Generate release notes (#3201)

This commit adds the generation of draft release notes to build/output.

Closed issues for labelled with the target release label are fetched from
Github and grouped by Bug,Feature and Deprecation labels, appearing in
more than one group if featuring more than one of those labels.

Comparison link is generated from the version in global.json and the
version being released.
(cherry picked from commit 238e890)

(cherry picked from commit ed82eb8)

Author: russcam

build/scripts/Paths.fsx

@@ -15,7 +15,9 @@ open Projects
 
 module Paths =
 
-    let Repository = "https://github.com/elastic/elasticsearch-net"
+    let OwnerName = "elastic"
+    let RepositoryName = "elasticsearch-net"
+    let Repository = sprintf "https://github.com/%s/%s" OwnerName RepositoryName
 
     let BuildFolder = "build"
     let BuildOutput = sprintf "%s/output" BuildFolder

build/scripts/Releasing.fsx

@@ -1,19 +1,24 @@
 #I @"../../packages/build/FAKE/tools"
+#I @"../../packages/build/Octokit/lib/net45"
 #r @"FakeLib.dll"
+#r "Octokit.dll"
+#nowarn "0044" //TODO sort out FAKE 5
 
 #load @"Projects.fsx"
 #load @"Paths.fsx"
 #load @"Tooling.fsx"
 #load @"Versioning.fsx"
 
 open System
+open System.Collections.Generic
 open System.IO
 open System.Linq
 open System.Text
 open System.Xml.Linq
 open Microsoft.FSharp.Quotations
 open Microsoft.FSharp.Quotations.Patterns
 open Fake
+open Octokit
 
 open Paths
 open Projects
@@ -90,3 +95,56 @@ module Release =
             | 0 -> traceFAKE "publish to myget succeeded" |> ignore
             | _ -> failwith "publish to myget failed" |> ignore
         )
+        
+    let GenerateNotes() = 
+        let previousVersion = Versioning.GlobalJsonVersion.ToString()
+        let currentVersion = Versioning.CurrentVersion.ToString()
+        let label = sprintf "v%s" currentVersion
+        let releaseNotes = sprintf "ReleaseNotes-%s.md" currentVersion |> Paths.Output      
+        let client = new GitHubClient(new ProductHeaderValue("ReleaseNotesGenerator"))
+        client.Credentials <- Credentials.Anonymous
+              
+        let filter = new RepositoryIssueRequest()
+        filter.Labels.Add label
+        filter.State <- ItemStateFilter.Closed
+        
+        let labelHeaders =
+           [("Feature", "Features & Enhancements");
+            ("Bug", "Bug Fixes");
+            ("Deprecation", "Deprecations");]
+           |> Map.ofList
+           
+        let groupByLabel (issues:IReadOnlyList<Issue>) =
+            let dict = new Dictionary<string, Issue list>()         
+            for issue in issues do
+                for labelHeader in labelHeaders do
+                    if issue.Labels.Any(fun l -> l.Name = labelHeader.Key) then
+                        let exists,list = dict.TryGetValue(labelHeader.Key)
+                        match exists with 
+                        | true -> dict.[labelHeader.Key] <- issue :: list
+                        | false -> dict.Add(labelHeader.Key, [issue])
+            dict
+        
+        let closedIssues = client.Issue.GetAllForRepository(Paths.OwnerName, Paths.RepositoryName, filter)
+                           |> Async.AwaitTask
+                           |> Async.RunSynchronously
+                           |> groupByLabel
+                              
+        use file = File.OpenWrite <| releaseNotes
+        use writer = new StreamWriter(file)                   
+        writer.WriteLine(sprintf "%s/compare/%s...%s" Paths.Repository previousVersion currentVersion)
+        writer.WriteLine()
+        for closedIssue in closedIssues do
+            labelHeaders.[closedIssue.Key] |> sprintf "## %s" |> writer.WriteLine    
+            writer.WriteLine()
+            for issue in closedIssue.Value do
+                sprintf "- #%i %s" issue.Number issue.Title |> writer.WriteLine
+            writer.WriteLine()
+              
+        sprintf "### [View the full list of issues and PRs](%s/issues?utf8=%%E2%%9C%%93&q=label%%3A%s)" Paths.Repository label
+        |> writer.WriteLine
+        
+                           
+                      
+        
+        

build/scripts/Targets.fsx

@@ -70,6 +70,7 @@ Target "Release" <| fun _ ->
     Release.NugetPack()   
     Versioning.ValidateArtifacts()
     StrongName.ValidateDllsInNugetPackage()
+    Release.GenerateNotes()
 
 Target "Canary" <| fun _ -> 
     trace "Running canary build" 

build/scripts/Versioning.fsx

@@ -38,9 +38,11 @@ module Versioning =
         newGlobalJson.JsonValue.WriteTo(tw, JsonSaveOptions.None)
         tracefn "Written (%s) to global.json as the current version will use this version from now on as current in the build" (version.ToString()) 
 
+    let GlobalJsonVersion = parse(globalJson.Version)
+
     let CurrentVersion =
         Commandline.parse()
-        let currentVersion = parse(globalJson.Version)
+        let currentVersion = GlobalJsonVersion
         let bv = getBuildParam "version"
         let buildVersion = if (isNullOrEmpty bv) then None else Some(parse(bv)) 
         match (getBuildParam "target", buildVersion) with

paket.dependencies

@@ -7,5 +7,7 @@ group build
     nuget FAKE
     nuget FSharp.Data
 
-    #Profiling.fsx uses this
+    # persisting profiling results
     nuget Nest framework: net45
+	
+	nuget Octokit