First take on the F# telemetry

vsintegration/src/FSharp.Editor/FSharp.Editor.fsproj

@@ -28,6 +28,7 @@
     </EmbeddedText>
     <Compile Include="$(MSBuildThisFileDirectory)..\..\..\src\LegacyMSBuildResolver\LegacyMSBuildReferenceResolver.fsi" />
     <Compile Include="$(MSBuildThisFileDirectory)..\..\..\src\LegacyMSBuildResolver\LegacyMSBuildReferenceResolver.fs" />
+    <Compile Include="Telemetry\TelemetryReporter.fs" />
     <Compile Include="Common\AssemblyInfo.fs" />
     <Compile Include="Common\Logger.fsi" />
     <Compile Include="Common\Logger.fs" />

vsintegration/src/FSharp.Editor/Hints/Hints.fs

@@ -15,4 +15,9 @@ module Hints =
         Kind: HintKind
         Range: range
         Parts: TaggedText list
-    }
+    }
+
+    let serialize kind =
+        match kind with
+        | TypeHint -> "type"
+        | ParameterNameHint -> "parameterName"

vsintegration/src/FSharp.Editor/Hints/RoslynAdapter.fs

@@ -6,6 +6,7 @@ open System.Collections.Immutable
 open System.ComponentModel.Composition
 open Microsoft.CodeAnalysis.ExternalAccess.FSharp.InlineHints
 open Microsoft.VisualStudio.FSharp.Editor
+open Microsoft.VisualStudio.FSharp.Editor.Telemetry
 
 // So the Roslyn interface is called IFSharpInlineHintsService
 // but our implementation is called just HintsService.
@@ -27,6 +28,9 @@ type internal RoslynAdapter
                 if hintKinds.IsEmpty then
                     return ImmutableArray.Empty
                 else
+                    let hintKindsSerialized = hintKinds |> Set.map Hints.serialize |> String.concat ","
+                    TelemetryReporter.reportEvent "hints" [("hints.kinds", hintKindsSerialized)]
+
                     let! sourceText = document.GetTextAsync cancellationToken |> Async.AwaitTask
                     let! nativeHints =
                         HintService.getHintsForDocument 

vsintegration/src/FSharp.Editor/LanguageService/LanguageService.fs

@@ -27,6 +27,7 @@ open Microsoft.CodeAnalysis.ExternalAccess.FSharp
 open Microsoft.CodeAnalysis.Host
 open Microsoft.CodeAnalysis.Host.Mef
 open Microsoft.VisualStudio.FSharp.Editor.WorkspaceExtensions
+open Microsoft.VisualStudio.FSharp.Editor.Telemetry
 open System.Threading.Tasks
 
 #nowarn "9" // NativePtr.toNativeInt
@@ -104,6 +105,8 @@ type internal FSharpWorkspaceServiceFactory
                 | _ ->
                     let checker =
                         lazy
+                            TelemetryReporter.reportEvent "languageservicestarted" []
+
                             let editorOptions =
                                 let editorOptions = workspace.Services.GetService<EditorOptions>()
 

vsintegration/src/FSharp.Editor/Telemetry/TelemetryReporter.fs

@@ -0,0 +1,28 @@
+// Copyright (c) Microsoft Corporation.  All Rights Reserved.  See License.txt in the project root for license information.
+
+namespace Microsoft.VisualStudio.FSharp.Editor.Telemetry
+
+open Microsoft.VisualStudio.Telemetry
+
+module TelemetryReporter =
+
+    let eventPrefix = "dotnet/fsharp/"
+    let propPrefix = "dotnet.fsharp."
+
+    let getFullEventName name = eventPrefix + name
+    let getFullPropName name = propPrefix + name
+
+    let createEvent name (props: (string * obj) list) = 
+        let event = TelemetryEvent (getFullEventName name)
+
+        props
+        |> List.map (fun (k, v) -> getFullPropName k, v)
+        |> List.iter event.Properties.Add
+
+        event
+
+    let reportEvent name props =
+        let session = TelemetryService.DefaultSession
+        let event = createEvent name props
+        session.PostEvent event
+