✨ Add commit depth support for GitLab (#3672)

* feat: Integrated paging to allow for querying based on the --commit-depth value provided

Signed-off-by: Allen Shearin <allen.p.shearin@gmail.com>

* fix: rework git commits changes for readability

Signed-off-by: Allen Shearin <allen.p.shearin@gmail.com>

* fix: add additional commit depth test

Signed-off-by: Allen Shearin <allen.p.shearin@gmail.com>

---------

Signed-off-by: Allen Shearin <allen.p.shearin@gmail.com>

clients/gitlabrepo/client.go

@@ -114,7 +114,7 @@ func (client *Client) InitRepo(inputRepo clients.Repo, commitSHA string, commitD
 	client.contributors.init(client.repourl)
 
 	// Init commitsHandler
-	client.commits.init(client.repourl)
+	client.commits.init(client.repourl, client.commitDepth)
 
 	// Init branchesHandler
 	client.branches.init(client.repourl)

clients/gitlabrepo/commits.go

@@ -27,31 +27,56 @@ import (
 )
 
 type commitsHandler struct {
-	glClient   *gitlab.Client
-	once       *sync.Once
-	errSetup   error
-	repourl    *repoURL
-	commitsRaw []*gitlab.Commit
+	glClient    *gitlab.Client
+	once        *sync.Once
+	errSetup    error
+	repourl     *repoURL
+	commitsRaw  []*gitlab.Commit
+	commitDepth int
 }
 
-func (handler *commitsHandler) init(repourl *repoURL) {
+func (handler *commitsHandler) init(repourl *repoURL, commitDepth int) {
 	handler.repourl = repourl
 	handler.errSetup = nil
 	handler.once = new(sync.Once)
+	handler.commitDepth = commitDepth
 }
 
 func (handler *commitsHandler) setup() error {
 	handler.once.Do(func() {
-		commits, _, err := handler.glClient.Commits.ListCommits(
-			handler.repourl.projectID,
-			&gitlab.ListCommitsOptions{
-				RefName: &handler.repourl.commitSHA,
-			},
-		)
-		if err != nil {
-			handler.errSetup = fmt.Errorf("request for commits failed with %w", err)
-			return
+		var commits []*gitlab.Commit
+		opt := gitlab.ListOptions{
+			Page:    1,
+			PerPage: handler.commitDepth,
 		}
+
+		for {
+			c, resp, err := handler.glClient.Commits.ListCommits(handler.repourl.projectID,
+				&gitlab.ListCommitsOptions{
+					RefName:     &handler.repourl.commitSHA,
+					ListOptions: opt,
+				})
+			if err != nil {
+				handler.errSetup = fmt.Errorf("request for commits failed with %w", err)
+				return
+			}
+
+			commits = append(commits, c...)
+
+			if len(commits) >= handler.commitDepth {
+				commits = commits[:handler.commitDepth]
+				break
+			}
+
+			// Exit the loop when we've seen all pages.
+			if resp.NextPage == 0 {
+				break
+			}
+
+			// Update the page number to get the next page.
+			opt.Page = resp.NextPage
+		}
+
 		handler.commitsRaw = commits
 		if handler.repourl.commitSHA != clients.HeadSHA {
 			//nolint:lll

clients/gitlabrepo/commits_test.go

@@ -15,7 +15,13 @@
 package gitlabrepo
 
 import (
+	"net/http"
 	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/xanzy/go-gitlab"
+
+	"github.com/ossf/scorecard/v4/clients"
 )
 
 func TestParsingEmail(t *testing.T) {
@@ -56,3 +62,78 @@ func TestParsingEmail(t *testing.T) {
 		})
 	}
 }
+
+func TestListRawCommits(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		name        string
+		commitsPath string
+		commitDepth int
+		want        int
+		wantErr     bool
+	}{
+		{
+			name:        "commits to non-default depth",
+			commitsPath: "./testdata/valid-commits",
+			commitDepth: 17,
+			want:        17,
+			wantErr:     false,
+		},
+		{
+			name:        "commits to default depth",
+			commitsPath: "./testdata/valid-commits",
+			commitDepth: 30,
+			want:        30,
+			wantErr:     false,
+		},
+		{
+			name:        "request more commits than exist in the repo",
+			commitsPath: "./testdata/valid-commits",
+			commitDepth: 60,
+			want:        32,
+			wantErr:     false,
+		},
+		{
+			name:        "failure fetching commits",
+			commitsPath: "./testdata/invalid-commits",
+			commitDepth: 30,
+			want:        0,
+			wantErr:     true,
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			httpClient := &http.Client{
+				Transport: suffixStubTripper{
+					responsePaths: map[string]string{
+						"commits": tt.commitsPath, // corresponds to projects/<id>/repository/commits
+					},
+				},
+			}
+			client, err := gitlab.NewClient("", gitlab.WithHTTPClient(httpClient))
+			if err != nil {
+				t.Fatalf("gitlab.NewClient error: %v", err)
+			}
+			handler := &commitsHandler{
+				glClient: client,
+			}
+
+			repoURL := repoURL{
+				owner:     "ossf-tests",
+				commitSHA: clients.HeadSHA,
+			}
+
+			handler.init(&repoURL, tt.commitDepth)
+			commits, err := handler.listRawCommits()
+			if (err != nil) != tt.wantErr {
+				t.Fatalf("listIssues error: %v, wantedErr: %t", err, tt.wantErr)
+			}
+			if !cmp.Equal(len(commits), tt.want) {
+				t.Errorf("listCommits() = %v, want %v", len(commits), cmp.Diff(len(commits), tt.want))
+			}
+		})
+	}
+}