New webhook trigger for receiving Pull Request review requests (#24481)

close https://github.com/go-gitea/gitea/issues/16321

Provided a webhook trigger for requesting someone to review the Pull
Request.

Some modifications have been made to the returned `PullRequestPayload`
based on the GitHub webhook settings, including:
- add a description of the current reviewer object as
`RequestedReviewer` .
- setting the action to either **review_requested** or
**review_request_removed** based on the operation.
- adding the `RequestedReviewers` field to the issues_model.PullRequest.
This field will be loaded into the PullRequest through
`LoadRequestedReviewers()` when `ToAPIPullRequest` is called.

After the Pull Request is merged, I will supplement the relevant
documentation.

4 files changed, 62 insertions, 25 deletions

diff --git a/services/convert/pull.go b/services/convert/pull.go
index 4989e82cd4..598187ca6e 100644
--- a/services/convert/pull.go
+++ b/services/convert/pull.go
@@ -88,6 +88,14 @@ func ToAPIPullRequest(ctx context.Context, pr *issues_model.PullRequest, doer *u
 		},
 	}
 
+	if err = pr.LoadRequestedReviewers(ctx); err != nil {
+		log.Error("LoadRequestedReviewers[%d]: %v", pr.ID, err)
+		return nil
+	}
+	for _, reviewer := range pr.RequestedReviewers {
+		apiPullRequest.RequestedReviewers = append(apiPullRequest.RequestedReviewers, ToUser(ctx, reviewer, nil))
+	}
+
 	if pr.Issue.ClosedUnix != 0 {
 		apiPullRequest.Closed = pr.Issue.ClosedUnix.AsTimePtr()
 	}
diff --git a/services/forms/repo_form.go b/services/forms/repo_form.go
index cacfb64b17..8108a55f7a 100644
--- a/services/forms/repo_form.go
+++ b/services/forms/repo_form.go
@@ -228,30 +228,31 @@ func (f *ProtectBranchForm) Validate(req *http.Request, errs binding.Errors) bin
 
 // WebhookForm form for changing web hook
 type WebhookForm struct {
-	Events               string
-	Create               bool
-	Delete               bool
-	Fork                 bool
-	Issues               bool
-	IssueAssign          bool
-	IssueLabel           bool
-	IssueMilestone       bool
-	IssueComment         bool
-	Release              bool
-	Push                 bool
-	PullRequest          bool
-	PullRequestAssign    bool
-	PullRequestLabel     bool
-	PullRequestMilestone bool
-	PullRequestComment   bool
-	PullRequestReview    bool
-	PullRequestSync      bool
-	Wiki                 bool
-	Repository           bool
-	Package              bool
-	Active               bool
-	BranchFilter         string `binding:"GlobPattern"`
-	AuthorizationHeader  string
+	Events                   string
+	Create                   bool
+	Delete                   bool
+	Fork                     bool
+	Issues                   bool
+	IssueAssign              bool
+	IssueLabel               bool
+	IssueMilestone           bool
+	IssueComment             bool
+	Release                  bool
+	Push                     bool
+	PullRequest              bool
+	PullRequestAssign        bool
+	PullRequestLabel         bool
+	PullRequestMilestone     bool
+	PullRequestComment       bool
+	PullRequestReview        bool
+	PullRequestSync          bool
+	PullRequestReviewRequest bool
+	Wiki                     bool
+	Repository               bool
+	Package                  bool
+	Active                   bool
+	BranchFilter             string `binding:"GlobPattern"`
+	AuthorizationHeader      string
 }
 
 // PushOnly if the hook will be triggered when push
diff --git a/services/webhook/notifier.go b/services/webhook/notifier.go
index 1f7cb8d988..bd25e20805 100644
--- a/services/webhook/notifier.go
+++ b/services/webhook/notifier.go
@@ -719,6 +719,34 @@ func (m *webhookNotifier) NotifyPullRequestReview(ctx context.Context, pr *issue
 	}
 }
 
+func (m *webhookNotifier) NotifyPullReviewRequest(ctx context.Context, doer *user_model.User, issue *issues_model.Issue, reviewer *user_model.User, isRequest bool, comment *issues_model.Comment) {
+	if !issue.IsPull {
+		log.Warn("NotifyPullReviewRequest: issue is not a pull request: %v", issue.ID)
+		return
+	}
+	mode, _ := access_model.AccessLevelUnit(ctx, doer, issue.Repo, unit.TypePullRequests)
+	if err := issue.LoadPullRequest(ctx); err != nil {
+		log.Error("LoadPullRequest failed: %v", err)
+		return
+	}
+	apiPullRequest := &api.PullRequestPayload{
+		Index:             issue.Index,
+		PullRequest:       convert.ToAPIPullRequest(ctx, issue.PullRequest, nil),
+		RequestedReviewer: convert.ToUser(ctx, reviewer, nil),
+		Repository:        convert.ToRepo(ctx, issue.Repo, mode),
+		Sender:            convert.ToUser(ctx, doer, nil),
+	}
+	if isRequest {
+		apiPullRequest.Action = api.HookIssueReviewRequested
+	} else {
+		apiPullRequest.Action = api.HookIssueReviewRequestRemoved
+	}
+	if err := PrepareWebhooks(ctx, EventSource{Repository: issue.Repo}, webhook_module.HookEventPullRequestReviewRequest, apiPullRequest); err != nil {
+		log.Error("PrepareWebhooks [review_requested: %v]: %v", isRequest, err)
+		return
+	}
+}
+
 func (m *webhookNotifier) NotifyCreateRef(ctx context.Context, pusher *user_model.User, repo *repo_model.Repository, refType, refFullName, refID string) {
 	apiPusher := convert.ToUser(ctx, pusher, nil)
 	apiRepo := convert.ToRepo(ctx, repo, perm.AccessModeNone)
diff --git a/services/webhook/payloader.go b/services/webhook/payloader.go
index 9eff25628b..d53e65fa5e 100644
--- a/services/webhook/payloader.go
+++ b/services/webhook/payloader.go
@@ -43,7 +43,7 @@ func convertPayloader(s PayloadConvertor, p api.Payloader, event webhook_module.
 	case webhook_module.HookEventPush:
 		return s.Push(p.(*api.PushPayload))
 	case webhook_module.HookEventPullRequest, webhook_module.HookEventPullRequestAssign, webhook_module.HookEventPullRequestLabel,
-		webhook_module.HookEventPullRequestMilestone, webhook_module.HookEventPullRequestSync:
+		webhook_module.HookEventPullRequestMilestone, webhook_module.HookEventPullRequestSync, webhook_module.HookEventPullRequestReviewRequest:
 		return s.PullRequest(p.(*api.PullRequestPayload))
 	case webhook_module.HookEventPullRequestReviewApproved, webhook_module.HookEventPullRequestReviewRejected, webhook_module.HookEventPullRequestReviewComment:
 		return s.Review(p.(*api.PullRequestPayload), event)