adding support for GitHub v3 delete comment (#2540)

src/main/scala/gitbucket/core/controller/api/ApiIssueCommentControllerBase.scala

@@ -4,6 +4,7 @@ import gitbucket.core.controller.{Context, ControllerBase}
 import gitbucket.core.service._
 import gitbucket.core.util.Implicits._
 import gitbucket.core.util.{ReadableUsersAuthenticator, ReferrerAuthenticator, RepositoryName}
+import org.scalatra.{ActionResult, NoContent}
 
 trait ApiIssueCommentControllerBase extends ControllerBase {
   self: AccountService
@@ -112,8 +113,30 @@ trait ApiIssueCommentControllerBase extends ControllerBase {
 
   /*
    * vi. Delete a comment
-   * https://developer.github.com/v3/issues/comments/#delete-a-comment
+   * https://docs.github.com/en/rest/reference/issues#delete-an-issue-comment
+   *
    */
+  delete("/api/v3/repos/{owner}/{repo}/issues/comments/:id")(readableUsersOnly { repository =>
+    val maybeDeleteResponse: Option[Either[ActionResult, Option[Int]]] =
+      for {
+        commentId <- params("id").toIntOpt
+        comment <- getComment(repository.owner, repository.name, commentId.toString)
+        issue <- getIssue(repository.owner, repository.name, comment.issueId.toString)
+      } yield {
+        if (isEditable(repository.owner, repository.name, comment.commentedUserName)) {
+          val maybeDeletedComment = deleteCommentByApi(repository, comment, issue)
+          Right(maybeDeletedComment.map(_.commentId))
+        } else {
+          Left(Unauthorized())
+        }
+      }
+    maybeDeleteResponse
+      .map {
+        case Right(maybeDeletedCommentId) => maybeDeletedCommentId.getOrElse(NotFound())
+        case Left(err)                    => err
+      }
+      .getOrElse(NotFound())
+  })
 
   private def isEditable(owner: String, repository: String, author: String)(implicit context: Context): Boolean =
     hasDeveloperRole(owner, repository, context.loginAccount) || author == context.loginAccount.get.userName

src/main/scala/gitbucket/core/plugin/IssueHook.scala

@@ -13,6 +13,10 @@ trait IssueHook {
     implicit session: Session,
     context: Context
   ): Unit = ()
+  def deletedComment(commentId: Int, issue: Issue, repository: RepositoryInfo)(
+    implicit session: Session,
+    context: Context
+  ): Unit = ()
   def updatedComment(commentId: Int, content: String, issue: Issue, repository: RepositoryInfo)(
     implicit session: Session,
     context: Context

src/main/scala/gitbucket/core/service/HandleCommentService.scala

@@ -1,7 +1,7 @@
 package gitbucket.core.service
 
 import gitbucket.core.controller.Context
-import gitbucket.core.model.Issue
+import gitbucket.core.model.{Issue, IssueComment}
 import gitbucket.core.model.Profile.profile.blockingApi._
 import gitbucket.core.model.activity.{
   CloseIssueInfo,
@@ -11,7 +11,8 @@ import gitbucket.core.model.activity.{
   ReopenIssueInfo,
   ReopenPullRequestInfo
 }
-import gitbucket.core.plugin.PluginRegistry
+import gitbucket.core.plugin.{IssueHook, PluginRegistry}
+import gitbucket.core.service.RepositoryService.RepositoryInfo
 import gitbucket.core.util.SyntaxSugars._
 import gitbucket.core.util.Implicits._
 
@@ -135,6 +136,24 @@ trait HandleCommentService {
     }
   }
 
+  def deleteCommentByApi(repoInfo: RepositoryInfo, comment: IssueComment, issue: Issue)(
+    implicit context: Context,
+    s: Session
+  ): Option[IssueComment] = context.loginAccount.flatMap { _ =>
+    comment.action match {
+      case "comment" =>
+        val deleteResult = deleteComment(comment.issueId, comment.commentId)
+        val registry = PluginRegistry()
+        val hooks: Seq[IssueHook] = if (issue.isPullRequest) registry.getPullRequestHooks else registry.getIssueHooks
+        hooks.foreach(_.deletedComment(comment.commentId, issue, repoInfo))
+        deleteResult match {
+          case n if n > 0 => Some(comment)
+          case _          => None
+        }
+      case _ => None
+    }
+  }
+
   def updateCommentByApi(
     repository: RepositoryService.RepositoryInfo,
     issue: Issue,