🐛 Support self-hosted GitLab instances where base URL has a path component

README.md

@@ -437,6 +437,17 @@ scorecard --repo gitlab.com/<org>/<project>/<subproject>
 
 For an example of using Scorecard in GitLab CI/CD, see [here](https://gitlab.com/ossf-test/scorecard-pipeline-example).
 
+###### Self Hosted Editions
+While we focus on GitLab.com support, Scorecard also works with self-hosted GitLab installations.
+If your platform is hosted at a subdomain (e.g. `gitlab.foo.com`), Scorecard should work out of the box.
+If your platform is hosted at some slug (e.g. `foo.com/bar/`), you will need to set the `GL_HOST` environment variable.
+
+```bash
+export GITLAB_AUTH_TOKEN=glpat-xxxx
+export GL_HOST=foo.com/bar
+scorecard --repo foo.com/bar/<org>/<project>
+```
+
 ##### Using GitHub Enterprise Server (GHES) based Repository
 
 To use a GitHub Enterprise host `github.corp.com`, use the `GH_HOST` environment variable.

clients/gitlabrepo/repo.go

@@ -20,6 +20,7 @@
 	"errors"
 	"fmt"
 	"net/url"
+	"os"
 	"strings"
 
 	"github.com/xanzy/go-gitlab"
@@ -61,14 +62,26 @@
 		t = input
 	}
 
-	// Allow skipping scheme for ease-of-use, default to https.
-	if !strings.Contains(t, "://") {
-		t = "https://" + t
+	u, err := url.Parse(withDefaultScheme(t))
+	if err != nil {
+		return sce.WithMessage(sce.ErrScorecardInternal, fmt.Sprintf("url.Parse: %v", err))
 	}
 
-	u, e := url.Parse(t)
-	if e != nil {
-		return sce.WithMessage(sce.ErrScorecardInternal, fmt.Sprintf("url.Parse: %v", e))
+	// fixup the URL, for situations where GL_HOST contains part of the path
+	// https://github.com/ossf/scorecard/issues/3696
+	if h := os.Getenv("GL_HOST"); h != "" {
+		hostURL, err := url.Parse(withDefaultScheme(h))
+		if err != nil {
+			return sce.WithMessage(sce.ErrScorecardInternal, fmt.Sprintf("url.Parse GL_HOST: %v", err))
+		}
+
+		// only modify behavior of repos which fall under GL_HOST
+		if hostURL.Host == u.Host {
+			// without the scheme and without trailing slashes
+			u.Host = hostURL.Host + strings.TrimRight(hostURL.Path, "/")
+			// remove any part of the path which belongs to the host
+			u.Path = strings.TrimPrefix(u.Path, hostURL.Path)
+		}
 	}
 
 	const splitLen = 2
@@ -81,6 +94,14 @@
 	return nil
 }
 
+// Allow skipping scheme for ease-of-use, default to https.
+func withDefaultScheme(uri string) string {
+	if strings.Contains(uri, "://") {
+		return uri
+	}
+	return "https://" + uri
+}
+
 // URI implements Repo.URI().
 func (r *repoURL) URI() string {
 	return fmt.Sprintf("%s/%s/%s", r.host, r.owner, r.project)
@@ -105,7 +126,9 @@
 		return fmt.Errorf("%w: %s", errInvalidGitlabRepoURL, r.host)
 	}
 
-	client, err := gitlab.NewClient("", gitlab.WithBaseURL(fmt.Sprintf("%s://%s", r.scheme, r.host)))
+	token := os.Getenv("GITLAB_AUTH_TOKEN")
+	baseURL := r.Host()
+	client, err := gitlab.NewClient(token, gitlab.WithBaseURL(baseURL))
 	if err != nil {
 		return sce.WithMessage(err,
 			fmt.Sprintf("couldn't create gitlab client for %s", r.host),

clients/gitlabrepo/repo_test.go

@@ -178,3 +178,83 @@ func TestRepoURL_MakeGitLabRepo(t *testing.T) {
 		}
 	}
 }
+
+//nolint:paralleltest // uses t.Setenv, can't be parallelized
+func TestRepoURL_parse_GL_HOST(t *testing.T) {
+	tests := []struct {
+		name                 string
+		url                  string
+		host, owner, project string
+		glHost               string
+		wantErr              bool
+	}{
+		{
+			name:    "GL_HOST ends with slash",
+			glHost:  "https://foo.com/gitlab/",
+			url:     "foo.com/gitlab/ssdlc/scorecard-scanner",
+			host:    "foo.com/gitlab",
+			owner:   "ssdlc",
+			project: "scorecard-scanner",
+		},
+		{
+			name:    "GL_HOST doesn't end with slash",
+			glHost:  "https://foo.com/gitlab",
+			url:     "foo.com/gitlab/ssdlc/scorecard-scanner",
+			host:    "foo.com/gitlab",
+			owner:   "ssdlc",
+			project: "scorecard-scanner",
+		},
+		{
+			name:    "GL_HOST doesn't match url",
+			glHost:  "https://foo.com/gitlab",
+			url:     "bar.com/gitlab/ssdlc/scorecard-scanner",
+			host:    "bar.com",
+			owner:   "gitlab",
+			project: "ssdlc/scorecard-scanner",
+		},
+		{
+			name:    "GL_HOST has no path component",
+			glHost:  "https://foo.com",
+			url:     "foo.com/ssdlc/scorecard-scanner",
+			host:    "foo.com",
+			owner:   "ssdlc",
+			project: "scorecard-scanner",
+		},
+		{
+			name:    "GL_HOST path has multiple slashes",
+			glHost:  "https://foo.com/bar/baz/",
+			url:     "foo.com/bar/baz/ssdlc/scorecard-scanner",
+			host:    "foo.com/bar/baz",
+			owner:   "ssdlc",
+			project: "scorecard-scanner",
+		},
+		{
+			name:    "GL_HOST has no scheme",
+			glHost:  "foo.com/bar/",
+			url:     "foo.com/bar/ssdlc/scorecard-scanner",
+			host:    "foo.com/bar",
+			owner:   "ssdlc",
+			project: "scorecard-scanner",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Setenv("GL_HOST", tt.glHost)
+			var r repoURL
+			err := r.parse(tt.url)
+			if (err != nil) != tt.wantErr {
+				t.Fatalf("wanted err: %t, got: %v", tt.wantErr, err)
+			}
+			if r.host != tt.host {
+				t.Errorf("got host: %s, want: %s", r.host, tt.host)
+			}
+			if r.owner != tt.owner {
+				t.Errorf("got owner: %s, want: %s", r.owner, tt.owner)
+			}
+			if r.project != tt.project {
+				t.Errorf("got project: %s, want: %s", r.project, tt.project)
+			}
+		})
+	}
+}