create and link forum topic for each blog post

app/controllers/Blog.scala

@@ -44,6 +44,31 @@ object Blog extends LilaController {
     }
   }
 
+  def discuss(id: String) = Open { implicit ctx =>
+    val categSlug = "general-chess-discussion"
+    val topicSlug = s"blog-$id"
+    val redirect = Redirect(routes.ForumTopic.show(categSlug, topicSlug))
+    lila.forum.TopicRepo.existsByTree(categSlug, id) flatMap {
+      case true => fuccess(redirect)
+      case _ => blogApi context none flatMap { implicit prismic =>
+        blogApi.one(prismic.api, none, id) flatMap {
+          _ ?? { doc =>
+            lila.forum.CategRepo.bySlug(categSlug) flatMap {
+              _ ?? { categ =>
+                Env.forum.topicApi.makeBlogDiscuss(
+                  categ = categ,
+                  slug = topicSlug,
+                  name = doc.getText("blog.title") | "New blog post",
+                  url = s"${Env.api.Net.BaseUrl}${routes.Blog.show(doc.id, doc.slug)}"
+                )
+              }
+            } inject redirect
+          }
+        }
+      }
+    }
+  }
+
   // -- Helper: Check if the slug is valid and redirect to the most recent version id needed
   private def checkSlug(document: Option[Document], slug: String)(callback: Either[String, Document] => Result)(implicit ctx: lila.api.Context) =
     document.collect {

app/views/blog/show.scala.html

@@ -29,5 +29,14 @@ description = ~doc.getText("blog.shortlede")).some) {
   <div class="body embed_analyse">
     @doc.getHtml("blog.body", prismic.linkResolver).map(lila.blog.Youtube.fixStartTimes).map(lila.blog.ProtocolFix.remove).map(Html.apply)
   </div>
+  @NotForKids {
+  <div class="footer">
+    @if(prismic.maybeRef.isEmpty) {
+    <a href="@routes.Blog.discuss(doc.id)" class="button text discuss" data-icon="d">Discuss this blog post in the forum</a>
+    } else {
+    <p>This is a preview.</p>
+    }
+  </div>
+  }
 </div>
 }

conf/routes

@@ -74,6 +74,7 @@ GET   /socket                          controllers.Main.websocket
 
 # Blog
 GET   /blog                            controllers.Blog.index(ref: Option[String] ?= None)
+GET   /blog/discuss/:id                controllers.Blog.discuss(id: String)
 GET   /blog/:id/:slug                  controllers.Blog.show(id: String, slug: String, ref: Option[String] ?= None)
 GET   /blog.atom                       controllers.Blog.atom(ref: Option[String] ?= None)
 

modules/forum/src/main/TopicApi.scala

@@ -87,6 +87,35 @@ private[forum] final class TopicApi(
           } inject topic
     }
 
+  def makeBlogDiscuss(categ: Categ, slug: String, name: String, url: String): Funit = {
+    val topic = Topic.make(
+      categId = categ.slug,
+      slug = slug,
+      name = name,
+      troll = false,
+      hidden = false
+    )
+    val post = Post.make(
+      topicId = topic.id,
+      author = none,
+      userId = "lichess".some,
+      ip = none,
+      troll = false,
+      hidden = false,
+      text = s"Comments on $url",
+      lang = none,
+      number = 1,
+      categId = categ.id,
+      modIcon = true.some
+    )
+    env.postColl.insert(post) >>
+      env.topicColl.insert(topic withPost post) >>
+      env.categColl.update($id(categ.id), categ withTopic post) >>-
+      (indexer ! InsertPost(post)) >>-
+      env.recent.invalidate >>-
+      bus.publish(actorApi.CreatePost(post, topic), 'forumPost) void
+  }
+
   def paginator(categ: Categ, page: Int, troll: Boolean): Fu[Paginator[TopicView]] = {
     val adapter = new Adapter[Topic](
       collection = env.topicColl,

modules/forum/src/main/TopicRepo.scala

@@ -38,6 +38,9 @@ sealed abstract class TopicRepo(troll: Boolean) {
   def byTree(categSlug: String, slug: String): Fu[Option[Topic]] =
     coll.uno[Topic]($doc("categId" -> categSlug, "slug" -> slug) ++ trollFilter)
 
+  def existsByTree(categSlug: String, slug: String): Fu[Boolean] =
+    coll.exists($doc("categId" -> categSlug, "slug" -> slug))
+
   def stickyByCateg(categ: Categ): Fu[List[Topic]] =
     coll.list[Topic](byCategQuery(categ) ++ stickyQuery)
 

public/stylesheets/blog.css

@@ -41,7 +41,7 @@
 #lichess_blog .body {
   font-size: 1.4em;
   line-height: 1.6;
-  margin: 20px 0 80px 0;
+  margin: 20px 0 60px 0;
   cursor: initial;
 }
 #lichess_blog .body p {
@@ -103,3 +103,8 @@
 #lichess_blog .list .more {
   text-align: center;
 }
+#lichess_blog .footer {
+  text-align: center;
+  font-size: 1.3em;
+  margin-bottom: 40px;
+}