(GH-1932) First stab at publishing docs

This may well break, and we won't be able to test this until merged
since it isn't meant to work on PR builds.

build.cake

@@ -7,9 +7,11 @@
 #addin "nuget:?package=Cake.Coverlet&version=2.3.4"
 #addin "nuget:?package=Cake.Docker&version=0.10.1"
 #addin "nuget:?package=Cake.Gem&version=0.8.1"
+#addin "nuget:?package=Cake.Git&version=0.21.0"
 #addin "nuget:?package=Cake.Gitter&version=0.11.1"
 #addin "nuget:?package=Cake.Incubator&version=5.1.0"
 #addin "nuget:?package=Cake.Json&version=4.0.0"
+#addin "nuget:?package=Cake.Kudu&version=0.10.1"
 #addin "nuget:?package=Cake.Npm&version=0.17.0"
 #addin "nuget:?package=Cake.Tfx&version=0.9.1"
 #addin "nuget:?package=Cake.Wyam&version=2.2.9"
@@ -22,6 +24,7 @@
 #tool "nuget:?package=NUnit.ConsoleRunner&version=3.10.0"
 #tool "nuget:?package=nuget.commandline&version=5.2.0"
 #tool "nuget:?package=Wyam&version=2.2.9"
+#tool "nuget:?package=KuduSync.NET&version=1.5.2"
 
 // Install .NET Core Global tools.
 #tool "dotnet:?package=Codecov.Tool&version=1.7.2"
@@ -143,6 +146,7 @@ Task("Publish")
     .IsDependentOn("Publish-NuGet")
     .IsDependentOn("Publish-Chocolatey")
     .IsDependentOn("Publish-Gem")
+    .IsDependentOn("Publish-Documentation")
     .Finally(() =>
 {
     if (publishingError)

build/wyam.cake

@@ -12,7 +12,7 @@ Task("Preview-Documentation")
     {
         Recipe = "Docs",
         Theme = "Samson",
-        OutputPath = MakeAbsolute(MakeAbsolute(Directory("artifacts/Documentation"))),
+        OutputPath = MakeAbsolute(Directory("artifacts/Documentation")),
         RootPath = MakeAbsolute(Directory("docs")),
         Preview = true,
         Watch = true,
@@ -29,3 +29,130 @@ Task("Preview-Documentation")
         }
     });
 });
+
+Task("Force-Publish-Documentation")
+    .IsDependentOn("Clean-Documentation")
+    .WithCriteria(() => DirectoryExists(MakeAbsolute(Directory("docs"))), "Wyam documentation directory is missing")
+    .WithCriteria<BuildParameters>((context, parameters) => !parameters.IsPullRequest, "Publish-Documentation works only for non-PR commits.")
+    .Does<BuildParameters>((parameters) =>
+{
+    Wyam(new WyamSettings
+    {
+        Recipe = "Docs",
+        Theme = "Samson",
+        OutputPath = MakeAbsolute(Directory("artifacts/Documentation")),
+        RootPath = MakeAbsolute(Directory("docs")),
+        ConfigurationFile = MakeAbsolute((FilePath)"config.wyam"),
+        PreviewVirtualDirectory = "GitVersion",
+        Settings = new Dictionary<string, object>
+        {
+            { "Host",  "gittools.github.io" },
+            { "LinkRoot",  "GitVersion" },
+            { "BaseEditUrl", "https://github.com/gittools/GitVersion/tree/master/docs/input/" },
+            { "SourceFiles", MakeAbsolute(parameters.Paths.Directories.Source) + "/**/{!bin,!obj,!packages,!*.Tests,}/**/*.cs" },
+            { "Title", "GitVersion" },
+            { "IncludeGlobalNamespace", false }
+        }
+    });
+
+    PublishDocumentation(parameters);
+});
+
+Task("Publish-Documentation")
+    .IsDependentOn("Clean-Documentation")
+    .WithCriteria(() => DirectoryExists(MakeAbsolute(Directory("docs"))), "Wyam documentation directory is missing")
+    .Does<BuildParameters>((parameters) =>
+{
+    // Check to see if any documentation has changed
+    var sourceCommit = GitLogTip("./");
+    Information("Source Commit Sha: {0}", sourceCommit.Sha);
+    var filesChanged = GitDiff("./", sourceCommit.Sha);
+    Information("Number of changed files: {0}", filesChanged.Count);
+    var docFileChanged = false;
+
+    var wyamDocsFolderDirectoryName = "docs";
+
+    foreach (var file in filesChanged)
+    {
+        var forwardSlash = '/';
+        Verbose("Changed File OldPath: {0}, Path: {1}", file.OldPath, file.Path);
+        if (file.OldPath.Contains(string.Format("{0}{1}", wyamDocsFolderDirectoryName, forwardSlash)) ||
+            file.Path.Contains(string.Format("{0}{1}", wyamDocsFolderDirectoryName, forwardSlash)) ||
+            file.Path.Contains("config.wyam"))
+        {
+        docFileChanged = true;
+        break;
+        }
+    }
+
+    if (docFileChanged)
+    {
+        Information("Detected that documentation files have changed, so running Wyam...");
+
+        Wyam(new WyamSettings
+        {
+            Recipe = "Docs",
+            Theme = "Samson",
+            OutputPath = MakeAbsolute(Directory("artifacts/Documentation")),
+            RootPath = MakeAbsolute(Directory("docs")),
+            ConfigurationFile = MakeAbsolute((FilePath)"config.wyam"),
+            PreviewVirtualDirectory = "GitVersion",
+            Settings = new Dictionary<string, object>
+            {
+                { "Host",  "gittools.github.io" },
+                { "LinkRoot",  "GitVersion" },
+                { "BaseEditUrl", "https://github.com/gittools/GitVersion/tree/master/docs/input/" },
+                { "SourceFiles", MakeAbsolute(parameters.Paths.Directories.Source) + "/**/{!bin,!obj,!packages,!*.Tests,}/**/*.cs" },
+                { "Title", "GitVersion" },
+                { "IncludeGlobalNamespace", false }
+            }
+        });
+
+        PublishDocumentation(parameters);
+    }
+    else
+    {
+        Information("No documentation has changed, so no need to generate documentation");
+    }
+})
+.OnError(exception =>
+{
+    Error(exception.Message);
+    Information("Publish-Documentation Task failed, but continuing with next Task...");
+    publishingError = true;
+});
+
+public void PublishDocumentation(BuildParameters parameters)
+{
+    var sourceCommit = GitLogTip("./");
+
+    var publishFolder = MakeAbsolute(Directory("artifacts/temp/_PublishedDocumentation")).Combine(DateTime.Now.ToString("yyyyMMdd_HHmmss"));
+    Information("Publishing Folder: {0}", publishFolder);
+    Information("Getting publish branch...");
+    GitClone("https://github.com/gittools/GitVersion", publishFolder, new GitCloneSettings{ BranchName = "gh-pages" });
+
+    Information("Sync output files...");
+    Kudu.Sync(MakeAbsolute(Directory("artifacts/Documentation")), publishFolder, new KuduSyncSettings {
+        ArgumentCustomization = args=>args.Append("--ignore").AppendQuoted(".git;CNAME")
+    });
+
+    if (GitHasUncommitedChanges(publishFolder))
+    {
+        Information("Stage all changes...");
+        GitAddAll(publishFolder);
+
+        if (GitHasStagedChanges(publishFolder))
+        {
+            Information("Commit all changes...");
+            GitCommit(
+                publishFolder,
+                sourceCommit.Committer.Name,
+                sourceCommit.Committer.Email,
+                string.Format("Continuous Integration Publish: {0}\r\n{1}", sourceCommit.Sha, sourceCommit.Message)
+            );
+
+            Information("Pushing all changes...");
+            GitPush(publishFolder, parameters.Credentials.GitHub.Token, "x-oauth-basic", "gh-pages");
+        }
+    }
+}