installed, we first create a Resource using the OpenTelemetry SDK:

var resource = ResourceBuilder.CreateDefault()
                .AddService(Assembly.GetEntryAssembly().GetName().Name, serviceInstanceId: $"{Dns.GetHostName()}");

This Resource is going to be what provides all of the service / instanceId / appVersion data to the OpenTelemetry-enabled tracing and metrics services you export your data to - so it's important to spell this out before you start configuring your tracing and metrics export pipelines.

Next, we add some calls to the IServiceCollection to configure our OpenTelemetry TracerProviderBuilder:

// enables OpenTelemetry for ASP.NET / .NET Core
services.AddOpenTelemetryTracing(builder =>
{
    builder
        .SetResourceBuilder(resource)
        .AddPhobosInstrumentation() // extension method provided by Phobos
        .AddSource("Petabridge.Phobos.Web")
        .AddHttpClientInstrumentation(options =>
        {
            // don't trace HTTP output to Seq
            options.Filter = httpRequestMessage => !httpRequestMessage.RequestUri.Host.Contains("seq");
        })
        .AddAspNetCoreInstrumentation(options =>
        {
            options.Filter = context => !context.Request.Path.StartsWithSegments("/metrics");
        })
        .AddJaegerExporter(opt =>
        {
            opt.AgentHost = Environment.GetEnvironmentVariable(JaegerAgentHostEnvironmentVar);
        });
});

The builder.AddPhobosInstrumentation() call causes the TracerProvider, which is configured to export its traces to Phobos, to also include traces that originate from the Phobos library running inside your ActorSystem.

The configuration of the OpenTelemetry MeterProviderBuilder is nearly identical to the tracing configuration:

services.AddOpenTelemetryMetrics(builder =>
{
    builder
        .SetResourceBuilder(ResourceBuilder.CreateDefault()
            .AddService(Assembly.GetEntryAssembly().GetName().Name,
                serviceInstanceId: $"{Dns.GetHostName()}"))
        .AddPhobosInstrumentation()
        .AddHttpClientInstrumentation()
        .AddAspNetCoreInstrumentation()
        .AddPrometheusExporter(opt => { });
});

If you query the /metrics route of your HTTP application you should see a set of Prometheus text format metrics appear once the application has started.

Configuring Phobos and Starting the ActorSystem

Now that we've configured our OpenTelemetry metrics and tracing, the next thing we need to do is configure our ActorSystem to start Phobos!

By default this sample uses Phobos.Hosting, which makes the process of configuring Akka.NET to use Phobos a literal 1-line install:

public static void ConfigureAkka(IServiceCollection services)
{
    services.AddAkka("ClusterSys", (builder, provider) =>
    {
        // use our legacy app.conf file
        var config = ConfigurationFactory.ParseString(File.ReadAllText("app.conf"))
            .BootstrapFromDocker()
            .UseSerilog();

        builder.AddHocon(config)
            .WithClustering(new ClusterOptions { Roles = new[] { "console" } })
            .WithPhobos(AkkaRunMode.AkkaCluster) // enable Phobos
            .StartActors((system, registry) =>
            {
                var consoleActor = system.ActorOf(Props.Create(() => new ConsoleActor()), "console");
                var routerActor = system.ActorOf(Props.Empty.WithRouter(FromConfig.Instance), "echo");
                var routerForwarderActor =
                    system.ActorOf(Props.Create(() => new RouterForwarderActor(routerActor)), "fwd");
                registry.TryRegister<RouterForwarderActor>(routerForwarderActor);
            })
            .StartActors((system, registry) =>
            {
                // start https://cmd.petabridge.com/ for diagnostics and profit
                var pbm = PetabridgeCmd.Get(system); // start Pbm
                pbm.RegisterCommandPalette(ClusterCommands.Instance);
                pbm.RegisterCommandPalette(new RemoteCommands());
                pbm.Start(); // begin listening for PBM management commands
            });
    });
}

Only the .WithPhobos(AkkaRunMode.AkkaCluster) is needed to install Phobos in this scenario.

Tip

If you haven't upgraded to using Akka.Hosting inside your Akka.NET applications, you really should as it's a best practice. However, if you'd prefer to install Phobos without Akka.Hosting you can follow the instructions here: "Configuring Phobos - Classic Phobos Installation."

That's all we need to capture the automatically collected Phobos data, but if we want to manually capture data there's more we can do below.

Calling Phobos APIs

If you want to call the Phobos APIs directly to capture additional data, this is something you can do by calling Context.GetInstrumentation() inside any actor:

public sealed class ConsoleActor : ReceiveActor
{
    private readonly ILoggingAdapter _log = Context.GetLogger(SerilogLogMessageFormatter.Instance);

    public ConsoleActor()
    {
        var processingTimer = Context.GetInstrumentation().Monitor.CreateHistogram<double>("ProcessingTime", "ms");
        Receive<string>(_ =>
        {
            // use the local metrics handle to record a timer duration for how long this block of code takes to execute
            var start = DateTime.UtcNow;

            // start another span programmatically inside actor
            using (var newSpan = Context.GetInstrumentation().Tracer.StartActiveSpan("SecondOp"))
            {
                var child = Context.ActorOf(Props.Create(() => new ChildActor()));
                _log.Info("Spawned {child}", child);

                child.Forward(_);
            }

            var duration = (DateTime.UtcNow - start).TotalMilliseconds;
            processingTimer.Record(duration);
        });
    }
}

When we call Context.GetInstrumentation().Monitor, we are accessing the Meter instance used by the application - and we can create custom metrics, such as a Histogram<double> in this case - and these will all be picked up by Prometheus automatically.

Alternatively, when we call Context.GetInstrumentation().Tracer.StartActiveSpan("SecondOp") - this is creating a new span operation that is a child span of the current one the actor created when it began processing the message, and logs that are recorded inside that using block will automatically be appended to the currently active TelemetrySpan.

Tearing Down the Cluster

When you're done exploring this sample, you can tear down the cluster by running the following command:

PS> ./k8s/destroyAll.cmd

This will delete the phobos-web namespace and all of the resources inside it.

Further Reading

For further reading, please see: