Custom server hooks are not logged anywhere in GitLab

Summary

When server custom hook is created and the and the push happens to GitLab the custom hook message is not logged anywhere. This is an issue as there are cases when you perform a commit in the UI it would not always display the message as well, however it would still fail to commit.

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Total 6 (delta 2), reused 0 (delta 0)
remote: Hello Custom Hook

Steps to reproduce

Create a custom server hook to display a message. Push to a repository. A message displayed to the user, however, while searching through the logs it is not found anywhere in /var/log/gitlab/*

Example Project

What is the current bug behavior?

Custom server hook details should appear in the logs.

What is the expected correct behavior?

Relevant logs and/or screenshots

Output of checks

Results of GitLab environment info

Expand for output related to GitLab environment info

(For installations with omnibus-gitlab package run and paste the output of:
`sudo gitlab-rake gitlab:env:info`)

System information
System:		Ubuntu 16.04
Proxy:		no
Current User:	git
Using RVM:	no
Ruby Version:	2.6.6p146
Gem Version:	2.7.10
Bundler Version:1.17.3
Rake Version:	12.3.3
Redis Version:	5.0.9
Git Version:	2.27.0
Sidekiq Version:5.2.9
Go Version:	unknown

GitLab information
Version:	13.2.4-ee
Revision:	5f3e8be35c3
Directory:	/opt/gitlab/embedded/service/gitlab-rails
DB Adapter:	PostgreSQL
DB Version:	11.7
URL:		https://railsbit.com
HTTP Clone URL:	https://railsbit.com/some-group/some-project.git
SSH Clone URL:	git@railsbit.com:some-group/some-project.git
Elasticsearch:	no
Geo:		no
Using LDAP:	no
Using Omniauth:	yes
Omniauth Providers: 

GitLab Shell
Version:	13.3.0
Repository storage paths:
- default: 	/var/opt/gitlab/git-data/repositories
GitLab Shell path:		/opt/gitlab/embedded/service/gitlab-shell
Git:		/opt/gitlab/embedded/bin/git
(For installations from source run and paste the output of:
`sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production`)

Results of GitLab application Check

Expand for output related to the GitLab application check

(For installations with omnibus-gitlab package run and paste the output of:
`sudo gitlab-rake gitlab:check SANITIZE=true`)

Checking GitLab subtasks ...

Checking GitLab Shell ...

GitLab Shell: ... GitLab Shell version >= 13.3.0 ? ... OK (13.3.0)
Running /opt/gitlab/embedded/service/gitlab-shell/bin/check
Internal API available: OK
Redis available via internal API: OK
gitlab-shell self-check successful

Checking GitLab Shell ... Finished

Checking Gitaly ...

Gitaly: ... default ... OK

Checking Gitaly ... Finished

Checking Sidekiq ...

Sidekiq: ... Running? ... yes
Number of Sidekiq processes ... 1

Checking Sidekiq ... Finished

Checking Incoming Email ...

Incoming Email: ... Reply by email is disabled in config/gitlab.yml

Checking Incoming Email ... Finished

Checking LDAP ...

LDAP: ... LDAP is disabled in config/gitlab.yml

Checking LDAP ... Finished

Checking GitLab App ...

Git configured correctly? ... yes
Database config exists? ... yes
All migrations up? ... yes
Database contains orphaned GroupMembers? ... no
GitLab config exists? ... yes
GitLab config up to date? ... yes
Log directory writable? ... yes
Tmp directory writable? ... yes
Uploads directory exists? ... yes
Uploads directory has correct permissions? ... yes
Uploads directory tmp has correct permissions? ... yes
Init script exists? ... skipped (omnibus-gitlab has no init script)
Init script up-to-date? ... skipped (omnibus-gitlab has no init script)
Projects have namespace: ... 
2/1631 ... yes
3/1632 ... yes
28/1633 ... yes
33/1634 ... yes
10/1635 ... yes
11/1636 ... yes
28/1637 ... yes
14/1638 ... yes
29/1639 ... yes
38/1640 ... yes
18/1641 ... yes
30/1642 ... yes
37/1643 ... yes
22/1644 ... yes
23/1645 ... yes
31/1646 ... yes
27/1647 ... yes
38/1648 ... yes
30/1649 ... yes
20/1650 ... yes
17/1651 ... yes
10/1652 ... yes
31/1653 ... yes
20/1654 ... yes
22/1655 ... yes
10/1656 ... yes
14/1657 ... yes
12/1658 ... yes
9/1659 ... yes
4/1660 ... yes
8/1661 ... yes
23/1662 ... yes
11/1663 ... yes
6/1664 ... yes
17/1665 ... yes
5/1666 ... yes
40/1667 ... yes
41/1668 ... yes
40/1669 ... yes
40/1670 ... yes
40/1672 ... yes
40/1673 ... yes
40/1676 ... yes
40/1677 ... yes
40/1687 ... yes
40/1688 ... yes
40/1689 ... yes
40/1690 ... yes
40/1691 ... yes
49/1692 ... yes
40/1693 ... yes
40/1694 ... yes
52/1695 ... yes
51/1696 ... yes
40/1698 ... yes
40/1699 ... yes
40/1700 ... yes
57/1701 ... yes
52/1702 ... yes
40/1703 ... yes
40/1704 ... yes
58/1705 ... yes
40/1706 ... yes
40/1707 ... yes
40/1708 ... yes
40/1709 ... yes
40/1710 ... yes
Redis version >= 4.0.0? ... yes
Ruby version >= 2.5.3 ? ... yes (2.6.6)
Git version >= 2.22.0 ? ... yes (2.27.0)
Git user has default SSH configuration? ... yes
Active users: ... 30
Is authorized keys file accessible? ... yes
GitLab configured to store new projects in hashed storage? ... yes
All projects are in hashed storage? ... no
  Try fixing it:
  Please migrate all projects to hashed storage
  as legacy storage is deprecated in 13.0 and support will be removed in 14.0.
  For more information see:
  doc/administration/repository_storage_types.md
Elasticsearch version 6.x - 7.x? ... skipped (elasticsearch is disabled)

Checking GitLab App ... Finished


Checking GitLab subtasks ... Finished

(For installations from source run and paste the output of:
`sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true`)

(we will only investigate if the tests are passing)

Possible fixes