Application Insight TelemetryClient doesn't display logs in Azure Function Console - azure

I implemented TelemetryClient to sink application logs into Application Insight. Below is my implementation
public class Log : ILog
{
private static TelemetryClient telemetryClient = new TelemetryClient() { InstrumentationKey = ConfigurationManager.AppSettings["APPINSIGHTS_INSTRUMENTATIONKEY"] };
public void Error(string message, Exception ex = null)
{
telemetryClient.TrackTrace(message, SeverityLevel.Error);
if (ex != null)
telemetryClient.TrackException(ex);
}
public void Info(string message)
{
telemetryClient.TrackTrace(message, SeverityLevel.Information);
}
public void Verbose(string message)
{
telemetryClient.TrackTrace(message, SeverityLevel.Verbose);
}
public void Warning(string message)
{
telemetryClient.TrackTrace(message, SeverityLevel.Warning);
}
public TelemetryClient TelemetryClient
{
get
{
return telemetryClient;
}
}
}
I could see all custom logs in ApplicationInsight
Problem
When I want to do live monitoring, I could not see custom logs in Azure function logs window, function display below log which I'm not writing.

It's expected. The Azure function logs window you mentioned shows logs written in functions by TraceWriter or ILogger, including those logs created by function runtime, i.e. the function execution results you saw.
Using this Track* method, telemetryClient sends telemetries for display in Diagnostic Search, which are not available in function log streaming.
If you want see those Track* in function logs, output them using TraceWriter or ILogger(recommended) and configure log level in host.json.

Related

Azure Service Bus - Subscribe multiple topics inside the same worker/hosted service

we have a scenario where we must integrate requests with the same destination system, which exposes its operations with REST APIs (provided by a third party, most likely not Azure). So this is a scenario where n messages are mapped in n actions on the same destination system. There is no multicast or broadcast.
So we are considering Service Bus to achieve this, based on previous experiences on other use cases, and taking advantage of dead letter mechanism among other things.
We need to integrate 6 or 7 different actions with the 3rd party. So on Service Bus we can achieve this by creating 1 topic per action, and this is important because the data that travels on the message is different from action to action.
But we are facing a situation when consuming topics. We are able to have an hosted service in Azure (App Service) that listens on a specific topic and does its stuff.
But since we are trying to listen on several topics, we would like to avoid writing and deploying multiple app services, we would like (if possible) to have a single app service where we 'trigger' each ServiceBusProcessor (one per topic) and even though they all rely on the limits of the app service itself, each processor is independent and is listening on its topic in parallel and processing.
I'll share a code sample below of our hosted service, but we found out two options, we would like to have opinions:
Option 1: we send all messages to the same topic, then by using filters we determine which is the appropriate action. This would make code simple, but it would put all messages on the same 'line' which would make the topic an all purpose topic, which seems wrong
Option 2: based on our sample below, which represents a single hosted service which listens on a single topic, we would break it and inject a List of listeners that implement the same interface, and each one of them would be working independently on its topic and its message. We are not sure if this is feasible and if it works properly, because the app service would have to handle multiple ServiceBusProcessors side by side.
We'd like to know if we are missing some option, or if there is any other better way to achieve this. Hope I've explained it well.
I send below a sample of our hosted service. Thanks a lot.
public class MyService : IHostedService, IMyService
{
private ILogger<MyService> _logger;
public MyService(ILogger<MyService> logger)
{
_logger = logger;
}
public Task StartAsync(CancellationToken cancellationToken)
{
ServiceBusClient client = new ServiceBusClient("connectionString");
ServiceBusProcessor processor = client.CreateProcessor("topicName", "subscriptionName");
processor.ProcessMessageAsync += ProcessMessageAsync;
processor.ProcessErrorAsync += ProcessErrorAsync;
_logger.LogInformation("Listener initialized");
return Task.CompletedTask;
}
public Task StopAsync(CancellationToken cancellationToken)
{
return Task.CompletedTask;
}
public async Task ProcessMessageAsync(ProcessMessageEventArgs args)
{
var body = args.Message.Body;
// Do stuff with this body...
await args.CompleteMessageAsync(args.Message);
}
public Task ProcessErrorAsync(ProcessErrorEventArgs args)
{
_logger.LogError($"Error ocurred: {args.Exception.ToString()} with message: {args.Exception.Message}");
return Task.CompletedTask;
}
}
Then at ConfigureServices:
services.AddHostedService<MyService>();
So, following option 2, the sample above would be transformed in the following, considering 2 listeners:
public interface IMyService
{
}
public interface IMyListener
{
Task Initialize();
Task ProcessMessageAsync(ProcessMessageEventArgs args);
Task ProcessErrorAsync(ProcessErrorEventArgs args);
}
public class BaseListener
{
private string _connectionString;
private string _topicName;
private string _subscriptionName;
private ILogger<BaseListener> _logger;
public BaseListener(ILogger<BaseListener> logger, string connectionString, string topicName, string subscriptionName)
{
this._connectionString = connectionString;
this._topicName = topicName;
this._subscriptionName = subscriptionName;
this._logger = logger;
}
public Task Initialize()
{
ServiceBusClient client = new ServiceBusClient(this._connectionString);
ServiceBusProcessor processor = client.CreateProcessor(this._topicName, this._subscriptionName);
processor.ProcessMessageAsync += ProcessMessageAsync;
processor.ProcessErrorAsync += ProcessErrorAsync;
_logger.LogInformation("Listener initialized");
return Task.CompletedTask;
}
public async Task ProcessMessageAsync(ProcessMessageEventArgs args)
{
var body = args.Message.Body;
// Do stuff with this body...
await args.CompleteMessageAsync(args.Message);
}
public Task ProcessErrorAsync(ProcessErrorEventArgs args)
{
return Task.CompletedTask;
}
}
public class MyListener1: BaseListener, IMyListener
{
public MyListener1(ILogger<MyListener1> logger) : base(logger, "connectionString", "topic1", "subscription")
{
}
}
public class MyListener2 : BaseListener, IMyListener
{
public MyListener2(ILogger<MyListener2> logger) : base(logger, "connectionString", "topic2", "subscription")
{
}
}
public class MyService : IHostedService, IMyService
{
private ILogger<MyService> _logger;
private IEnumerable<IMyListener> _listeners;
public MyService(ILogger<MyService> logger, IEnumerable<IMyListener> listeners)
{
_logger = logger;
_listeners = listeners;
}
public Task StartAsync(CancellationToken cancellationToken)
{
foreach(var listener in this._listeners)
{
listener.Initialize();
}
_logger.LogInformation("Listeners initialized");
return Task.CompletedTask;
}
public Task StopAsync(CancellationToken cancellationToken)
{
return Task.CompletedTask;
}
}
And on ConfigureServices:
services.AddHostedService<MyService>();
services.AddSingleton<IMyListener, MyListener1>();
services.AddSingleton<IMyListener, MyListener2>();

Application Insights with multiple applications

I have an Application Insights which logs traces from an App Service and an App Function (one resource for 2 functions).
I need to filter traces according to the resource (App Service or App Function) and, if possible, for the App Function which function is actually logging.
Looking at the traces I see the following list of properties:
I thought to find the resource name in the appName property, instead there is the Application Insights resource name, which is useless for me, since all those traces are from that resource.
Note: I don't like the workaround to set a prefix in the message to filter the traces.
UPDATE
I followed Peter Bons suggestions and I created a brand new Function V3 project. The basic version of the project worked also without the Telemetry Initializer, I mean that the Cloud_RoleName property was correctly populated.
Then, I added my changes to adapt the sample code and I found that the problem comes up when I inject a new Telemetry Client. I know, it is not recommended to manually inject TelemetryClient in App Function, but I absolutely need to send Custom Event to Application Insights and, as far as I know, it is not possible with ILogger interface used by default in App Function.
Startup.cs
public class Startup : FunctionsStartup
{
private TelemetryConfiguration telemetryConfiguration;
public override void Configure(IFunctionsHostBuilder builder)
{
var localRoot = Environment.GetEnvironmentVariable("AzureWebJobsScriptRoot");
var azureRoot = $"{Environment.GetEnvironmentVariable("HOME")}/site/wwwroot";
var configBuilder = new ConfigurationBuilder()
.SetBasePath(localRoot ?? azureRoot)
.AddEnvironmentVariables()
.AddJsonFile("local.settings.json", optional: true, reloadOnChange: true);
var configuration = configBuilder.Build();
if (builder != null)
{
this.ConfigureServices(builder.Services, configuration);
}
}
private void ConfigureServices(IServiceCollection services, IConfiguration configuration)
{
services.AddSingleton<ITelemetryInitializer>(x => new CustomTelemetryInitializer(configuration["appFunctionName"]));
telemetryConfiguration = new TelemetryConfiguration(configuration["APPINSIGHTS_INSTRUMENTATIONKEY"]);
telemetryConfiguration.TelemetryInitializers.Add(new OperationCorrelationTelemetryInitializer());
var telemetryClient = new TelemetryClient(telemetryConfiguration);
services.AddSingleton(telemetryClient);
services.AddSingleton<ISampleInterface, SampleService>();
}
}
CustomTelemetryInitializer.cs
public class CustomTelemetryInitializer : ITelemetryInitializer
{
private readonly string roleName;
public CustomTelemetryInitializer(string roleName)
{
this.roleName = roleName;
}
public void Initialize(ITelemetry telemetry)
{
if (string.IsNullOrEmpty(telemetry?.Context?.Cloud?.RoleName))
{
telemetry.Context.Cloud.RoleName = roleName;
}
}
}
SampleService.cs
public class SampleService : ISampleInterface
{
private TelemetryClient telemetryClient;
public SampleService(TelemetryClient telemetryClient)
{
this.telemetryClient = telemetryClient;
}
public void TestAppInsights()
{
telemetryClient.TrackEvent("Sample Custom Event with init");
telemetryClient.TrackTrace("Sample Custom Trace with init");
}
}
Function.cs
public class Function1
{
private ISampleInterface service;
public Function1(ISampleInterface service)
{
this.service = service;
}
[FunctionName("Function1")]
public async Task<IActionResult> Run(
[HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)] HttpRequest req,
ILogger log)
{
log.LogInformation("C# HTTP trigger function processed a request with init.");
this.service.TestAppInsights();
string name = req.Query["name"];
string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
dynamic data = JsonConvert.DeserializeObject(requestBody);
name = name ?? data?.name;
string responseMessage = string.IsNullOrEmpty(name)
? "This HTTP triggered function executed successfully. Pass a name in the query string or in the request body for a personalized response."
: $"Hello, {name}. This HTTP triggered function executed successfully.";
return new OkObjectResult(responseMessage);
}
}
How about inspecting the cloud_RoleName property, available to all telemetry? By default it will have the name of the webapp or function (including slot names) as the value.
Otherwise, if you want to add custom properties or modify properties for all telemetry at one place you can make use of a telemetry initializer as demonstrated here:
using Microsoft.ApplicationInsights.Channel;
using Microsoft.ApplicationInsights.Extensibility;
namespace CustomInitializer.Telemetry
{
public class MyTelemetryInitializer : ITelemetryInitializer
{
public void Initialize(ITelemetry telemetry)
{
telemetry.Context.Cloud.RoleName = "HttpTriggered";
}
}
}
This avoids having to prefix all traces as you mentioned as a work around by having a single piece of code all telemetry passes through:
Another thing
[...] but I absolutely need to send Custom Event to Application Insights and, as far as I know, it is not possible with ILogger interface used by default in App Function.
Do note that you can redirect the output emitted by using the ILogger interface to Application Insights. It will show up as a trace.

How do I find application insights logs for specific ILogger<T>

I use asp.net core logging like this:
public class MyClass
{
private readonly ILogger<MyClass> _logger;
public readonly EventId NoEntryFoundEventId = new EventId(1, "No Entry Found");
public MyClass(ILogger<MyClass> logger)
{
_logger = logger;
}
public void Foo(decimal entryId)
{
_logger.LogError(NoEntryFoundEventId, "MyCustomMessage\t: Entry ID: {EntryId}", entryId);
}
}
An I setup the logger like this:
services.AddApplicationInsightsTelemetry();
loggerFactory.AddApplicationInsights(app.ApplicationServices, LogLevel.Information)
How do I find the logs for MyClass in Azure portal?
As far as I understand, you want to find the log entries in Application Insights that are specifically linked to your class MyClass.
It is in the Property "CategoryName".
Getting Started with Application Insights for ASP.NET Core
Your program.cs should look something like this
public static IWebHost BuildWebHost(string[] args) =>
WebHost.CreateDefaultBuilder(args)
.UseStartup<Startup>()
.UseApplicationInsights()
.Build();
Then link the ASP.NET ILogger to Application Insights
public void Configure(IApplicationBuilder app, IHostingEnvironment env,
ILoggerFactory loggerFactory)
{
/*...existing code..*/
loggerFactory.AddApplicationInsights(app.ApplicationServices, LogLevel.Warning);
}
If you set it up like this, your ILogger will automatically use the full name of MyClass as a category name, and you will see that in Application Insights under the property "CategoryName".
https://github.com/Microsoft/ApplicationInsights-aspnetcore/tree/develop/src/Microsoft.ApplicationInsights.AspNetCore/Logging/Implementation
private void PopulateTelemetry(ITelemetry telemetry,
IReadOnlyList<KeyValuePair<string, object>> stateDictionary, EventId eventId)
{
IDictionary<string, string> dict = telemetry.Context.Properties;
dict["CategoryName"] = this.categoryName;
...
See also this question for an image on how this will look in Application Insights:
Using Application Insights with ILoggerFactory
(Image is taken directly from this answer, please tell me if this is not allowed and I will remove it)
The data is added as a "custom property" and can be filtered like that in the portal:
Some more info:
https://learn.microsoft.com/en-us/azure/application-insights/app-insights-api-custom-events-metrics#properties
https://learn.microsoft.com/en-us/azure/application-insights/app-insights-analytics-tour#custom-properties-and-measurements

How to use/enable EventHubsEventSource traces for EventHubClient in Azure servicebus

In the source code of EventHubClient (from Azure SDK) (LINK) I see that there are diagnostic traces in part of the function calls. I want to find out how I can enable this so that the traces show up somewhere.
I want to find out how I can enable this so that the traces show up somewhere.
You need to implement a EventListener to save the logs to anywhere you want. Following is a sample of writing logs to a file.
public sealed class FileEventListener : EventListener
{
private string _filePath;
public FileEventListener(string name)
{
this._filePath = name;
}
private void WriteToFile(string message)
{
File.AppendAllText(_filePath, DateTime.Now.ToString() + message + "\n");
}
protected override void OnEventWritten(EventWrittenEventArgs eventData)
{
WriteToFile(string.Format(eventData.Message, eventData.Payload.ToArray()));
}
protected override void OnEventSourceCreated(EventSource eventSource)
{
}
}
After implemented your own EventListener, you could use it in your application.
EventListener myFileListener = new FileEventListener("D:\\log.txt");
myFileListener.EnableEvents(EventHubsEventSource.Log, EventLevel.LogAlways);

Azure Webjobs and Queues

I am working with an Azure Service Bus Queue (or potentially a topic if required), and would like to know how a Web Job can be used with the Queue.
When a message comes onto the queue it represents a process that will run within the web job (or be started from the webjob). This process might be quick, 30 seconds, or it might be slow, 1 hour etc.
Can I use a single Web Job for this and somehow say that it should be running no more than 10 of these processes at a time?
Yes you can use a WebJob. I have created a simple WebJob with Storage Queue to just guide how it can be done. The below workflow will run only ten process at a time and keep all the other requests in memory of ConcurrentQueue. You will have to implement the logic to dequeue it and consume it
public class Functions
{
public delegate void CompletedProcessHandler(object sender, CompletedProcessHandlerArgs args);
static readonly Dictionary<int, CustomProcess> _dictionary =
new Dictionary<int, CustomProcess>();
static readonly ConcurrentQueue<ProcessEntity> _remaining =
new ConcurrentQueue<ProcessEntity>();
// This function will get triggered/executed when a new message is written
// on an Azure Queue called queue.
public static void ProcessQueueMessage([QueueTrigger("testqueue")] ProcessEntity msg,
TextWriter log)
{
if (_dictionary.Count <= 10)
{
var newProcess = new CustomProcess((_dictionary.Last().Key) + 1,
msg.Duration);
}
else
{
_remaining.Enqueue(msg);
}
}
public static void CompletedProcess(object sender, CompletedProcessHandlerArgs args)
{
_dictionary[Int32.Parse(args.ProcessID)].Dispose();
_dictionary.Remove(Int32.Parse(args.ProcessID));
}
}
public class CustomProcess : IDisposable
{
public event Functions.CompletedProcessHandler OnProcessCompleted;
private CancellationTokenSource _token;
private string _id;
private Timer _timer;
public CustomProcess(int i, int duration)
{
_timer = new Timer { Enabled = true, Interval = duration * 1000 };
_timer.Elapsed += Timer_Elapsed;
_id = i.ToString();
_token = new CancellationTokenSource();
Task.Factory.StartNew(() => WriteMessages());
_timer.Start();
OnProcessCompleted += Functions.CompletedProcess;
}
private void Timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
_token.Cancel();
OnProcessCompleted?.Invoke(this, new CompletedProcessHandlerArgs(_id));
}
private void WriteMessages()
{
while (!_token.Token.IsCancellationRequested)
{
Console.WriteLine("Test Message from process " + _id);
}
}
public void Dispose()
{
_token.Dispose();
_timer.Dispose();
}
}
public class CompletedProcessHandlerArgs : EventArgs
{
public string ProcessID { get; set; }
public CompletedProcessHandlerArgs(string ID)
{
ProcessID = ID;
}
}
public class ProcessEntity
{
public int Duration { get; set; }
}
In the app.config of the web job you need to provide the two app settings
<add name="AzureWebJobsDashboard"
connectionString="DefaultEndpointsProtocol=https;AccountName=[AccountName];AccountKey=[AccountKey]" />
<add name="AzureWebJobsStorage"
connectionString="DefaultEndpointsProtocol=https;AccountName=[AccountName];AccountKey=[AccountKey]" />
The Program file is the default one from the Visual Studio template
public class Program
{
// Please set the following connection strings in app.config for this WebJob to run:
// AzureWebJobsDashboard and AzureWebJobsStorage
static void Main()
{
var host = new JobHost();
// The following code ensures that the WebJob will be running continuously
host.RunAndBlock();
}
}
WebJob will keep dequeue the message the moment it comes. Since you want only 10 to run at a time you will have to enqueue the message in memory and wait for running process to complete before you start a new one
As #Rick has mentioned you can set the is_Singleton property to true in settings.job file of the web job
Yes, you can trigger a web job with an Azure Service Bus Queue or Topic. A good example to look at to get you going would be the Service Bus quick start project template in Visual Studio.
In particular, you want to look at the ServiceBusTrigger attribute that the Web Jobs SDK provides.
As for the scalability of the web job, this will scale according to your web app instances. So, if you had say 5 instances of your web app with always on enabled, then you would have 5 instances of your web job. As an additional comment on this, if you wanted just one instance of the web job in an environment of 5 web app instances, then you could set the is_singleton property to true in the settings.job file.

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