From e314fb5c6bf66b78444b0132525c223f7ea6b87d Mon Sep 17 00:00:00 2001
From: Yusuke Kuoka <ykuoka@gmail.com>
Date: Sun, 7 Feb 2021 17:56:12 +0900
Subject: [PATCH] fix: Paginate ListRepositoryWorkflowRuns

When we used `QueuedAndInProgressWorkflowRuns`-based autoscaling, it only fetched and considered only the first 30 workflow runs at the reconcilation time. This may have resulted in unreliable scaling behaviour, like scale-in/out not happening when it was expected.
---
 controllers/autoscaling.go |  4 ++--
 github/github.go           | 28 ++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/controllers/autoscaling.go b/controllers/autoscaling.go
index 526ada57e8..f87d692381 100644
--- a/controllers/autoscaling.go
+++ b/controllers/autoscaling.go
@@ -138,12 +138,12 @@ func (r *HorizontalRunnerAutoscalerReconciler) calculateReplicasByQueuedAndInPro
 
 	for _, repo := range repos {
 		user, repoName := repo[0], repo[1]
-		list, _, err := r.GitHubClient.Actions.ListRepositoryWorkflowRuns(context.TODO(), user, repoName, nil)
+		workflowRuns, err := r.GitHubClient.ListRepositoryWorkflowRuns(context.TODO(), user, repoName)
 		if err != nil {
 			return nil, err
 		}
 
-		for _, run := range list.WorkflowRuns {
+		for _, run := range workflowRuns {
 			total++
 
 			// In May 2020, there are only 3 statuses.
diff --git a/github/github.go b/github/github.go
index 327c2efc9a..9bd4b73a60 100644
--- a/github/github.go
+++ b/github/github.go
@@ -207,6 +207,34 @@ func (c *Client) listRunners(ctx context.Context, enterprise, org, repo string,
 	return c.Client.Enterprise.ListRunners(ctx, enterprise, opts)
 }
 
+func (c *Client) ListRepositoryWorkflowRuns(ctx context.Context, user string, repoName string) ([]*github.WorkflowRun, error) {
+	c.Client.Actions.ListRepositoryWorkflowRuns(ctx, user, repoName, nil)
+
+	var workflowRuns []*github.WorkflowRun
+
+	opts := github.ListWorkflowRunsOptions{
+		ListOptions: github.ListOptions{
+			PerPage: 100,
+		},
+	}
+
+	for {
+		list, res, err := c.Client.Actions.ListRepositoryWorkflowRuns(ctx, user, repoName, &opts)
+
+		if err != nil {
+			return workflowRuns, fmt.Errorf("failed to list workflow runs: %v", err)
+		}
+
+		workflowRuns = append(workflowRuns, list.WorkflowRuns...)
+		if res.NextPage == 0 {
+			break
+		}
+		opts.Page = res.NextPage
+	}
+
+	return workflowRuns, nil
+}
+
 // Validates enterprise, organisation and repo arguments. Both are optional, but at least one should be specified
 func getEnterpriseOrganisationAndRepo(enterprise, org, repo string) (string, string, string, error) {
 	if len(repo) > 0 {