Revert "Merge branch '50070-legacy-attachments' into 'master'"

This reverts commit fd19f887dfeeeedb483c4a4fb32f9f768e89389c, reversing
changes made to abb2d4c601d796339c8d7cb0c00946696730f198.

1 files changed, 0 insertions, 82 deletions

diff --git a/doc/administration/troubleshooting/migration.md b/doc/administration/troubleshooting/migration.md
deleted file mode 100644
index 4d2d268b9df..00000000000
--- a/doc/administration/troubleshooting/migration.md
+++ /dev/null
@@ -1,82 +0,0 @@
-# Migrations problems
-
-## Legacy upload migration
-
-> Introduced in GitLab 12.0.
-
-  The migration takes all attachments uploaded by legacy `AttachmentUploader` and
-  migrate them to the path that current uploaders expect.
-
-Although it should not usually happen there could possibly be some attachments belonging to
-LegacyDiffNotes. These attachments can't be seen before running the migration by users and
-they should not be present in your instance.
-
-However, if you have some of them, you will need to handle them manually.
-You can find the ids of failed notes in logs as "MigrateLegacyUploads: LegacyDiffNote"
-
-1. Run a Rails console:
-
-    ```sh
-    sudo gitlab-rails console production
-    ```
-
-    or for source installs:
-
-    ```sh
-    bundle exec rails console production
-    ```
-
- 1. Check the failed upload and find the note (you can see their ids in the logs)
-
-    ```ruby
-    upload = Upload.find(upload_id)
-    note = Note.find(note_id)
-    ```
-
-
- 1. Check the path - it should contain `system/note/attachment`
-
-    ```ruby
-    upload.absolut_path
-    ```
-    
- 1. Check the path in the uploader - it should differ from the upload path and should contain  `system/legacy_diff_note`
- 
-    ```ruby
-    uploader = upload.build_uploader
-    uploader.file
-    ```
-    
- 1. First, you need to move the file to the path that is expected from the uploader
-
-    ```ruby
-    old_path = upload.absolute_path
-    new_path = upload.absolute_path.sub('-/system/note/attachment', '-/system/legacy_diff_note')
-    new_dir = File.dirname(new_path)
-    FileUtils.mkdir_p(new_dir)
-    
-    FileUtils.mv(old_path, new_path)
-    ```
-
- 1. You then need to move the file to the `FileUploader` and create a new `Upload` object
- 
-    ```ruby
-    file_uploader = UploadService.new(note.project, File.read(new_path)).execute
-    ```
- 
- 1. And update the legacy note to contain the file.
- 
-    ```ruby
-    new_text = "#{note.note} \n #{file_uploader.markdown_link}"
-    note.update!(
-      note: new_text
-    )
-    ```
-
- 1. And finally, you can remove the old upload
- 
-    ```ruby
-    upload.destroy
-    ```
-
-If you have any problems feel free to contact [GitLab Support](https://about.gitlab.com/support/).