Guidelines for implementing Enterprise Edition features
- Write the code and the tests.: As with any code, EE features should have good test coverage to prevent regressions.
-
Write documentation.: Add documentation to the
doc/
directory. Describe the feature and include screenshots, if applicable. -
Submit a MR to the
www-gitlab-com
project.: Add the new feature to the EE features list.
Act as CE when unlicensed
Since the implementation of GitLab CE features to work with unlicensed EE instance
GitLab Enterprise Edition should work like GitLab Community Edition
when no license is active. So EE features always should be guarded by
project.feature_available?
or group.feature_available?
(or
License.feature_available?
if it is a system-wide feature).
CE specs should remain untouched as much as possible and extra specs
should be added for EE. Licensed features can be stubbed using the
spec helper stub_licensed_features
in EE::LicenseHelpers
.
Separation of EE code
We want a single code base eventually, but before we reach the goal, we still need to merge changes from GitLab CE to EE. To help us get there, we should make sure that we no longer edit CE files in place in order to implement EE features.
Instead, all EE code should be put inside the ee/
top-level directory. The
rest of the code should be as close to the CE files as possible.
EE-specific comments
When complete separation can't be achieved with the ee/
directory, you can wrap
code in EE specific comments to designate the difference from CE/EE and add
some context for someone resolving a conflict.
# EE-specific start
stub_licensed_features(variable_environment_scope: true)
# EE specific end
-# EE-specific start
= render 'ci/variables/environment_scope', form_field: form_field, variable: variable
-# EE-specific end
EE-specific comments should not be backported to CE.
Note: This is only meant as a workaround, we should follow up and resolve this soon.
Detection of EE-only files
For each commit (except on master
), the ee-files-location-check
CI job tries
to detect if there are any new files that are EE-only. If any file is detected,
the job fails with an explanation of why and what to do to make it pass.
Basically, the fix is simple: git mv <file> ee/<file>
.
How to name your branches?
For any EE branch, the job will try to detect its CE counterpart by removing any
ee-
prefix or -ee
suffix from the EE branch name, and matching the last
branch that contains it.
For instance, from the EE branch new-shiny-feature-ee
(or
ee-new-shiny-feature
), the job would find the corresponding CE branches:
new-shiny-feature
ce-new-shiny-feature
new-shiny-feature-ce
my-super-new-shiny-feature-in-ce
ee/
Whitelist some EE-only files that cannot be moved to The ee-files-location-check
CI job provides a whitelist of files or folders
that cannot or should not be moved to ee/
. Feel free to open an issue to
discuss adding a new file/folder to this whitelist.
For instance, it was decided that moving EE-only files from qa/
to ee/qa/
would make it difficult to build the gitLab-{ce,ee}-qa
Docker images and it
was not worth the complexity.
EE-only features
If the feature being developed is not present in any form in CE, we don't
need to put the codes under EE
namespace. For example, an EE model could
go into: ee/app/models/awesome.rb
using Awesome
as the class name. This
is applied not only to models. Here's a list of other examples:
ee/app/controllers/foos_controller.rb
ee/app/finders/foos_finder.rb
ee/app/helpers/foos_helper.rb
ee/app/mailers/foos_mailer.rb
ee/app/models/foo.rb
ee/app/policies/foo_policy.rb
ee/app/serializers/foo_entity.rb
ee/app/serializers/foo_serializer.rb
ee/app/services/foo/create_service.rb
ee/app/validators/foo_attr_validator.rb
ee/app/workers/foo_worker.rb
ee/app/views/foo.html.haml
ee/app/views/foo/_bar.html.haml
This works because for every path that are present in CE's eager-load/auto-load
paths, we add the same ee/
-prepended path in config/application.rb
.
This also applies to views.
EE features based on CE features
For features that build on existing CE features, write a module in the EE
namespace and prepend
it in the CE class, on the last line of the file that
the class resides in. This makes conflicts less likely to happen during CE to EE
merges because only one line is added to the CE class - the prepend
line. For
example, to prepend a module into the User
class you would use the following
approach:
class User < ActiveRecord::Base
# ... lots of code here ...
end
User.prepend(EE::User)
Since the module would require an EE
namespace, the file should also be
put in an ee/
sub-directory. For example, we want to extend the user model
in EE, so we have a module called ::EE::User
put inside
ee/app/models/ee/user.rb
.
This is also not just applied to models. Here's a list of other examples:
ee/app/controllers/ee/foos_controller.rb
ee/app/finders/ee/foos_finder.rb
ee/app/helpers/ee/foos_helper.rb
ee/app/mailers/ee/foos_mailer.rb
ee/app/models/ee/foo.rb
ee/app/policies/ee/foo_policy.rb
ee/app/serializers/ee/foo_entity.rb
ee/app/serializers/ee/foo_serializer.rb
ee/app/services/ee/foo/create_service.rb
ee/app/validators/ee/foo_attr_validator.rb
ee/app/workers/ee/foo_worker.rb
Overriding CE methods
To override a method present in the CE codebase, use prepend
. It
lets you override a method in a class with a method from a module, while
still having access the class's implementation with super
.
There are a few gotchas with it:
-
you should always
extend ::Gitlab::Utils::Override
and useoverride
to guard the "overrider" method to ensure that if the method gets renamed in CE, the EE override won't be silently forgotten. -
when the "overrider" would add a line in the middle of the CE implementation, you should refactor the CE method and split it in smaller methods. Or create a "hook" method that is empty in CE, and with the EE-specific implementation in EE.
-
when the original implementation contains a guard clause (e.g.
return unless condition
), we cannot easily extend the behaviour by overriding the method, because we can't know when the overridden method (i.e. callingsuper
in the overriding method) would want to stop early. In this case, we shouldn't just override it, but update the original method to make it call the other method we want to extend, like a template method pattern. For example, given this base:class Base def execute return unless enabled? # ... # ... end end
Instead of just overriding
Base#execute
, we should update it and extract the behaviour into another method:class Base def execute return unless enabled? do_something end private def do_something # ... # ... end end
Then we're free to override that
do_something
without worrying about the guards:module EE::Base extend ::Gitlab::Utils::Override override :do_something def do_something # Follow the above pattern to call super and extend it end end
This would require updating CE first, or make sure this is back ported to CE.
When prepending, place them in the ee/
specific sub-directory, and
wrap class or module in module EE
to avoid naming conflicts.
For example to override the CE implementation of
ApplicationController#after_sign_out_path_for
:
def after_sign_out_path_for(resource)
current_application_settings.after_sign_out_path.presence || new_user_session_path
end
Instead of modifying the method in place, you should add prepend
to
the existing file:
class ApplicationController < ActionController::Base
# ...
def after_sign_out_path_for(resource)
current_application_settings.after_sign_out_path.presence || new_user_session_path
end
# ...
end
ApplicationController.prepend(EE::ApplicationController)
And create a new file in the ee/
sub-directory with the altered
implementation:
module EE
module ApplicationController
extend ::Gitlab::Utils::Override
override :after_sign_out_path_for
def after_sign_out_path_for(resource)
if Gitlab::Geo.secondary?
Gitlab::Geo.primary_node.oauth_logout_url(@geo_logout_state)
else
super
end
end
end
end
Overriding CE class methods
The same applies to class methods, except we want to use
ActiveSupport::Concern
and put extend ::Gitlab::Utils::Override
within the block of class_methods
. Here's an example:
module EE
module Groups
module GroupMembersController
extend ActiveSupport::Concern
class_methods do
extend ::Gitlab::Utils::Override
override :admin_not_required_endpoints
def admin_not_required_endpoints
super.concat(%i[update override])
end
end
end
end
end
Use self-descriptive wrapper methods
When it's not possible/logical to modify the implementation of a method. Wrap it in a self-descriptive method and use that method.
For example, in CE only an admin
is allowed to access all private
projects/groups, but in EE also an auditor
has full private
access. It would be incorrect to override the implementation of
User#admin?
, so instead add a method full_private_access?
to
app/models/users.rb
. The implementation in CE will be:
def full_private_access?
admin?
end
In EE, the implementation ee/app/models/ee/users.rb
would be:
override :full_private_access?
def full_private_access?
super || auditor?
end
In lib/gitlab/visibility_level.rb
this method is used to return the
allowed visibility levels:
def levels_for_user(user = nil)
if user.full_private_access?
[PRIVATE, INTERNAL, PUBLIC]
elsif # ...
end
See CE MR and EE MR for full implementation details.
config/routes
Code in When we add draw :admin
in config/routes.rb
, the application will try to
load the file located in config/routes/admin.rb
, and also try to load the
file located in ee/config/routes/admin.rb
.
In EE, it should at least load one file, at most two files. If it cannot find any files, an error will be raised. In CE, since we don't know if there will be an EE route, it will not raise any errors even if it cannot find anything.
This means if we want to extend a particular CE route file, just add the same
file located in ee/config/routes
. If we want to add an EE only route, we
could still put draw :ee_only
in both CE and EE, and add
ee/config/routes/ee_only.rb
in EE, similar to render_if_exists
.
app/controllers/
Code in In controllers, the most common type of conflict is with before_action
that
has a list of actions in CE but EE adds some actions to that list.
The same problem often occurs for params.require
/ params.permit
calls.
Mitigations
Separate CE and EE actions/keywords. For instance for params.require
in
ProjectsController
:
def project_params
params.require(:project).permit(project_params_attributes)
end
# Always returns an array of symbols, created however best fits the use case.
# It _should_ be sorted alphabetically.
def project_params_attributes
%i[
description
name
path
]
end
In the EE::ProjectsController
module:
def project_params_attributes
super + project_params_attributes_ee
end
def project_params_attributes_ee
%i[
approvals_before_merge
approver_group_ids
approver_ids
...
]
end
app/models/
Code in EE-specific models should extend EE::Model
.
For example, if EE has a specific Tanuki
model, you would
place it in ee/app/models/ee/tanuki.rb
.
app/views/
Code in It's a very frequent problem that EE is adding some specific view code in a CE view. For instance the approval code in the project's settings page.
Mitigations
Blocks of code that are EE-specific should be moved to partials. This avoids conflicts with big chunks of HAML code that are not fun to resolve when you add the indentation to the equation.
EE-specific views should be placed in ee/app/views/
, using extra
sub-directories if appropriate.
render_if_exists
Using Instead of using regular render
, we should use render_if_exists
, which
will not render anything if it cannot find the specific partial. We use this
so that we could put render_if_exists
in CE, keeping code the same between
CE and EE.
The advantages of this:
- Minimal code difference between CE and EE.
- Very clear hints about where we're extending EE views while reading CE codes.
The disadvantage of this:
- Slightly more work while developing EE features, because now we need to
port
render_if_exists
to CE. - If we have typos in the partial name, it would be silently ignored.
render_ce
Using For render
and render_if_exists
, they search for the EE partial first,
and then CE partial. They would only render a particular partial, not all
partials with the same name. We could take the advantage of this, so that
the same partial path (e.g. shared/issuable/form/default_templates
) could
be referring to the CE partial in CE (i.e.
app/views/shared/issuable/form/_default_templates.html.haml
), while EE
partial in EE (i.e.
ee/app/views/shared/issuable/form/_default_templates.html.haml
). This way,
we could show different things between CE and EE.
However sometimes we would also want to reuse the CE partial in EE partial because we might just want to add something to the existing CE partial. We could workaround this by adding another partial with a different name, but it would be tedious to do so.
In this case, we could as well just use render_ce
which would ignore any EE
partials. One example would be
ee/app/views/shared/issuable/form/_default_templates.html.haml
:
- if @project.feature_available?(:issuable_default_templates)
= render_ce 'shared/issuable/form/default_templates'
- elsif show_promotions?
= render 'shared/promotions/promote_issue_templates'
In the above example, we can't use
render 'shared/issuable/form/default_templates'
because it would find the
same EE partial, causing infinite recursion. Instead, we could use render_ce
so it ignores any partials in ee/
and then it would render the CE partial
(i.e. app/views/shared/issuable/form/_default_templates.html.haml
)
for the same path (i.e. shared/issuable/form/default_templates
). This way
we could easily wrap around the CE partial.
lib/
Code in Place EE-specific logic in the top-level EE
module namespace. Namespace the
class beneath the EE
module just as you would normally.
For example, if CE has LDAP classes in lib/gitlab/ldap/
then you would place
EE-specific LDAP classes in ee/lib/ee/gitlab/ldap
.
lib/api/
Code in It can be very tricky to extend EE features by a single line of prepend
,
and for each different Grape feature,
we might need different strategies to extend it. To apply different strategies
easily, we would use extend ActiveSupport::Concern
in the EE module.
Put the EE module files following EE features based on CE features.
EE API routes
For EE API routes, we put them in a prepended
block:
module EE
module API
module MergeRequests
extend ActiveSupport::Concern
prepended do
params do
requires :id, type: String, desc: 'The ID of a project'
end
resource :projects, requirements: ::API::API::NAMESPACE_OR_PROJECT_REQUIREMENTS do
# ...
end
end
end
end
end
Note that due to namespace differences, we need to use the full qualifier for some constants.
EE params
We can define params
and utilize use
in another params
definition to
include params defined in EE. However, we need to define the "interface" first
in CE in order for EE to override it. We don't have to do this in other places
due to prepend
, but Grape is complex internally and we couldn't easily do
that, so we'll follow regular object-oriented practices that we define the
interface first here.
For example, suppose we have a few more optional params for EE, given this CE API code:
module API
class MergeRequests < Grape::API
# EE::API::MergeRequests would override the following helpers
helpers do
params :optional_params_ee do
end
end
params :optional_params do
# CE specific params go here...
use :optional_params_ee
end
end
end
API::MergeRequests.prepend(EE::API::MergeRequests)
And then we could override it in EE module:
module EE
module API
module MergeRequests
extend ActiveSupport::Concern
prepended do
helpers do
params :optional_params_ee do
# EE specific params go here...
end
end
end
end
end
end
This way, the only difference between CE and EE for that API file would be
prepend EE::API::MergeRequests
.
EE helpers
To make it easy for an EE module to override the CE helpers, we need to define those helpers we want to extend first. Try to do that immediately after the class definition to make it easy and clear:
module API
class JobArtifacts < Grape::API
# EE::API::JobArtifacts would override the following helpers
helpers do
def authorize_download_artifacts!
authorize_read_builds!
end
end
end
end
API::JobArtifacts.prepend(EE::API::JobArtifacts)
And then we can follow regular object-oriented practices to override it:
module EE
module API
module JobArtifacts
extend ActiveSupport::Concern
prepended do
helpers do
def authorize_download_artifacts!
super
check_cross_project_pipelines_feature!
end
end
end
end
end
end
EE-specific behaviour
Sometimes we need EE-specific behaviour in some of the APIs. Normally we could use EE methods to override CE methods, however API routes are not methods and therefore can't be simply overridden. We need to extract them into a standalone method, or introduce some "hooks" where we could inject behavior in the CE route. Something like this:
module API
class MergeRequests < Grape::API
helpers do
# EE::API::MergeRequests would override the following helpers
def update_merge_request_ee(merge_request)
end
end
put ':id/merge_requests/:merge_request_iid/merge' do
merge_request = find_project_merge_request(params[:merge_request_iid])
# ...
update_merge_request_ee(merge_request)
# ...
end
end
end
API::MergeRequests.prepend(EE::API::MergeRequests)
Note that update_merge_request_ee
doesn't do anything in CE, but
then we could override it in EE:
module EE
module API
module MergeRequests
extend ActiveSupport::Concern
prepended do
helpers do
def update_merge_request_ee(merge_request)
# ...
end
end
end
end
end
end
route_setting
EE It's very hard to extend this in an EE module, and this is simply storing
some meta-data for a particular route. Given that, we could simply leave the
EE route_setting
in CE as it won't hurt and we are just not going to use
those meta-data in CE.
We could revisit this policy when we're using route_setting
more and whether
or not we really need to extend it from EE. For now we're not using it much.
Utilizing class methods for setting up EE-specific data
Sometimes we need to use different arguments for a particular API route, and we
can't easily extend it with an EE module because Grape has different context in
different blocks. In order to overcome this, we need to move the data to a class
method that resides in a separate module or class. This allows us to extend that
module or class before its data is used, without having to place a prepend
in
the middle of CE code.
For example, in one place we need to pass an extra argument to
at_least_one_of
so that the API could consider an EE-only argument as the
least argument. We would approach this as follows:
# api/merge_requests/parameters.rb
module API
class MergeRequests < Grape::API
module Parameters
def self.update_params_at_least_one_of
%i[
assignee_id
description
]
end
end
end
end
API::MergeRequests::Parameters.prepend(EE::API::MergeRequests::Parameters)
# api/merge_requests.rb
module API
class MergeRequests < Grape::API
params do
at_least_one_of(*Parameters.update_params_at_least_one_of)
end
end
end
And then we could easily extend that argument in the EE class method:
module EE
module API
module MergeRequests
module Parameters
extend ActiveSupport::Concern
class_methods do
extend ::Gitlab::Utils::Override
override :update_params_at_least_one_of
def update_params_at_least_one_of
super.push(*%i[
squash
])
end
end
end
end
end
end
It could be annoying if we need this for a lot of routes, but it might be the simplest solution right now.
This approach can also be used when models define validations that depend on class methods. For example:
# app/models/identity.rb
class Identity < ActiveRecord::Base
def self.uniqueness_scope
[:provider]
end
prepend EE::Identity
validates :extern_uid,
allow_blank: true,
uniqueness: { scope: uniqueness_scope, case_sensitive: false }
end
# ee/app/models/ee/identity.rb
module EE
module Identity
extend ActiveSupport::Concern
class_methods do
extend ::Gitlab::Utils::Override
def uniqueness_scope
[*super, :saml_provider_id]
end
end
end
end
Instead of taking this approach, we would refactor our code into the following:
# ee/app/models/ee/identity/uniqueness_scopes.rb
module EE
module Identity
module UniquenessScopes
extend ActiveSupport::Concern
class_methods do
extend ::Gitlab::Utils::Override
def uniqueness_scope
[*super, :saml_provider_id]
end
end
end
end
end
# app/models/identity/uniqueness_scopes.rb
class Identity < ActiveRecord::Base
module UniquenessScopes
def self.uniqueness_scope
[:provider]
end
end
end
Identity::UniquenessScopes.prepend(EE::Identity::UniquenessScopes)
# app/models/identity.rb
class Identity < ActiveRecord::Base
validates :extern_uid,
allow_blank: true,
uniqueness: { scope: Identity::UniquenessScopes.scopes, case_sensitive: false }
end
spec/
Code in When you're testing EE-only features, avoid adding examples to the existing CE specs. Also do no change existing CE examples, since they should remain working as-is when EE is running without a license.
Instead place EE specs in the ee/spec
folder.
spec/factories
Code in Use FactoryBot.modify
to extend factories already defined in CE.
Note that you cannot define new factories (even nested ones) inside the FactoryBot.modify
block. You can do so in a
separate FactoryBot.define
block as shown in the example below:
# ee/spec/factories/notes.rb
FactoryBot.modify do
factory :note do
trait :on_epic do
noteable { create(:epic) }
project nil
end
end
end
FactoryBot.define do
factory :note_on_epic, parent: :note, traits: [:on_epic]
end
assets/javascripts/
JavaScript code in To separate EE-specific JS-files we should also move the files into an ee
folder.
For example there can be an
app/assets/javascripts/protected_branches/protected_branches_bundle.js
and an
EE counterpart
ee/app/assets/javascripts/protected_branches/protected_branches_bundle.js
.
The corresponding import statement would then look like this:
// app/assets/javascripts/protected_branches/protected_branches_bundle.js
import bundle from '~/protected_branches/protected_branches_bundle.js';
// ee/app/assets/javascripts/protected_branches/protected_branches_bundle.js
// (only works in EE)
import bundle from 'ee/protected_branches/protected_branches_bundle.js';
// in CE: app/assets/javascripts/protected_branches/protected_branches_bundle.js
// in EE: ee/app/assets/javascripts/protected_branches/protected_branches_bundle.js
import bundle from 'ee_else_ce/protected_branches/protected_branches_bundle.js';
See the frontend guide performance section for information on managing page-specific javascript within EE.
assets/javascript
Vue code in script tag
Child Component only used in EE
To seperate Vue template differences we should async import the components.
Doing this allows for us to load the correct component in EE whilst in CE we can load a empty component that renders nothing. This code should exist in the CE repository as well as the EE repository.
<script>
export default {
components: {
EEComponent: () => import('ee_component/components/test.vue'),
},
};
</script>
<template>
<div>
<ee-component />
</div>
</template>
For JS code that is EE only, like props, computed properties, methods, etc, we will keep the current approach
- Since we can't async load a mixin we will use the
ee_else_ce
alias we already have for webpack. - This means all the EE specific props, computed properties, methods, etc that are EE only should be in a mixin in the
ee/
folder and we need to create a CE counterpart of the mixin
Example:
import mixin from 'ee_else_ce/path/mixin';
{
mixins: [mixin]
}
-
Computed Properties/methods and getters only used in the child import still need a counterpart in CE
-
For store modules, we will need a CE counterpart too.
-
You can see an MR with an example here
template
tag
-
EE Child components
- Since we are using the async loading to check which component to load, we'd still use the component's name, check this example.
-
EE extra HTML
- For the templates that have extra HTML in EE we will use the
ifEE
mixin with thev-if
directive. - You can either use the
template
tag as a wrapper or directly in the element, if there is only one element to be rendered in EE:
- For the templates that have extra HTML in EE we will use the
<template v-if="ifEE">
<p>Several</p>
<p>non wrapper</p>
<p>elements</p>
<p>that are rendered</p>
<p>in EE only</p>
</template>
<ul v-if="renderIfEE">
<li>One wrapped</li>
<li>element</li>
<li>that is rendered</li>
<li>in EE only</li>
</template>
Non Vue Files
For regular JS files, the approach is similar.
- We will keep using the
ee_else_ce
helper, this means that EE only code should be inside theee/
folder. - An EE file should be created with the EE only code, and it should extend the CE counterpart.
- For code inside functions that can't be extended, we will use an
if
statement with theifEE
helper
Example:
import { ifEE } from '~/lib/utils/common_utils'
if (renderIfEE) {
$('.js-import-git-toggle-button').on('click', () => {
const $projectMirror = $('#project_mirror');
$projectMirror.attr('disabled', !$projectMirror.attr('disabled'));
});
}
assets/stylesheets
SCSS code in To separate EE-specific styles in SCSS files, if a component you're adding styles for
is limited to only EE, it is better to have a separate SCSS file in appropriate directory
within app/assets/stylesheets
.
See backporting changes for instructions on how to merge changes safely.
In some cases, this is not entirely possible or creating dedicated SCSS file is an overkill, e.g. a text style of some component is different for EE. In such cases, styles are usually kept in stylesheet that is common for both CE and EE, and it is wise to isolate such ruleset from rest of CE rules (along with adding comment describing the same) to avoid conflicts during CE to EE merge.
Bad
.section-body {
.section-title {
background: $gl-header-color;
}
&.ee-section-body {
.section-title {
background: $gl-header-color-cyan;
}
}
}
Good
.section-body {
.section-title {
background: $gl-header-color;
}
}
// EE-specific start
.section-body.ee-section-body {
.section-title {
background: $gl-header-color-cyan;
}
}
// EE-specific end
Backporting changes from EE to CE
When working in EE-specific features, you might have to tweak a few files that are not EE-specific. Here is a workflow to make sure those changes end up backported safely into CE too. (This approach does not refer to changes introduced via csslab.)
- Make your changes in the EE branch. If possible, keep a separated commit (to be squashed) to help backporting and review.
- Open merge request to EE project.
-
Apply the changes you made to CE files in a branch of the CE project. (Tip: Use
patch
with the diff from your commit in EE branch) - Open merge request to CE project, referring it's a backport of EE changes and link to MR open in EE.
- Once EE MR is merged, the MR towards CE can be merged. But not before.
Note: regarding SCSS, make sure the files living outside /ee/
don't diverge between CE and EE projects.
gitlab-svgs
Conflicts in app/assets/images/icons.json
or app/assets/images/icons.svg
can
be resolved simply by regenerating those assets with
yarn run svg
.