Merge branch 'setter-for-key' into 'master'

Use setter for key instead AR callback

## What does this MR do?

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- n/a [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- n/a API support added
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/6763

See merge request !7488

app/models/key.rb

@@ -6,7 +6,7 @@ class Key < ActiveRecord::Base
 
   belongs_to :user
 
-  before_validation :strip_white_space, :generate_fingerprint
+  before_validation :generate_fingerprint
 
   validates :title, presence: true, length: { within: 0..255 }
   validates :key, presence: true, length: { within: 0..5000 }, format: { with: /\A(ssh|ecdsa)-.*\Z/ }
@@ -21,8 +21,9 @@ class Key < ActiveRecord::Base
   after_destroy :remove_from_shell
   after_destroy :post_destroy_hook
 
-  def strip_white_space
-    self.key = key.strip unless key.blank?
+  def key=(value)
+    value.strip! unless value.blank?
+    write_attribute(:key, value)
   end
 
   def publishable_key

changelogs/unreleased/setter-for-key.yml

+---
+title: Use setter for key instead AR callback
+merge_request: 7488
+author: Semyon Pupkov

spec/models/key_spec.rb

@@ -71,15 +71,25 @@ describe Key, models: true do
 
   context 'callbacks' do
     it 'adds new key to authorized_file' do
-      @key = build(:personal_key, id: 7)
-      expect(GitlabShellWorker).to receive(:perform_async).with(:add_key, @key.shell_id, @key.key)
-      @key.save
+      key = build(:personal_key, id: 7)
+      expect(GitlabShellWorker).to receive(:perform_async).with(:add_key, key.shell_id, key.key)
+      key.save!
     end
 
     it 'removes key from authorized_file' do
-      @key = create(:personal_key)
-      expect(GitlabShellWorker).to receive(:perform_async).with(:remove_key, @key.shell_id, @key.key)
-      @key.destroy
+      key = create(:personal_key)
+      expect(GitlabShellWorker).to receive(:perform_async).with(:remove_key, key.shell_id, key.key)
+      key.destroy
+    end
+  end
+
+  describe '#key=' do
+    let(:valid_key) do
+      "ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAIEAiPWx6WM4lhHNedGfBpPJNPpZ7yKu+dnn1SJejgt4596k6YjzGGphH2TUxwKzxcKDKKezwkpfnxPkSMkuEspGRt/aZZ9wa++Oi7Qkr8prgHc4soW6NUlfDzpvZK2H5E7eQaSeP3SAwGmQKUFHCddNaP0L+hM7zhFNzjFvpaMgJw0= dummy@gitlab.com"
+    end
+
+    it 'strips white spaces' do
+      expect(described_class.new(key: " #{valid_key} ").key).to eq(valid_key)
     end
   end
 end