Web IDE not working with relative URL configuration

Summary

Web IDE does not work with GitLab configured to use a relative URL due to wrong API usage.

Steps to reproduce

• Configure GitLab to be accessible with a relative URL, e.g. https://server/gitlab
• Open Web IDE for any project

What is the current bug behavior?

GitLab reports the following error to the user:

Error while loading the project data. Please try again.

What is the expected correct behavior?

Web IDE should start up as with a non-relative URL configuration.

Relevant logs and/or screenshots

JavaScript console shows the following error in Chrome:

xhr.js:178 GET https://server/gitlab/api/v4/projects/gitlab%2Ftest-group%2Ftest-roject 404 ()
project.js:21 Uncaught (in promise) Error: Project not loaded gitlab/test-group/test-project
    at project.js:21

Obviously the API request should be https://server/gitlab/api/v4/projects/test-group%2Ftest-roject without the additional gitlab%2F.

Output of checks

Results of GitLab environment info

Expand for output related to GitLab environment info

System information
System:		Debian 9.4
Current User:	git
Using RVM:	no
Ruby Version:	2.3.6p384
Gem Version:	2.6.13
Bundler Version:1.13.7
Rake Version:	12.3.0
Redis Version:	3.2.11
Git Version:	2.14.3
Sidekiq Version:5.0.5
Go Version:	go1.7.4 linux/amd64
GitLab information
Version:	10.7.0
Revision:	1890d6e
Directory:	/opt/gitlab/embedded/service/gitlab-rails
DB Adapter:	postgresql
URL:		https://server/gitlab
HTTP Clone URL:	https://server/gitlab/some-group/some-project.git
SSH Clone URL:	git@server:some-group/some-project.git
Using LDAP:	no
Using Omniauth:	yes
Omniauth Providers: redmine
GitLab Shell
Version:	7.1.2
Repository storage paths:

• default: /var/opt/gitlab/git-data/repositories Hooks: /opt/gitlab/embedded/service/gitlab-shell/hooks Git: /opt/gitlab/embedded/bin/git

Results of GitLab application Check

Expand for output related to the GitLab application check

Checking GitLab Shell ...
GitLab Shell version >= 7.1.2 ? ... OK (7.1.2)
Repo base directory exists?
default... yes
Repo storage directories are symlinks?
default... no
Repo paths owned by git:root, or git:git?
default... yes
Repo paths access is drwxrws---?
default... yes
hooks directories in repos are links: ...
2/2 ... ok
2/3 ... ok
7/12 ... ok
7/13 ... ok
7/15 ... ok
7/16 ... ok
12/18 ... ok
12/20 ... ok
7/22 ... ok
7/23 ... ok
13/25 ... ok
12/28 ... ok
13/35 ... ok
2/36 ... ok
12/38 ... ok
7/42 ... ok
13/43 ... ok
13/44 ... ok
27/46 ... ok
27/47 ... ok
27/48 ... ok
27/49 ... ok
27/50 ... ok
25/51 ... ok
25/52 ... ok
25/53 ... ok
25/54 ... ok
25/55 ... ok
25/56 ... ok
25/57 ... ok
12/58 ... ok
12/59 ... ok
12/61 ... ok
12/62 ... ok
13/63 ... ok
13/67 ... ok
26/68 ... ok
12/69 ... ok
2/72 ... ok
26/73 ... ok
6/74 ... ok
13/76 ... ok
12/77 ... ok
2/90 ... ok
12/91 ... ok
2/92 ... ok
26/93 ... ok
26/94 ... ok
6/95 ... ok
13/96 ... ok
13/97 ... ok
13/98 ... ok
12/101 ... ok
2/102 ... ok
12/103 ... ok
21/104 ... ok
7/105 ... ok
12/106 ... ok
19/107 ... ok
2/108 ... ok
6/113 ... ok
12/114 ... ok
26/115 ... ok
26/116 ... ok
33/118 ... ok
33/119 ... ok
33/120 ... ok
33/121 ... ok
33/122 ... ok
13/123 ... ok
12/124 ... ok
6/125 ... ok
33/126 ... ok
2/127 ... ok
26/128 ... ok
26/129 ... ok
38/130 ... ok
39/131 ... ok
7/132 ... ok
40/133 ... ok
41/135 ... ok
20/137 ... ok
41/138 ... ok
41/139 ... ok
41/140 ... ok
41/141 ... ok
20/142 ... ok
20/143 ... ok
41/144 ... ok
41/145 ... ok
Running /opt/gitlab/embedded/service/gitlab-shell/bin/check
Check GitLab API access: OK
Redis available via internal API: OK
Access to /var/opt/gitlab/.ssh/authorized_keys: OK
gitlab-shell self-check successful
Checking GitLab Shell ... Finished
Checking Sidekiq ...
Running? ... yes
Number of Sidekiq processes ... 1
Checking Sidekiq ... Finished
Reply by email is disabled in config/gitlab.yml
Checking LDAP ...
LDAP is disabled in config/gitlab.yml
Checking LDAP ... Finished
Checking GitLab ...
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: ...
2/2 ... yes
2/3 ... yes
7/12 ... yes
7/13 ... yes
7/15 ... yes
7/16 ... yes
12/18 ... yes
12/20 ... yes
7/22 ... yes
7/23 ... yes
13/25 ... yes
12/28 ... yes
13/35 ... yes
2/36 ... yes
12/38 ... yes
7/42 ... yes
13/43 ... yes
13/44 ... yes
27/46 ... yes
27/47 ... yes
27/48 ... yes
27/49 ... yes
27/50 ... yes
25/51 ... yes
25/52 ... yes
25/53 ... yes
25/54 ... yes
25/55 ... yes
25/56 ... yes
25/57 ... yes
12/58 ... yes
12/59 ... yes
12/61 ... yes
12/62 ... yes
13/63 ... yes
13/67 ... yes
26/68 ... yes
12/69 ... yes
2/72 ... yes
26/73 ... yes
6/74 ... yes
13/76 ... yes
12/77 ... yes
2/90 ... yes
12/91 ... yes
2/92 ... yes
26/93 ... yes
26/94 ... yes
6/95 ... yes
13/96 ... yes
13/97 ... yes
13/98 ... yes
12/101 ... yes
2/102 ... yes
12/103 ... yes
21/104 ... yes
7/105 ... yes
12/106 ... yes
19/107 ... yes
2/108 ... yes
6/113 ... yes
12/114 ... yes
26/115 ... yes
26/116 ... yes
33/118 ... yes
33/119 ... yes
33/120 ... yes
33/121 ... yes
33/122 ... yes
13/123 ... yes
12/124 ... yes
6/125 ... yes
33/126 ... yes
2/127 ... yes
26/128 ... yes
26/129 ... yes
38/130 ... yes
39/131 ... yes
7/132 ... yes
40/133 ... yes
41/135 ... yes
20/137 ... yes
41/138 ... yes
41/139 ... yes
41/140 ... yes
41/141 ... yes
20/142 ... yes
20/143 ... yes
41/144 ... yes
41/145 ... yes
Redis version >= 2.8.0? ... yes
Ruby version >= 2.3.5 ? ... yes (2.3.6)
Git version >= 2.9.5 ? ... yes (2.14.3)
Git user has default SSH configuration? ... yes
Active users: ... 16
Checking GitLab ... Finished