Add API to get issue/pull comments and events (timeline) (#17403)

* Add API to get issue/pull comments and events (timeline)
Adds an API to get both comments and events in one endpoint with all required data.
Closes go-gitea/gitea#13250

* Fix swagger

* Don't show code comments (use review api instead)

* fmt

* Fix comment

* Time -> TrackedTime

* Use var directly

* Add logger

* Fix lint

* Fix test

* Add comments

* fmt

* [test] get issue directly by ID

* Update test

* Add description for changed refs

* Fix build issues + lint

* Fix build

* Use string enums

* Update swagger

* Support `page` and `limit` params

* fmt + swagger

* Use global slices

Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

3 files changed, 199 insertions, 0 deletions

diff --git a/modules/convert/issue_comment.go b/modules/convert/issue_comment.go
index 1610b9f0d8..caba2b506e 100644
--- a/modules/convert/issue_comment.go
+++ b/modules/convert/issue_comment.go
@@ -6,6 +6,9 @@ package convert
 
 import (
 	"code.gitea.io/gitea/models"
+	repo_model "code.gitea.io/gitea/models/repo"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/log"
 	api "code.gitea.io/gitea/modules/structs"
 )
 
@@ -22,3 +25,143 @@ func ToComment(c *models.Comment) *api.Comment {
 		Updated:  c.UpdatedUnix.AsTime(),
 	}
 }
+
+// ToTimelineComment converts a models.Comment to the api.TimelineComment format
+func ToTimelineComment(c *models.Comment, doer *user_model.User) *api.TimelineComment {
+	err := c.LoadMilestone()
+	if err != nil {
+		log.Error("LoadMilestone: %v", err)
+		return nil
+	}
+
+	err = c.LoadAssigneeUserAndTeam()
+	if err != nil {
+		log.Error("LoadAssigneeUserAndTeam: %v", err)
+		return nil
+	}
+
+	err = c.LoadResolveDoer()
+	if err != nil {
+		log.Error("LoadResolveDoer: %v", err)
+		return nil
+	}
+
+	err = c.LoadDepIssueDetails()
+	if err != nil {
+		log.Error("LoadDepIssueDetails: %v", err)
+		return nil
+	}
+
+	err = c.LoadTime()
+	if err != nil {
+		log.Error("LoadTime: %v", err)
+		return nil
+	}
+
+	err = c.LoadLabel()
+	if err != nil {
+		log.Error("LoadLabel: %v", err)
+		return nil
+	}
+
+	comment := &api.TimelineComment{
+		ID:       c.ID,
+		Type:     c.Type.String(),
+		Poster:   ToUser(c.Poster, nil),
+		HTMLURL:  c.HTMLURL(),
+		IssueURL: c.IssueURL(),
+		PRURL:    c.PRURL(),
+		Body:     c.Content,
+		Created:  c.CreatedUnix.AsTime(),
+		Updated:  c.UpdatedUnix.AsTime(),
+
+		OldProjectID: c.OldProjectID,
+		ProjectID:    c.ProjectID,
+
+		OldTitle: c.OldTitle,
+		NewTitle: c.NewTitle,
+
+		OldRef: c.OldRef,
+		NewRef: c.NewRef,
+
+		RefAction:    c.RefAction.String(),
+		RefCommitSHA: c.CommitSHA,
+
+		ReviewID: c.ReviewID,
+
+		RemovedAssignee: c.RemovedAssignee,
+	}
+
+	if c.OldMilestone != nil {
+		comment.OldMilestone = ToAPIMilestone(c.OldMilestone)
+	}
+	if c.Milestone != nil {
+		comment.Milestone = ToAPIMilestone(c.Milestone)
+	}
+
+	if c.Time != nil {
+		comment.TrackedTime = ToTrackedTime(c.Time)
+	}
+
+	if c.RefIssueID != 0 {
+		issue, err := models.GetIssueByID(c.RefIssueID)
+		if err != nil {
+			log.Error("GetIssueByID(%d): %v", c.RefIssueID, err)
+			return nil
+		}
+		comment.RefIssue = ToAPIIssue(issue)
+	}
+
+	if c.RefCommentID != 0 {
+		com, err := models.GetCommentByID(c.RefCommentID)
+		if err != nil {
+			log.Error("GetCommentByID(%d): %v", c.RefCommentID, err)
+			return nil
+		}
+		err = com.LoadPoster()
+		if err != nil {
+			log.Error("LoadPoster: %v", err)
+			return nil
+		}
+		comment.RefComment = ToComment(com)
+	}
+
+	if c.Label != nil {
+		var org *user_model.User
+		var repo *repo_model.Repository
+		if c.Label.BelongsToOrg() {
+			var err error
+			org, err = user_model.GetUserByID(c.Label.OrgID)
+			if err != nil {
+				log.Error("GetUserByID(%d): %v", c.Label.OrgID, err)
+				return nil
+			}
+		}
+		if c.Label.BelongsToRepo() {
+			var err error
+			repo, err = repo_model.GetRepositoryByID(c.Label.RepoID)
+			if err != nil {
+				log.Error("GetRepositoryByID(%d): %v", c.Label.RepoID, err)
+				return nil
+			}
+		}
+		comment.Label = ToLabel(c.Label, repo, org)
+	}
+
+	if c.Assignee != nil {
+		comment.Assignee = ToUser(c.Assignee, nil)
+	}
+	if c.AssigneeTeam != nil {
+		comment.AssigneeTeam = ToTeam(c.AssigneeTeam)
+	}
+
+	if c.ResolveDoer != nil {
+		comment.ResolveDoer = ToUser(c.ResolveDoer, nil)
+	}
+
+	if c.DependentIssue != nil {
+		comment.DependentIssue = ToAPIIssue(c.DependentIssue)
+	}
+
+	return comment
+}
diff --git a/modules/references/references.go b/modules/references/references.go
index cfc01cd4c0..74837b8553 100644
--- a/modules/references/references.go
+++ b/modules/references/references.go
@@ -49,6 +49,13 @@ var (
 	giteaHostInit         sync.Once
 	giteaHost             string
 	giteaIssuePullPattern *regexp.Regexp
+
+	actionStrings = []string{
+		"none",
+		"closes",
+		"reopens",
+		"neutered",
+	}
 )
 
 // XRefAction represents the kind of effect a cross reference has once is resolved
@@ -65,6 +72,10 @@ const (
 	XRefActionNeutered // 3
 )
 
+func (a XRefAction) String() string {
+	return actionStrings[a]
+}
+
 // IssueReference contains an unverified cross-reference to a local issue or pull request
 type IssueReference struct {
 	Index   int64
diff --git a/modules/structs/issue_comment.go b/modules/structs/issue_comment.go
index 0c8ac20017..e13ec05d01 100644
--- a/modules/structs/issue_comment.go
+++ b/modules/structs/issue_comment.go
@@ -35,3 +35,48 @@ type EditIssueCommentOption struct {
 	// required: true
 	Body string `json:"body" binding:"Required"`
 }
+
+// TimelineComment represents a timeline comment (comment of any type) on a commit or issue
+type TimelineComment struct {
+	ID   int64  `json:"id"`
+	Type string `json:"type"`
+
+	HTMLURL  string `json:"html_url"`
+	PRURL    string `json:"pull_request_url"`
+	IssueURL string `json:"issue_url"`
+	Poster   *User  `json:"user"`
+	Body     string `json:"body"`
+	// swagger:strfmt date-time
+	Created time.Time `json:"created_at"`
+	// swagger:strfmt date-time
+	Updated time.Time `json:"updated_at"`
+
+	OldProjectID int64        `json:"old_project_id"`
+	ProjectID    int64        `json:"project_id"`
+	OldMilestone *Milestone   `json:"old_milestone"`
+	Milestone    *Milestone   `json:"milestone"`
+	TrackedTime  *TrackedTime `json:"tracked_time"`
+	OldTitle     string       `json:"old_title"`
+	NewTitle     string       `json:"new_title"`
+	OldRef       string       `json:"old_ref"`
+	NewRef       string       `json:"new_ref"`
+
+	RefIssue   *Issue   `json:"ref_issue"`
+	RefComment *Comment `json:"ref_comment"`
+	RefAction  string   `json:"ref_action"`
+	// commit SHA where issue/PR was referenced
+	RefCommitSHA string `json:"ref_commit_sha"`
+
+	ReviewID int64 `json:"review_id"`
+
+	Label *Label `json:"label"`
+
+	Assignee     *User `json:"assignee"`
+	AssigneeTeam *Team `json:"assignee_team"`
+	// whether the assignees were removed or added
+	RemovedAssignee bool `json:"removed_assignee"`
+
+	ResolveDoer *User `json:"resolve_doer"`
+
+	DependentIssue *Issue `json:"dependent_issue"`
+}