--- stage: Verify group: Pipeline Authoring info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments type: reference --- # Multi-project pipelines **(FREE)** > [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/199224) to GitLab Free in 12.8. You can set up [GitLab CI/CD](README.md) across multiple projects, so that a pipeline in one project can trigger a pipeline in another project. For an overview see the [Multi-project pipelines demo](https://www.youtube.com/watch?v=g_PIwBM1J84). GitLab CI/CD is a powerful continuous integration tool that works not only per project, but also across projects with multi-project pipelines. Multi-project pipelines are useful for larger products that require cross-project inter-dependencies, such as those adopting a [microservices architecture](https://about.gitlab.com/blog/2016/08/16/trends-in-version-control-land-microservices/). Cross-functional development teams can use cross-pipeline triggering to trigger multiple pipelines for different microservices projects. Learn more in the [Cross-project Pipeline Triggering and Visualization demo](https://about.gitlab.com/learn/) at GitLab@learn, in the Continuous Integration (CI) section. Additionally, it's possible to visualize the entire pipeline, including all cross-project inter-dependencies. **(PREMIUM)** ## Use cases Let's assume you deploy your web app from different projects in GitLab: - One for the free version, which has its own pipeline that builds and tests your app - One for the paid version add-ons, which also pass through builds and tests - One for the documentation, which also builds, tests, and deploys with an SSG With Multi-Project Pipelines you can visualize the entire pipeline, including all build and test stages for the three projects. ## Multi-project pipeline visualization **(PREMIUM)** When you configure GitLab CI/CD for your project, you can visualize the stages of your [jobs](pipelines/index.md#configure-a-pipeline) on a [pipeline graph](pipelines/index.md#visualize-pipelines). ![Multi-project pipeline graph](img/multi_project_pipeline_graph.png) In the Merge Request Widget, multi-project pipeline mini-graphs are displayed, and when hovering or tapping (on touchscreen devices) they expand and are shown adjacent to each other. ![Multi-project mini graph](img/multi_pipeline_mini_graph.gif) ## Triggering multi-project pipelines through API > [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/31573) to GitLab Free in 12.4. When you use the [`CI_JOB_TOKEN` to trigger pipelines](triggers/README.md#ci-job-token), GitLab recognizes the source of the job token, and thus internally ties these pipelines together, allowing you to visualize their relationships on pipeline graphs. These relationships are displayed in the pipeline graph by showing inbound and outbound connections for upstream and downstream pipeline dependencies. When using: - CI/CD Variables or [`rules`](yaml/README.md#rulesif) to control job behavior, the value of the [`$CI_PIPELINE_SOURCE` predefined variable](variables/predefined_variables.md) is `pipeline` for multi-project pipeline triggered through the API with `CI_JOB_TOKEN`. - [`only/except`](yaml/README.md#only--except) to control job behavior, use the `pipelines` keyword. ## Creating multi-project pipelines from `.gitlab-ci.yml` > [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/199224) to GitLab Free in 12.8. ### Triggering a downstream pipeline using a bridge job Before GitLab 11.8, it was necessary to implement a pipeline job that was responsible for making the API request [to trigger a pipeline](#triggering-multi-project-pipelines-through-api) in a different project. In GitLab 11.8, GitLab provides a new CI/CD configuration syntax to make this task easier, and avoid needing GitLab Runner for triggering cross-project pipelines. The following illustrates configuring a bridge job: ```yaml rspec: stage: test script: bundle exec rspec staging: variables: ENVIRONMENT: staging stage: deploy trigger: my/deployment ``` In the example above, as soon as the `rspec` job succeeds in the `test` stage, the `staging` bridge job is started. The initial status of this job is `pending`. GitLab then creates a downstream pipeline in the `my/deployment` project and, as soon as the pipeline is created, the `staging` job succeeds. `my/deployment` is a full path to that project. The user that created the upstream pipeline needs to have access rights to the downstream project (`my/deployment` in this case). If a downstream project is not found, or a user does not have access rights to create a pipeline there, the `staging` job is marked as _failed_. When using: - CI/CD variables or [`rules`](yaml/README.md#rulesif) to control job behavior, the value of the [`$CI_PIPELINE_SOURCE` predefined variable](variables/predefined_variables.md) is `pipeline` for multi-project pipelines triggered with a bridge job (using the [`trigger:`](yaml/README.md#trigger) keyword). - [`only/except`](yaml/README.md#only--except) to control job behavior, use the `pipelines` keyword. In the example, `staging` is marked as successful as soon as a downstream pipeline gets created. If you want to display the downstream pipeline's status instead, see [Mirroring status from triggered pipeline](#mirroring-status-from-triggered-pipeline). NOTE: Bridge jobs [do not support every configuration keyword](#limitations) that can be used with other jobs. If a user tries to use unsupported configuration keywords, YAML validation fails on pipeline creation. ### Specifying a downstream pipeline branch It is possible to specify a branch name that a downstream pipeline uses: ```yaml rspec: stage: test script: bundle exec rspec staging: stage: deploy trigger: project: my/deployment branch: stable-11-2 ``` Use: - The `project` keyword to specify the full path to a downstream project. - The `branch` keyword to specify the name of a branch in the project specified by `project`. [From GitLab 12.4](https://gitlab.com/gitlab-org/gitlab/-/issues/10126), variable expansion is supported. GitLab uses a commit that is on the head of the branch when creating a downstream pipeline. NOTE: Pipelines triggered on a protected branch in a downstream project use the [permissions](../user/permissions.md) of the user that ran the trigger job in the upstream project. If the user does not have permission to run CI/CD pipelines against the protected branch, the pipeline fails. See [pipeline security for protected branches](pipelines/index.md#pipeline-security-on-protected-branches). ### Passing CI/CD variables to a downstream pipeline #### With the `variables` keyword Sometimes you might want to pass CI/CD variables to a downstream pipeline. You can do that using the `variables` keyword, just like you would when defining a regular job. ```yaml rspec: stage: test script: bundle exec rspec staging: variables: ENVIRONMENT: staging stage: deploy trigger: my/deployment ``` The `ENVIRONMENT` variable is passed to every job defined in a downstream pipeline. It is available as a variable when GitLab Runner picks a job. In the following configuration, the `MY_VARIABLE` variable is passed to the downstream pipeline that is created when the `trigger-downstream` job is queued. This is because `trigger-downstream` job inherits variables declared in global variables blocks, and then we pass these variables to a downstream pipeline. ```yaml variables: MY_VARIABLE: my-value trigger-downstream: variables: ENVIRONMENT: something trigger: my/project ``` You might want to pass some information about the upstream pipeline using, for example, predefined variables. In order to do that, you can use interpolation to pass any variable. For example: ```yaml downstream-job: variables: UPSTREAM_BRANCH: $CI_COMMIT_REF_NAME trigger: my/project ``` In this scenario, the `UPSTREAM_BRANCH` variable with a value related to the upstream pipeline is passed to the `downstream-job` job, and is available within the context of all downstream builds. Upstream pipelines take precedence over downstream ones. If there are two variables with the same name defined in both upstream and downstream projects, the ones defined in the upstream project take precedence. #### With variable inheritance You can pass variables to a downstream pipeline with [`dotenv` variable inheritance](variables/README.md#pass-an-environment-variable-to-another-job) and [cross project artifact downloads](yaml/README.md#cross-project-artifact-downloads-with-needs). In the upstream pipeline: 1. Save the variables in a `.env` file. 1. Save the `.env` file as a `dotenv` report. 1. Trigger the downstream pipeline. ```yaml build_vars: stage: build script: - echo "BUILD_VERSION=hello" >> build.env artifacts: reports: dotenv: build.env deploy: stage: deploy trigger: my/downstream_project ``` Set the `test` job in the downstream pipeline to inherit the variables from the `build_vars` job in the upstream project with `needs:`. The `test` job inherits the variables in the `dotenv` report and it can access `BUILD_VERSION` in the script: ```yaml test: stage: test script: - echo $BUILD_VERSION needs: - project: my/upstream_project job: build_vars ref: master artifacts: true ``` ### Mirroring status from triggered pipeline > - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/11238) in GitLab Premium 12.3. > - [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/199224) to GitLab Free in 12.8. You can mirror the pipeline status from the triggered pipeline to the source bridge job by using `strategy: depend`. For example: ```yaml trigger_job: trigger: project: my/project strategy: depend ``` ### Mirroring status from upstream pipeline You can mirror the pipeline status from an upstream pipeline to a bridge job by using the `needs:pipeline` keyword. The latest pipeline status from the default branch is replicated to the bridge job. Example: ```yaml upstream_bridge: stage: test needs: pipeline: other/project ``` ### Limitations Bridge jobs are a little different from regular jobs. It is not possible to use exactly the same configuration syntax as when defining regular jobs that are picked by a runner. Some features are not implemented yet. For example, support for environments. [Configuration keywords](yaml/README.md) available for bridge jobs are: - `trigger` (to define a downstream pipeline trigger) - `stage` - `allow_failure` - [`rules`](yaml/README.md#rules) - `only` and `except` - `when` (only with `on_success`, `on_failure`, and `always` values) - `extends` - `needs` ## Trigger a pipeline when an upstream project is rebuilt **(PREMIUM)** > [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/9045) in GitLab Premium 12.8. You can trigger a pipeline in your project whenever a pipeline finishes for a new tag in a different project: 1. Go to the project's **Settings > CI/CD** page, and expand the **Pipeline subscriptions** section. 1. Enter the project you want to subscribe to, in the format `/`. For example, if the project is `https://gitlab.com/gitlab-org/gitlab`, use `gitlab-org/gitlab`. 1. Click subscribe. Any pipelines that complete successfully for new tags in the subscribed project now trigger a pipeline on the current project's default branch. The maximum number of upstream pipeline subscriptions is 2 by default, for both the upstream and downstream projects. This [application limit](../administration/instance_limits.md#number-of-cicd-subscriptions-to-a-project) can be changed on self-managed instances by a GitLab administrator. The upstream project needs to be [public](../public_access/public_access.md) and the user must have [developer permissions](../user/permissions.md#project-members-permissions) for the upstream project. ## Downstream private projects confidentiality concern If you trigger a pipeline in a downstream private project, the name of the project and the status of the pipeline is visible in the upstream project's pipelines page. If you have a public project that can trigger downstream pipelines in a private project, make sure to check that there are no confidentiality problems.