feat(post-qa): only allows one best solution

Author: mydearxym

lib/groupher_server/cms/article_comment.ex

@@ -17,8 +17,8 @@ defmodule GroupherServer.CMS.ArticleComment do
   @article_threads get_config(:article, :threads)
 
   @required_fields ~w(body_html author_id)a
-  @optional_fields ~w(reply_to_id replies_count is_folded is_deleted floor is_article_author thread is_for_question)a
-  @updatable_fields ~w(is_folded is_deleted floor upvotes_count is_pinned is_for_question)a
+  @optional_fields ~w(reply_to_id replies_count is_folded is_deleted floor is_article_author thread is_for_question is_solution)a
+  @updatable_fields ~w(is_folded is_deleted floor upvotes_count is_pinned is_for_question is_solution)a
 
   @article_fields @article_threads |> Enum.map(&:"#{&1}_id")
 
@@ -58,7 +58,9 @@ defmodule GroupherServer.CMS.ArticleComment do
     field(:is_deleted, :boolean, default: false)
     # 楼层
     field(:floor, :integer, default: 0)
+
     field(:is_for_question, :boolean, default: false)
+    field(:is_solution, :boolean, default: false)
 
     # 是否是评论文章的作者
     field(:is_article_author, :boolean, default: false)

lib/groupher_server/cms/delegates/article_comment.ex

@@ -140,22 +140,27 @@ defmodule GroupherServer.CMS.Delegate.ArticleComment do
   end
 
   def mark_comment_solution(article_comment_id, user) do
-    do_mark_comment_solution(article_comment_id, user, true)
+    with {:ok, article_comment} <- ORM.find(ArticleComment, article_comment_id),
+         {:ok, post} <- ORM.find(CMS.Post, article_comment.post_id, preload: [author: :user]) do
+      # 确保只有一个最佳答案
+      batch_update_solution_flag(post, false)
+      do_mark_comment_solution(post, article_comment, user, true)
+    end
   end
 
   def undo_mark_comment_solution(article_comment_id, user) do
-    do_mark_comment_solution(article_comment_id, user, false)
+    with {:ok, article_comment} <- ORM.find(ArticleComment, article_comment_id),
+         {:ok, post} <- ORM.find(CMS.Post, article_comment.post_id, preload: [author: :user]) do
+      do_mark_comment_solution(post, article_comment, user, false)
+    end
   end
 
-  defp do_mark_comment_solution(article_comment_id, user, is_solution) do
-    with {:ok, article_comment} <- ORM.find(ArticleComment, article_comment_id),
-         {:ok, post} <- ORM.find(CMS.Post, article_comment.post_id, preload: [author: :user]),
-         # check if user is questioner
-         true <- user.id == post.author.user.id do
+  defp do_mark_comment_solution(post, %ArticleComment{} = article_comment, user, is_solution) do
+    # check if user is questioner
+    with true <- user.id == post.author.user.id do
       Multi.new()
       |> Multi.run(:mark_solution, fn _, _ ->
-        meta = article_comment.meta |> Map.merge(%{is_solution: is_solution})
-        ORM.update_meta(article_comment, meta)
+        ORM.update(article_comment, %{is_solution: is_solution})
       end)
       |> Multi.run(:update_post_state, fn _, _ ->
         ORM.update(post, %{is_solved: is_solution, solution_digest: article_comment.body_html})
@@ -348,6 +353,17 @@ defmodule GroupherServer.CMS.Delegate.ArticleComment do
 
   defp set_question_flag_ifneed(_, comment), do: ORM.update(comment, %{is_for_question: false})
 
+  # batch update is_solution flag for artilce comment
+  defp batch_update_solution_flag(%CMS.Post{} = post, is_question) do
+    from(c in ArticleComment,
+      where: c.post_id == ^post.id,
+      update: [set: [is_solution: ^is_question]]
+    )
+    |> Repo.update_all([])
+
+    {:ok, :pass}
+  end
+
   defp result({:ok, %{set_question_flag_ifneed: result}}), do: {:ok, result}
   defp result({:ok, %{delete_article_comment: result}}), do: {:ok, result}
   defp result({:ok, %{mark_solution: result}}), do: {:ok, result}

lib/groupher_server/cms/embeds/article_comment_meta.ex

@@ -7,7 +7,7 @@ defmodule GroupherServer.CMS.Embeds.ArticleCommentMeta do
 
   import Ecto.Changeset
 
-  @optional_fields ~w(is_article_author_upvoted report_count is_reply_to_others reported_count reported_user_ids is_solution)a
+  @optional_fields ~w(is_article_author_upvoted report_count is_reply_to_others reported_count reported_user_ids)a
 
   @doc "for test usage"
   def default_meta() do
@@ -17,8 +17,7 @@ defmodule GroupherServer.CMS.Embeds.ArticleCommentMeta do
       report_count: 0,
       upvoted_user_ids: [],
       reported_user_ids: [],
-      reported_count: 0,
-      is_solution: false
+      reported_count: 0
     }
   end
 
@@ -32,8 +31,6 @@ defmodule GroupherServer.CMS.Embeds.ArticleCommentMeta do
     field(:upvoted_user_ids, {:array, :integer}, default: [])
     field(:reported_user_ids, {:array, :integer}, default: [])
     field(:reported_count, :integer, default: 0)
-
-    field(:is_solution, :boolean, default: false)
   end
 
   def changeset(struct, params) do

lib/helper/error_code.ex

@@ -51,6 +51,7 @@ defmodule Helper.ErrorCode do
   def ecode(:undo_sink_old_article), do: @article_base + 7
   def ecode(:article_comment_locked), do: @article_base + 8
   def ecode(:require_questioner), do: @article_base + 9
+  # def ecode(:already_solved), do: @article_base + 10
 
   def ecode, do: @default_base
   # def ecode(_), do: @default_base

priv/repo/migrations/20210602144450_add_solution_digest_to_comment.exs

@@ -0,0 +1,9 @@
+defmodule GroupherServer.Repo.Migrations.AddSolutionDigestToComment do
+  use Ecto.Migration
+
+  def change do
+    alter table(:articles_comments) do
+      add(:is_solution, :boolean, default: false)
+    end
+  end
+end

test/groupher_server/cms/comments/post_comment_test.exs

@@ -5,7 +5,7 @@ defmodule GroupherServer.Test.CMS.Comments.PostComment do
   import Helper.Utils, only: [get_config: 2]
 
   alias Helper.ORM
-  alias GroupherServer.{Accounts, CMS}
+  alias GroupherServer.{Accounts, CMS, Repo}
 
   alias CMS.{ArticleComment, ArticlePinnedComment, Embeds, Post}
 
@@ -677,7 +677,7 @@ defmodule GroupherServer.Test.CMS.Comments.PostComment do
       {:ok, post_comment} = CMS.create_article_comment(:post, post.id, "comment", user)
 
       assert not post_comment.is_for_question
-      assert not post_comment.meta.is_solution
+      assert not post_comment.is_solution
     end
 
     @tag :wip2
@@ -725,7 +725,7 @@ defmodule GroupherServer.Test.CMS.Comments.PostComment do
       {:ok, comment} = CMS.create_article_comment(:post, post.id, "comment", post_author)
       {:ok, comment} = CMS.mark_comment_solution(comment.id, post_author)
 
-      assert comment.meta.is_solution
+      assert comment.is_solution
 
       {:ok, post} = ORM.find(Post, post.id)
       assert post.is_solved
@@ -759,7 +759,7 @@ defmodule GroupherServer.Test.CMS.Comments.PostComment do
 
       {:ok, comment} = CMS.undo_mark_comment_solution(comment.id, post_author)
 
-      assert not comment.meta.is_solution
+      assert not comment.is_solution
 
       {:ok, post} = ORM.find(Post, post.id)
       assert not post.is_solved
@@ -779,5 +779,27 @@ defmodule GroupherServer.Test.CMS.Comments.PostComment do
 
       reason |> is_error?(:require_questioner)
     end
+
+    @tag :wip
+    test "can only mark one best comment as solution", ~m(user community)a do
+      post_attrs = mock_attrs(:post, %{community_id: community.id, is_question: true})
+      {:ok, post} = CMS.create_article(community, :post, post_attrs, user)
+
+      {:ok, post} = ORM.find(Post, post.id, preload: [author: :user])
+      post_author = post.author.user
+
+      {:ok, comment1} = CMS.create_article_comment(:post, post.id, "comment", post_author)
+      {:ok, comment2} = CMS.create_article_comment(:post, post.id, "comment", post_author)
+
+      {:ok, _comment} = CMS.mark_comment_solution(comment1.id, post_author)
+      {:ok, comment2} = CMS.mark_comment_solution(comment2.id, post_author)
+
+      answers =
+        from(c in ArticleComment, where: c.post_id == ^post.id and c.is_solution == true)
+        |> Repo.all()
+
+      assert answers |> length == 1
+      assert answers |> List.first() |> Map.get(:id) == comment2.id
+    end
   end
 end