Make the github migration less rate limit waiting to get comment per page from repository but not per issue (#16070)

* Make the github migration less rate limit waiting to get comment per page from repository but not per issue

* Fix lint

* adjust Downloader interface

* Fix missed reviews

* Fix test

* Remove unused struct

3 files changed, 20 insertions, 6 deletions

diff --git a/modules/migrations/base/downloader.go b/modules/migrations/base/downloader.go
index 919f4b52a0..2388b2dd6e 100644
--- a/modules/migrations/base/downloader.go
+++ b/modules/migrations/base/downloader.go
@@ -11,6 +11,13 @@ import (
 	"code.gitea.io/gitea/modules/structs"
 )
 
+// GetCommentOptions represents an options for get comment
+type GetCommentOptions struct {
+	IssueNumber int64
+	Page        int
+	PageSize    int
+}
+
 // Downloader downloads the site repo informations
 type Downloader interface {
 	SetContext(context.Context)
@@ -20,7 +27,8 @@ type Downloader interface {
 	GetReleases() ([]*Release, error)
 	GetLabels() ([]*Label, error)
 	GetIssues(page, perPage int) ([]*Issue, bool, error)
-	GetComments(issueNumber int64) ([]*Comment, error)
+	GetComments(opts GetCommentOptions) ([]*Comment, bool, error)
+	SupportGetRepoComments() bool
 	GetPullRequests(page, perPage int) ([]*PullRequest, bool, error)
 	GetReviews(pullRequestNumber int64) ([]*Review, error)
 	FormatCloneURL(opts MigrateOptions, remoteAddr string) (string, error)
diff --git a/modules/migrations/base/null_downloader.go b/modules/migrations/base/null_downloader.go
index a93c20339b..53a536709d 100644
--- a/modules/migrations/base/null_downloader.go
+++ b/modules/migrations/base/null_downloader.go
@@ -51,8 +51,8 @@ func (n NullDownloader) GetIssues(page, perPage int) ([]*Issue, bool, error) {
 }
 
 // GetComments returns comments according issueNumber
-func (n NullDownloader) GetComments(issueNumber int64) ([]*Comment, error) {
-	return nil, &ErrNotSupported{Entity: "Comments"}
+func (n NullDownloader) GetComments(GetCommentOptions) ([]*Comment, bool, error) {
+	return nil, false, &ErrNotSupported{Entity: "Comments"}
 }
 
 // GetPullRequests returns pull requests according page and perPage
@@ -80,3 +80,8 @@ func (n NullDownloader) FormatCloneURL(opts MigrateOptions, remoteAddr string) (
 	}
 	return remoteAddr, nil
 }
+
+// SupportGetRepoComments return true if it supports get repo comments
+func (n NullDownloader) SupportGetRepoComments() bool {
+	return false
+}
diff --git a/modules/migrations/base/retry_downloader.go b/modules/migrations/base/retry_downloader.go
index 82a038b98b..e6c80038f1 100644
--- a/modules/migrations/base/retry_downloader.go
+++ b/modules/migrations/base/retry_downloader.go
@@ -150,18 +150,19 @@ func (d *RetryDownloader) GetIssues(page, perPage int) ([]*Issue, bool, error) {
 }
 
 // GetComments returns a repository's comments with retry
-func (d *RetryDownloader) GetComments(issueNumber int64) ([]*Comment, error) {
+func (d *RetryDownloader) GetComments(opts GetCommentOptions) ([]*Comment, bool, error) {
 	var (
 		comments []*Comment
+		isEnd    bool
 		err      error
 	)
 
 	err = d.retry(func() error {
-		comments, err = d.Downloader.GetComments(issueNumber)
+		comments, isEnd, err = d.Downloader.GetComments(opts)
 		return err
 	})
 
-	return comments, err
+	return comments, isEnd, err
 }
 
 // GetPullRequests returns a repository's pull requests with retry