Add repo signing key lookup

Co-Authored-By: Virgil <virgil@lethean.io>

docs/api-contract.md

@@ -182,6 +182,7 @@ Coverage notes: rows list direct tests when a symbol is named in test names or r
 | method | RepoService.AcceptTransfer | `func (s *RepoService) AcceptTransfer(ctx context.Context, owner, repo string) error` | AcceptTransfer accepts a pending repository transfer. | No direct tests. |
 | method | RepoService.Fork | `func (s *RepoService) Fork(ctx context.Context, owner, repo, org string) (*types.Repository, error)` | Fork forks a repository. If org is non-empty, forks into that organisation. | `TestRepoService_Good_Fork` |
 | method | RepoService.GetArchive | `func (s *RepoService) GetArchive(ctx context.Context, owner, repo, archive string) ([]byte, error)` | GetArchive returns a repository archive as raw bytes. | `TestRepoService_GetArchive_Good` |
+| method | RepoService.GetSigningKey | `func (s *RepoService) GetSigningKey(ctx context.Context, owner, repo string) (string, error)` | GetSigningKey returns the repository signing key as ASCII-armoured text. | `TestRepoService_GetSigningKey_Good` |
 | method | RepoService.GetNewPinAllowed | `func (s *RepoService) GetNewPinAllowed(ctx context.Context, owner, repo string) (*types.NewIssuePinsAllowed, error)` | GetNewPinAllowed returns whether new issue pins are allowed for a repository. | `TestRepoService_GetNewPinAllowed_Good` |
 | method | RepoService.IterOrgRepos | `func (s *RepoService) IterOrgRepos(ctx context.Context, org string) iter.Seq2[types.Repository, error]` | IterOrgRepos returns an iterator over all repositories for an organisation. | No direct tests. |
 | method | RepoService.IterUserRepos | `func (s *RepoService) IterUserRepos(ctx context.Context) iter.Seq2[types.Repository, error]` | IterUserRepos returns an iterator over all repositories for the authenticated user. | No direct tests. |

repos.go

@@ -154,6 +154,16 @@ func (s *RepoService) GetRawFile(ctx context.Context, owner, repo, filepath stri
 	return s.client.GetRaw(ctx, path)
 }
 
+// GetSigningKey returns the repository signing key as ASCII-armoured text.
+func (s *RepoService) GetSigningKey(ctx context.Context, owner, repo string) (string, error) {
+	path := ResolvePath("/api/v1/repos/{owner}/{repo}/signing-key.gpg", pathParams("owner", owner, "repo", repo))
+	data, err := s.client.GetRaw(ctx, path)
+	if err != nil {
+		return "", err
+	}
+	return string(data), nil
+}
+
 // ListIssueTemplates returns all issue templates available for a repository.
 func (s *RepoService) ListIssueTemplates(ctx context.Context, owner, repo string) ([]types.IssueTemplate, error) {
 	path := ResolvePath("/api/v1/repos/{owner}/{repo}/issue_templates", pathParams("owner", owner, "repo", repo))

repos_test.go

@@ -426,6 +426,32 @@ func TestRepoService_ListSubscribers_Good(t *testing.T) {
 	}
 }
 
+func TestRepoService_GetSigningKey_Good(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet {
+			t.Errorf("expected GET, got %s", r.Method)
+		}
+		if r.URL.Path != "/api/v1/repos/core/go-forge/signing-key.gpg" {
+			t.Errorf("wrong path: %s", r.URL.Path)
+			http.NotFound(w, r)
+			return
+		}
+		w.Header().Set("Content-Type", "text/plain")
+		w.Write([]byte("-----BEGIN PGP PUBLIC KEY BLOCK-----\n..."))
+	}))
+	defer srv.Close()
+
+	f := NewForge(srv.URL, "tok")
+	key, err := f.Repos.GetSigningKey(context.Background(), "core", "go-forge")
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := "-----BEGIN PGP PUBLIC KEY BLOCK-----\n..."
+	if key != want {
+		t.Fatalf("got %q, want %q", key, want)
+	}
+}
+
 func TestRepoService_ListAssignees_Good(t *testing.T) {
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if r.Method != http.MethodGet {