Add RepositoriesService.GetByID method.

Note: GetByID uses the undocumented GitHub API endpoint /repositories/:id.

Include license preview Accept header.

Helps #329.

github/repos.go

@@ -277,6 +277,29 @@ func (s *RepositoriesService) Get(owner, repo string) (*Repository, *Response, e
 	return repository, resp, err
 }
 
+// GetByID fetches a repository.
+//
+// Note: GetByID uses the undocumented GitHub API endpoint /repositories/:id.
+func (s *RepositoriesService) GetByID(id int) (*Repository, *Response, error) {
+	u := fmt.Sprintf("repositories/%d", id)
+	req, err := s.client.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// TODO: remove custom Accept header when the license support fully launches
+	// https://developer.github.com/v3/licenses/#get-a-repositorys-license
+	req.Header.Set("Accept", mediaTypeLicensesPreview)
+
+	repository := new(Repository)
+	resp, err := s.client.Do(req, repository)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return repository, resp, err
+}
+
 // Edit updates a repository.
 //
 // GitHub API docs: http://developer.github.com/v3/repos/#edit

github/repos_test.go

@@ -222,6 +222,27 @@ func TestRepositoriesService_Get(t *testing.T) {
 	}
 }
 
+func TestRepositoriesService_GetByID(t *testing.T) {
+	setup()
+	defer teardown()
+
+	mux.HandleFunc("/repositories/1", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+		testHeader(t, r, "Accept", mediaTypeLicensesPreview)
+		fmt.Fprint(w, `{"id":1,"name":"n","description":"d","owner":{"login":"l"},"license":{"key":"mit"}}`)
+	})
+
+	repo, _, err := client.Repositories.GetByID(1)
+	if err != nil {
+		t.Errorf("Repositories.GetByID returned error: %v", err)
+	}
+
+	want := &Repository{ID: Int(1), Name: String("n"), Description: String("d"), Owner: &User{Login: String("l")}, License: &License{Key: String("mit")}}
+	if !reflect.DeepEqual(repo, want) {
+		t.Errorf("Repositories.GetByID returned %+v, want %+v", repo, want)
+	}
+}
+
 func TestRepositoriesService_Edit(t *testing.T) {
 	setup()
 	defer teardown()