Merge branch 'slack_wiki_notifications' into 'master'

add slack notifications for wiki pages

## What does this MR do?

Lets the Slack service be configured to send notifications when wiki pages are created or edited.

## Are there points in the code the reviewer needs to double check?

I'm just starting to get familiar with the Gitlab codebase and I was unsure on how to get the wiki page url to pass it to the slack message, on whether or not I needed to refactor the create/update methods for wiki pages from the controller to a service (but seemed necessary to test it better), and if I needed to add a column to the web hooks table or if the services table would have been enough. Please let me know if I should change anything and I will improve the MR, thanks for checking :)

## Why was this MR needed?

Related to #563 and fixes #4233.



See merge request !2998

1 files changed, 6 insertions, 0 deletions

diff --git a/lib/gitlab/url_builder.rb b/lib/gitlab/url_builder.rb
index f1943222edf..2bbbd3074e8 100644
--- a/lib/gitlab/url_builder.rb
+++ b/lib/gitlab/url_builder.rb
@@ -20,6 +20,8 @@ module Gitlab
         merge_request_url(object)
       when Note
         note_url
+      when WikiPage
+        wiki_page_url
       else
         raise NotImplementedError.new("No URL builder defined for #{object.class}")
       end
@@ -58,5 +60,9 @@ module Gitlab
         project_snippet_url(snippet, anchor: dom_id(object))
       end
     end
+
+    def wiki_page_url
+      "#{Gitlab.config.gitlab.url}#{object.wiki.wiki_base_path}/#{object.slug}"
+    end
   end
 end