Updated lab 4 with request tracking

Labs/Assets/Exercise-4-Telemetry/Middleware/ApplicationInsightsMiddleware.cs

@@ -0,0 +1,76 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Threading.Tasks;
+using System.Web;
+using Microsoft.ApplicationInsights;
+using Microsoft.ApplicationInsights.DataContracts;
+using Microsoft.Owin;
+using Owin;
+
+namespace Books.Middleware
+{
+    // Example from http://stackoverflow.com/questions/29471811/how-do-i-enable-application-insights-server-telemetry-on-webapi-project-that-use
+
+    /// <summary>
+    /// Extensions to help adding middleware to the OWIN pipeline
+    /// </summary>
+    public static class OwinExtensions
+    {
+        /// <summary>
+        /// Add Application Insight Request Tracking to the OWIN pipeline
+        /// </summary>
+        /// <param name="app"><see cref="IAppBuilder"/></param>
+        public static void UseApplicationInsights(this IAppBuilder app) => app.Use(typeof(ApplicationInsights));
+
+    }
+
+    /// <summary>
+    /// Allows for tracking requests via Application Insight
+    /// </summary>
+    public class ApplicationInsights : OwinMiddleware
+    {
+
+        /// <summary>
+        /// Allows for tracking requests via Application Insight
+        /// </summary>
+        /// <param name="next"><see cref="OwinMiddleware"/></param>
+        public ApplicationInsights(OwinMiddleware next) : base(next)
+        {
+        }
+
+        /// <summary>
+        /// Tracks the request and sends telemetry to application insights
+        /// </summary>
+        /// <param name="context"><see cref="IOwinContext"/></param>
+        /// <returns></returns>
+        public override async Task Invoke(IOwinContext context)
+        {
+            // Start Time Tracking
+            var sw = new Stopwatch();
+            var startTime = DateTimeOffset.Now;
+            sw.Start();
+
+            await Next.Invoke(context);
+
+            // Send tracking to AI on request completion
+            sw.Stop();
+
+            var request = new RequestTelemetry(
+                name: context.Request.Path.Value,
+                startTime: startTime,
+                duration: sw.Elapsed,
+                responseCode: context.Response.StatusCode.ToString(),
+                success: context.Response.StatusCode >= 200 && context.Response.StatusCode < 300
+                )
+            {
+                Url = context.Request.Uri,
+                HttpMethod = context.Request.Method
+            };
+
+            var client = new TelemetryClient();
+            client.TrackRequest(request);
+        }
+    }
+}

Labs/lab04.md

@@ -10,10 +10,6 @@
 
 ## Create Application Insights
 
-1. **Discussion points:**
-   * Discuss why telemetry and logging are important especially in Microservices architectures
-   * Describe the basics of Application Insights (e.g. high-level features, architecture, pricing models, etc.)
-
 1. Open [Azure Portal](https://portal.azure.com) and sign in.
 
 1. Add *Application Insights* named `PracticalDevOps-Dev` to the resource group `PracticalDevOps-Dev`.<br/>
@@ -40,6 +36,8 @@
     </configuration>
    ```
 
+1. Add the `Microsoft.ApplicationInsights.Web` NuGet package to the Books project
+
 1. Add code setting the instrumentation key to `Startup.cs`:
    ``` 
     public void Configuration(IAppBuilder app)
@@ -67,9 +65,35 @@
         ...
     }
    ```
+
+    ```
+    [HttpPost]
+    [Route("books")]
+    public IHttpActionResult Post(Book newBook)
+    {
+        var telemetryClient = new TelemetryClient();
+        telemetryClient.TrackEvent($"Trying to add a book");
 
-1. **Discussion points:**
-   * Describe basics of Application Insights SDK (e.g. exception logging, metrics)
+        // For demo purposes, return an HTTP 500 error (used to demonstrate logging)
+        return this.InternalServerError();
+    }
+   ```
+
+1. Copy Request tracking middleware implementation from [Assets/Exercise-4-Telemetry](Assets/Exercise-4-Telemetry)  that logs information about all requests to Application Insights.
+
+1. Configure OWIN to use the request tracking middleware by updating `Configuration` method in `Startup.cs`:
+   ``` 
+    public void Configuration(IAppBuilder app)
+    {
+        TelemetryConfiguration.Active.InstrumentationKey = ConfigurationManager.AppSettings["InstrumentationKey"];
+
+        app.UseApplicationInsights();
+
+        // Allow CORS
+        app.UseCors(CorsOptions.AllowAll);
+        ...
+    }
+   ```
 
 
 ## Run Application and View Telemetry
@@ -83,18 +107,9 @@
 
 1. See if your application telemetry appears.
 
-1. **Discussion points:**
-   * Let people play a bit with building Application Insights dashboards in the Azure portal
-   * Describe concept of custom processing of Application Insights data
-   * Brief overview about other Application Insights modules (e.g. for IaaS)
-
 1. Open *Application Insights Search* in Visual Studio while debugging your application. Refresh `http://localhost:2690/api/books` multiple times. See if your application telemetry appears.<br/>
    ![Application Insights Search](img/visual-studio-application-insights.png)
 
- 1. **Discussion points:**
-    * Point out how calls to dependent services are tracked automatically
-    * Show how unnecessary calls to Blob Storage in our app become visible by analyzing Application Insights telemetry data
-
 
 ## Further Ideas