Integrations development guidelines

This page provides development guidelines for implementing GitLab integrations, which are part of our main Rails project.

Also see our direction page for an overview of our strategy around integrations.

This guide is a work in progress. You're welcome to ping @gitlab-org/manage/integrations if you need clarification or spot any outdated information.

Add a new integration

Define the integration

  1. Add a new model in app/models/integrations extending from Integration.

    • For example, Integrations::FooBar in app/models/integrations/foo_bar.rb.
    • For certain types of integrations, you can also build on these base classes:
      • Integrations::BaseChatNotification
      • Integrations::BaseCi
      • Integrations::BaseIssueTracker
      • Integrations::BaseMonitoring
      • Integrations::BaseSlashCommands
      • Integrations::BaseThirdPartyWiki
    • For integrations that primarily trigger HTTP calls to external services, you can also use the Integrations::HasWebHook concern. This reuses the webhook functionality in GitLab through an associated ServiceHook model, and automatically records request logs which can be viewed in the integration settings.
  2. Add the integration's underscored name ('foo_bar') to Integration::INTEGRATION_NAMES.

  3. Add the integration as an association on Project:

    has_one :foo_bar_integration, class_name: 'Integrations::FooBar'

Define properties

Integrations can define arbitrary properties to store their configuration with the class method Integration.prop_accessor. The values are stored as an encrypted JSON hash in the integrations.encrypted_properties column.

For example:

module Integrations
  class FooBar < Integration
    prop_accessor :url
    prop_accessor :tags
  end
end

Integration.prop_accessor installs accessor methods on the class. Here we would have #url, #url= and #url_changed?, to manage the url field. Fields stored in Integration#properties should be accessed by these accessors directly on the model, just like other ActiveRecord attributes.

You should always access the properties through their getters, and not interact with the properties hash directly. You must not write to the properties hash, you must use the generated setter method instead. Direct writes to this hash are not persisted.

You should also define validations for all your properties.

Also refer to the section Customize the frontend form below to see how these properties are exposed in the frontend form for the integration.

There is an alternative approach using Integration.data_field, which you may see in other integrations. With data fields the values are stored in a separate table per integration. At the moment we don't recommend using this for new integrations.

Define trigger events

Integrations are triggered by calling their #execute method in response to events in GitLab, which gets passed a payload hash with details about the event.

The supported events have some overlap with webhook events, and receive the same payload. You can specify the events you're interested in by overriding the class method Integration.supported_events in your model.

The following events are supported for integrations:

Event type Default Value Trigger
Alert event alert A a new, unique alert is recorded.
Commit event commit A commit is created or updated.
Deployment event deployment A deployment starts or finishes.
Issue event issue An issue is created, updated, or closed.
Confidential issue event confidential_issue A confidential issue is created, updated, or closed.
Job event job
Merge request event merge_request A merge request is created, updated, or merged.
Comment event comment A new comment is added.
Confidential comment event confidential_note A new comment on a confidential issue is added.
Pipeline event pipeline A pipeline status changes.
Push event push A push is made to the repository.
Tag push event tag_push New tags are pushed to the repository.
Vulnerability event (ULTIMATE) vulnerability A new, unique vulnerability is recorded.
Wiki page event wiki_page A wiki page is created or updated.

Event examples

This example defines an integration that responds to commit and merge_request events:

module Integrations
  class FooBar < Integration
    def self.supported_events
      %w[commit merge_request]
    end
  end
end

An integration can also not respond to events, and implement custom functionality some other way:

module Integrations
  class FooBar < Integration
    def self.supported_events
      []
    end
  end
end

Define configuration test

Optionally, you can define a configuration test of an integration's settings. The test is executed from the integration form's Test button, and results are returned to the user.

A good configuration test:

  • Does not change data on the service. For example, it should not trigger a CI build. Sending a message is okay.
  • Is meaningful and as thorough as possible.

If it's not possible to follow the above guidelines, consider not adding a configuration test.

To add a configuration test, define a #test method for the integration model.

The method receives data, which is a test push event payload. It should return a hash, containing the keys:

  • success (required): a boolean to indicate if the configuration test has passed.
  • result (optional): a message returned to the user if the configuration test has failed.

For example:

module Integrations
  class FooBar < Integration
    def test(data)
      success = test_api_key(data)

      { success: success, result: 'API key is invalid' }
    end
  end
end

Customize the frontend form

The frontend form is generated dynamically based on metadata defined in the model.

By default, the integration form provides:

  • A checkbox to enable or disable the integration.
  • Checkboxes for each of the trigger events returned from Integration#configurable_events.

You can also add help text at the top of the form by either overriding Integration#help, or providing a template in app/views/shared/integrations/$INTEGRATION_NAME/_help.html.haml.

To add your custom properties to the form, you can define the metadata for them in Integration#fields.

This method should return an array of hashes for each field, where the keys can be:

Key Type Required Default Description
type: string true The type of the form field. Can be text, textarea, password, checkbox, or select.
name: string true The property name for the form field. This must match a prop_accessor defined on the class.
required: boolean false false Specify if the form field is required or optional.
title: string false Capitalized value of name: The label for the form field.
placeholder: string false A placeholder for the form field.
help: string false A help text that displays below the form field.
api_only: boolean false false Specify if the field should only be available through the API, and excluded from the frontend form.

Additional keys for type: 'checkbox'

Key Type Required Default Description
checkbox_label: string false Value of title: A custom label that displays next to the checkbox.

Additional keys for type: 'select'

Key Type Required Default Description
choices: array true A nested array of [label, value] tuples.

Additional keys for type: 'password'

Key Type Required Default Description
non_empty_password_title: string false Value of title: An alternative label that displays when a value is already stored.
non_empty_password_help: string false Value of help: An alternative help text that displays when a value is already stored.

Frontend form examples

This example defines a required url field, and optional username and password fields:

module Integrations
  class FooBar < Integration
    prop_accessor :url, :username, :password

    def fields
      [
        {
          type: 'text',
          name: 'url',
          title: s_('FooBarIntegration|Server URL'),
          placeholder: 'https://example.com/',
          required: true
        },
        {
          type: 'text',
          name: 'username',
          title: s_('FooBarIntegration|Username'),
        },
        {
          type: 'password',
          name: 'password',
          title: s_('FoobarIntegration|Password'
          non_empty_password_title: s_('FooBarIntegration|Enter new password')
        }
      ]
    end
  end
end

Expose the integration in the REST API

To expose the integration in the REST API:

  1. Add the integration's class (::Integrations::FooBar) to API::Helpers::IntegrationsHelpers.integration_classes.
  2. Add all properties that should be exposed to API::Helpers::IntegrationsHelpers.integrations.
  3. Update the reference documentation in doc/api/integrations.md, add a new section for your integration, and document all properties.

You can also refer to our REST API style guide.

Sensitive fields are not exposed over the API. Sensitive fields are those fields that contain any of the following in their name:

  • key
  • passphrase
  • password
  • secret
  • token
  • webhook

Availability of integrations

By default, integrations are available on the project, group, and instance level. Most integrations only act in a project context, but can be still configured from the group and instance levels.

For some integrations it can make sense to only make it available on the project level. To do that, the integration must be removed from Integration::INTEGRATION_NAMES and added to Integration::PROJECT_SPECIFIC_INTEGRATION_NAMES instead.

When developing a new integration, we also recommend you gate the availability behind a feature flag in Integration.available_integration_names.

Documentation

You can provide help text in the integration form, including links to off-site documentation, as described above in Customize the frontend form. Refer to our usability guidelines for help text.

For more detailed documentation, provide a page in doc/user/project/integrations, and link it from the Integrations overview.

You can also refer to our general documentation guidelines.

Testing

Testing should not be confused with defining configuration tests.

It is often sufficient to add tests for the integration model in spec/models/integrations, and a factory with example settings in spec/factories/integrations.rb.

Each integration is also tested as part of generalized tests. For example, there are feature specs that verify that the settings form is rendering correctly for all integrations.

If your integration implements any custom behavior, especially in the frontend, this should be covered by additional tests.

You can also refer to our general testing guidelines.

Internationalization

All UI strings should be prepared for translation by following our internationalization guidelines.

The strings should use the integration name as namespace, for example, s_('FooBarIntegration|My string').

Ongoing migrations and refactorings

Developers should be aware that the Integrations team is in the process of unifying the way integration properties are defined.

Integration examples

You can refer to these issues for examples of adding new integrations:

  • Datadog: Metrics collector, similar to the Prometheus integration.
  • EWM/RTC: External issue tracker.
  • Shimo: External wiki, similar to the Confluence and External Wiki integrations.
  • Webex Teams: Chat notifications.
  • ZenTao: External issue tracker with custom issue views, similar to the Jira integration.