<!-- The first four sections: "Problem to solve", "Intended users", "User experience goal", and "Proposal", are strongly recommended, while the rest of the sections can be filled out during the problem validation or breakdown phase. However, keep in mind that providing complete and relevant information early helps our product team validate the problem and start working on a solution. --> ### Problem to solve The CI Lint currently uses `YamlProcessor` to validate the content passed in. The `YamlProcessor` represents a small part of the whole pipeline creation process and it only covers syntax errors. Using `YamlProcessor` today it gives a false sense of validation to users because it can return that a configuration is valid but when trying to create a pipeline it fails for some other reasons not considered before. Typical examples are logical validations that occur beyond the `YamlProcessor`. Example: The following syntax is considered valid by CI Lint but it would return an error `test: needs 'build'` when trying to actually create the pipeline. ```yaml build: script: echo stage: build rules: - if: '$CI_MERGE_REQUEST_ID' test: script: echo stage: test needs: [build] ``` ### Intended users * [Devon (DevOps Engineer)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#devon-devops-engineer) ### User experience goal <!-- What is the single user experience workflow this problem addresses? For example, "The user should be able to use the UI/API/.gitlab-ci.yml with GitLab to <perform a specific task>" https://about.gitlab.com/handbook/engineering/ux/ux-research-training/user-story-mapping/ --> Improved understanding of errors at lint-time. ### Proposal <!-- How are we going to solve the problem? Try to include the user journey! https://about.gitlab.com/handbook/journeys/#user-journey --> We will introduce a new mode in `Ci::CreatePipelineService` called `dry_run: true` (which is `false` by default). This mode would skip persisting the pipeline while letting everything else happening. In the end, a non-persisted pipeline is returned including any errors and (recently added) warnings. Then we change the Lint controller to use `Ci::CreatePipelineService` with `dry_run: true` and pass in the content to validate. ### Further details <!-- Include use cases, benefits, goals, or any other details that will help us understand the problem better. --> ### Permissions and Security <!-- What permissions are required to perform the described actions? Are they consistent with the existing permissions as documented for users, groups, and projects as appropriate? Is the proposed behavior consistent between the UI, API, and other access methods (e.g. email replies)? Consider adding checkboxes and expectations of users with certain levels of membership https://docs.gitlab.com/ee/user/permissions.html * [ ] Add expected impact to members with no access (0) * [ ] Add expected impact to Guest (10) members * [ ] Add expected impact to Reporter (20) members * [ ] Add expected impact to Developer (30) members * [ ] Add expected impact to Maintainer (40) members * [ ] Add expected impact to Owner (50) members --> ### Documentation <!-- See the Feature Change Documentation Workflow https://docs.gitlab.com/ee/development/documentation/workflow.html#for-a-product-change * Add all known Documentation Requirements in this section. See https://docs.gitlab.com/ee/development/documentation/feature-change-workflow.html#documentation-requirements * If this feature requires changing permissions, update the permissions document. See https://docs.gitlab.com/ee/user/permissions.html --> ### Availability & Testing <!-- This section needs to be retained and filled in during the workflow planning breakdown phase of this feature proposal, if not earlier. What risks does this change pose to our availability? How might it affect the quality of the product? What additional test coverage or changes to tests will be needed? Will it require cross-browser testing? Please list the test areas (unit, integration and end-to-end) that needs to be added or updated to ensure that this feature will work as intended. Please use the list below as guidance. * Unit test changes * Integration test changes * End-to-end test change See the test engineering planning process and reach out to your counterpart Software Engineer in Test for assistance: https://about.gitlab.com/handbook/engineering/quality/test-engineering/#test-planning --> * Unit test changes - Yes, please add unit tests along with new/updated logics * Integration test changes - not required * End-to-end test change - not required ### What does success look like, and how can we measure that? <!-- Define both the success metrics and acceptance criteria. Note that success metrics indicate the desired business outcomes, while acceptance criteria indicate when the solution is working correctly. If there is no way to measure success, link to an issue that will implement a way to measure this. --> ### What is the type of buyer? <!-- What is the buyer persona for this feature? See https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/buyer-persona/ In which enterprise tier should this feature go? See https://about.gitlab.com/handbook/product/pricing/#four-tiers --> ### Is this a cross-stage feature? <!-- Communicate if this change will affect multiple Stage Groups or product areas. We recommend always start with the assumption that a feature request will have an impact into another Group. Loop in the most relevant PM and Product Designer from that Group to provide strategic support to help align the Group's broader plan and vision, as well as to avoid UX and technical debt. https://about.gitlab.com/handbook/product/#cross-stage-features --> ### Links / references