Add support for migrating from Gitlab (#9084)

* First stab at a Gitlab migrations interface.

* Modify JS to show migration for Gitlab

* Properly strip out #gitlab tag from repo name

* Working Gitlab migrations!
Still need to figure out how to hide tokens/etc from showing up in opts.CloneAddr

* Try #2 at trying to hide credentials.
CloneAddr was being used as OriginalURL.
Now passing OriginalURL through from the form and saving it.

* Add go-gitlab dependency

* Vendor go-gitlab

* Use gitlab.BasicAuthClient
Correct CloneURL.
This should be functioning!
Previous commits fixed "Migrated from"
from including the migration credentials.

* Replaced repoPath with repoID globally.
RepoID is grabbed in NewGitlabDownloader

* Logging touchup

* Properly set private repo status.
Properly set milestone deadline time.
Consistently use Gitlab username for 'Name'.

* Add go-gitlab vendor cache

* Fix PR migrations:
- Count of issues is kept to set a non-conflicting PR.ID
- Bool is used to tell whether to fetch Issue or PR comments

* Ensure merged PRs are closed and set with the proper time

* Remove copyright and some commented code

* Rip out '#gitlab' based self-hosted Gitlab support

* Hide given credentials for migrated repos.

CloneAddr was being saved as OriginalURL.

Now passing OriginalURL through from the form and
saving it in it's place

* Use asset.URL directly, no point in parsing.
Opened PRs should fall through to false.

* Fix importing Milestones.
Allow importing using Personal Tokens or anonymous access.

* Fix Gitlab Milestone migration if DueDate isn't set

* Empty Milestone due dates properly return nil, not zero time

* Add GITLAB_READ_TOKEN to drone unit-test step

* Add working gitlab_test.go.
A Personal Access Token, given in env variable GITLAB_READ_TOKEN
is required to run the test.

* Fix linting issues

* Add modified JS files

* Remove pre-build JS files

* Only merged PRs are marged as merged/closed

* Test topics

* Skip test if gitlab is inaccessible

* Grab personal token from username, not password.
Matches Github migration implementation

* Add SetContext() to GitlabDownloader.

* Checking Updated field in Issues.

* Actually fetch Issue Updated time from Gitlab

* Add Gitlab migration GetReviews() stub

* Fix Patch and Clone URLs

* check Updated too

* fix mod

* make vendor with go1.14

Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Lauris BH <lauris@nix.lv>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

vendor/github.com/xanzy/go-gitlab/version.go

@@ -0,0 +1,56 @@
+//
+// Copyright 2017, Andrea Funto'
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package gitlab
+
+// VersionService handles communication with the GitLab server instance to
+// retrieve its version information via the GitLab API.
+//
+// GitLab API docs: https://docs.gitlab.com/ce/api/version.md
+type VersionService struct {
+	client *Client
+}
+
+// Version represents a GitLab instance version.
+//
+// GitLab API docs: https://docs.gitlab.com/ce/api/version.md
+type Version struct {
+	Version  string `json:"version"`
+	Revision string `json:"revision"`
+}
+
+func (s Version) String() string {
+	return Stringify(s)
+}
+
+// GetVersion gets a GitLab server instance version; it is only available to
+// authenticated users.
+//
+// GitLab API docs: https://docs.gitlab.com/ce/api/version.md
+func (s *VersionService) GetVersion() (*Version, *Response, error) {
+	req, err := s.client.NewRequest("GET", "version", nil, nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	v := new(Version)
+	resp, err := s.client.Do(req, v)
+	if err != nil {
+		return nil, resp, err
+	}
+
+	return v, resp, err
+}