Added command line support for samples project for convenient testing (#54)

* Introducing Stackdriver Exporter for Opencensus C# library

- Current implementation can only store string values
- Added the exporter and trace handler only
- The exporter relies on newest Trace API from Stackdriver.

* Updating translation from ISpan to Stackdriver's Span to cover more fields

* Fixing the issue that prevented Stackdriver API call to succeed:
now construction of Span resource is taken care of by SpanName class that
is part of Stackdriver Trace V2 API.

* - Added support for capturing all types of trace spans (long/bool/string)
- Fixed csproj, so it produces both .NET Core and .NET versions. It also means signing the assembly using the same mechanism as other assemblies in the solution

* - Added support for storing links
- Minor fixes to proto<->opencensus translation methods

* Fixing merge issue

* Added command line support for the Samples project.
This will make it easier to script testing multiple exporters as
well as prevent commenting and uncommenting different test procedures
for different exporters. Finally, it will making test code cleaner for
showing samples embedded in documentation website.

In order to test the exporter, you can either execute it from the command line:
samples.dll prometheus
or to debug using Visual Studio:
Debug => Sample Properties => Debug.
Now create a profile for your testing execution and fill application arguments
if needed.
Now choose your profile in running configuration of Visual Studio.
Running settings are local to the machine and are ignored in PRs.

Author: Simon Zeltser

src/OpenCensus.Collector.AspNetCore/RequestsCollector.cs

@@ -35,7 +35,7 @@ public class RequestsCollector : IDisposable
         /// </summary>
         /// <param name="options">Configuration options for dependencies collector.</param>
         /// <param name="tracer">Tracer to record traced with.</param>
-        /// <param name="sampler">Sampler to use to sample dependnecy calls.</param>
+        /// <param name="sampler">Sampler to use to sample dependency calls.</param>
         /// <param name="propagationComponent">Wire context propagation component.</param>
         public RequestsCollector(RequestsCollectorOptions options, ITracer tracer, ISampler sampler, IPropagationComponent propagationComponent)
         {

src/OpenCensus.Exporter.ApplicationInsights/Implementation/MetricsExporterThread.cs

@@ -97,7 +97,7 @@ internal void Export()
                         metricTelemetry.Properties.Add(name, val);
                     }
 
-                    // Now those propertis needs to be populated.
+                    // Now those properties needs to be populated.
                     //
                     // metricTelemetry.Sum
                     // metricTelemetry.Count

src/OpenCensus.Exporter.Stackdriver/StackdriverExporter.cs

@@ -20,6 +20,9 @@ namespace OpenCensus.Exporter.Stackdriver
     using OpenCensus.Exporter.Stackdriver.Implementation;
     using OpenCensus.Trace.Export;
 
+    /// <summary>
+    /// Implementation of the exporter to Stackdriver
+    /// </summary>
     public class StackdriverExporter
     {
         private const string ExporterName = "StackdriverTraceExporter";
@@ -35,6 +38,9 @@ public StackdriverExporter(string projectId, IExportComponent exportComponent)
             this.exportComponent = exportComponent;
         }
 
+        /// <summary>
+        /// Starts the exporter
+        /// </summary>
         public void Start()
         {
             lock (locker)
@@ -46,11 +52,14 @@ public void Start()
 
                 var traceExporter = new StackdriverTraceExporter(projectId);
                 exportComponent.SpanExporter.RegisterHandler(ExporterName, traceExporter);
-
+                
                 isInitialized = true;
             }
         }
 
+        /// <summary>
+        /// Stops the exporter
+        /// </summary>
         public void Stop()
         {
             lock (locker)

src/Samples/Program.cs

@@ -1,21 +1,61 @@
 namespace Samples
 {
+    using CommandLine;
     using System;
 
+    [Verb("stackdriver", HelpText = "Specify the options required to test Stackdriver exporter", Hidden = false)]
+    class StackdriverOptions
+    {
+        [Option('p', "projectId", HelpText = "Please specify the projectId of your GCP project", Required = true)]
+        public string ProjectId { get; set; }
+    }
+
+    [Verb("zipkin", HelpText = "Specify the options required to test Zipkin exporter")]
+    class ZipkinOptions
+    {
+    }
+
+    [Verb("appInsights", HelpText = "Specify the options required to test ApplicationInsights")]
+    class ApplicationInsightsOptions
+    {
+    }
+
+    [Verb("prometheus", HelpText = "Specify the options required to test Prometheus")]
+    class PrometheusOptions
+    {
+    }
+
+    [Verb("httpclient", HelpText = "Specify the options required to test HttpClient")]
+    class HttpClientOptions
+    {
+    }
+
     /// <summary>
     /// Main samples entry point.
     /// </summary>
     public class Program
     {
         /// <summary>
-        /// Main method.
+        /// Main method - invoke this using command line.
+        /// For example:
+        /// 
+        /// Samples.dll zipkin
+        /// Sample.dll appInsights
+        /// Sample.dll prometheus
         /// </summary>
         /// <param name="args">Arguments from command line.</param>
         public static void Main(string[] args)
         {
-            Console.WriteLine("Uncomment test to run... ");
-
-            TestZipkin.Run();
+            Parser.Default.ParseArguments<ZipkinOptions, ApplicationInsightsOptions, PrometheusOptions, HttpClientOptions, StackdriverOptions>(args)
+                .MapResult(
+                    (ZipkinOptions options) => TestZipkin.Run(),
+                    (ApplicationInsightsOptions options) => TestApplicationInsights.Run(),
+                    (PrometheusOptions options) => TestPrometheus.Run(),
+                    (HttpClientOptions options) => TestHttpClient.Run(),
+                    (StackdriverOptions options) => TestStackdriver.Run(options.ProjectId),
+                    errs => 1);
+                    
+            // TestZipkin.Run();
             // TestApplicationInsights.Run();
             // TestPrometheus.Run();
             // TestHttpClient.Run();

src/Samples/Samples.csproj

@@ -5,6 +5,10 @@
     <TargetFramework>netcoreapp2.0</TargetFramework>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include="CommandLineParser" Version="2.3.0" />
+  </ItemGroup>
+
   <ItemGroup>
     <ProjectReference Include="..\OpenCensus.Collector.Dependencies\OpenCensus.Collector.Dependencies.csproj" />
     <ProjectReference Include="..\OpenCensus.Exporter.Stackdriver\OpenCensus.Exporter.Stackdriver.csproj" />

src/Samples/TestApplicationInsights.cs

@@ -32,7 +32,7 @@ internal class TestApplicationInsights
             Distribution.Create(BucketBoundaries.Create(new List<double>() { 0.0, 16.0 * MiB, 256.0 * MiB })),
             new List<ITagKey>() { FrontendKey });
 
-        internal static void Run()
+        internal static object Run()
         {
             TelemetryConfiguration.Active.InstrumentationKey = "instrumentation-key";
             var exporter = new ApplicationInsightsExporter(Tracing.ExportComponent, Stats.ViewManager, TelemetryConfiguration.Active);
@@ -66,6 +66,8 @@ internal static void Run()
 
             Console.WriteLine("Done... wait for events to arrive to backend!");
             Console.ReadLine();
+
+            return null;
         }
     }
 }

src/Samples/TestHttpClient.cs

@@ -12,7 +12,7 @@ internal class TestHttpClient
     {
         private static ITracer tracer = Tracing.Tracer;
 
-        internal static void Run()
+        internal static object Run()
         {
             Console.WriteLine("Hello World!");
 
@@ -38,6 +38,8 @@ internal static void Run()
             scope.Dispose();
 
             Console.ReadLine();
+
+            return null;
         }
     }
 }

src/Samples/TestPrometheus.cs

@@ -31,7 +31,7 @@ internal class TestPrometheus
             Distribution.Create(BucketBoundaries.Create(new List<double>() { 0.0, 16.0 * MiB, 256.0 * MiB })),
             new List<ITagKey>() { FrontendKey });
 
-        internal static void Run()
+        internal static object Run()
         {
             var exporter = new PrometheusExporter(
                 new PrometheusExporterOptions()
@@ -72,6 +72,8 @@ internal static void Run()
             {
                 exporter.Stop();
             }
+
+            return null;
         }
     }
 }

src/Samples/TestStackdriver.cs

@@ -31,10 +31,9 @@ internal class TestStackdriver
             Distribution.Create(BucketBoundaries.Create(new List<double>() { 0.0, 16.0 * MiB, 256.0 * MiB })),
             new List<ITagKey>() { FrontendKey });
 
-        internal static void Run()
+        internal static object Run(string projectId)
         {
-            Environment.SetEnvironmentVariable("GOOGLE_APPLICATION_CREDENTIALS", @"C:\Users\zeltser\Downloads\aspnetcoreissue-1af8a0ca869b.json");
-            var exporter = new StackdriverExporter("aspnetcoreissue", Tracing.ExportComponent);
+            var exporter = new StackdriverExporter(projectId, Tracing.ExportComponent);
             exporter.Start();
 
             ITagContextBuilder tagContextBuilder = tagger.CurrentBuilder.Put(FrontendKey, TagValue.Create("mobile-ios9.3.5"));
@@ -65,6 +64,8 @@ internal static void Run()
 
             Console.WriteLine("Done... wait for events to arrive to backend!");
             Console.ReadLine();
+
+            return null;
         }
     }
 }

src/Samples/TestZipkin.cs

@@ -10,7 +10,7 @@ internal class TestZipkin
     {
         private static ITracer tracer = Tracing.Tracer;
 
-        internal static void Run()
+        internal static object Run()
         {
             Console.WriteLine("Hello World!");
 
@@ -30,6 +30,8 @@ internal static void Run()
             span2.End();
 
             Console.ReadLine();
+
+            return null;
         }
     }
 }