feat: improving apply requirements for mergeable on Gitlab (#1675)

* Improving apply requirements for mergeable on Gitlab

* Fixing end of line

* Renaming variables

* Renaming variables

* Fixing variable assignment

* Fixing variable assignment

runatlantis.io/docs/apply-requirements.md

@@ -107,12 +107,11 @@ a pull request mergeable.
 :::
 
 #### GitLab
-For GitLab, a merge request will be mergeable if it has no conflicts and if all
-required approvers have approved the pull request.
+For GitLab, a merge request will be merged if there are no conflicts, no unresolved discussions if it is a project requirement and if all necessary approvers have approved the pull request.
 
-We **do not** check if there are [Unresolved Discussions](https://docs.gitlab.com/ee/user/discussions/#resolve-a-thread) because GitLab doesn't
-provide that information in their API response. If you need this feature please
-[open an issue](https://github.com/runatlantis/atlantis/issues/new).
+For pipelines, if the project requires that pipelines must succeed, all builds except the apply command status will be checked.
+
+For Jobs with allow_failure setting set to true, will be ignored. If the pipeline has been skipped and the project allows merging, it will be marked as mergeable.
 
 #### Bitbucket.org (Bitbucket Cloud) and Bitbucket Server (Stash)
 For Bitbucket, we just check if there is a conflict that is preventing a

server/events/vcs/gitlab_client.go

@@ -14,11 +14,13 @@
 package vcs
 
 import (
+	"context"
 	"fmt"
 	"net"
 	"net/http"
 	"net/url"
 	"strings"
+	"time"
 
 	"github.com/runatlantis/atlantis/server/events/yaml"
 
@@ -167,11 +169,9 @@ func (g *GitlabClient) PullIsApproved(repo models.Repo, pull models.PullRequest)
 // PullIsMergeable returns true if the merge request can be merged.
 // In GitLab, there isn't a single field that tells us if the pull request is
 // mergeable so for now we check the merge_status and approvals_before_merge
-// fields. We aren't checking if there are unresolved discussions or failing
-// pipelines because those only block merges if the repo is set to require that.
+// fields.
 // In order to check if the repo required these, we'd need to make another API
-// call to get the repo settings. For now I'm going to leave this as is and if
-// some users require checking this as well then we can revisit.
+// call to get the repo settings.
 // It's also possible that GitLab implements their own "mergeable" field in
 // their API in the future.
 // See:
@@ -182,7 +182,33 @@ func (g *GitlabClient) PullIsMergeable(repo models.Repo, pull models.PullRequest
 	if err != nil {
 		return false, err
 	}
-	if mr.MergeStatus == "can_be_merged" && mr.ApprovalsBeforeMerge <= 0 {
+
+	// Get project configuration
+	project, _, err := g.Client.Projects.GetProject(mr.ProjectID, nil)
+	if err != nil {
+		return false, err
+	}
+
+	// Get Commit Statuses
+	statuses, _, err := g.Client.Commits.GetCommitStatuses(mr.ProjectID, mr.HeadPipeline.SHA, nil)
+	if err != nil {
+		return false, err
+	}
+
+	for _, status := range statuses {
+		if !strings.HasSuffix(status.Name, fmt.Sprintf("/%s", models.ApplyCommand.String())) {
+			if !status.AllowFailure && project.OnlyAllowMergeIfPipelineSucceeds && status.Status != "success" {
+				return false, nil
+			}
+		}
+	}
+
+	isPipelineSkipped := mr.HeadPipeline.Status == "skipped"
+	allowSkippedPipeline := project.AllowMergeOnSkippedPipeline && isPipelineSkipped
+	if mr.MergeStatus == "can_be_merged" &&
+		mr.ApprovalsBeforeMerge <= 0 &&
+		mr.BlockingDiscussionsResolved &&
+		(allowSkippedPipeline || !isPipelineSkipped) {
 		return true, nil
 	}
 	return false, nil
@@ -213,10 +239,48 @@ func (g *GitlabClient) GetMergeRequest(repoFullName string, pullNum int) (*gitla
 	return mr, err
 }
 
+func (g *GitlabClient) WaitForSuccessPipeline(ctx context.Context, pull models.PullRequest) {
+	ctx, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+
+	for wait := true; wait; {
+		select {
+		case <-ctx.Done():
+			// validation check time out
+			cancel()
+			return //ctx.Err()
+
+		default:
+			mr, _ := g.GetMergeRequest(pull.BaseRepo.FullName, pull.Num)
+			// check if pipeline has a success state to merge
+			if mr.HeadPipeline.Status == "success" {
+				return
+			}
+			time.Sleep(time.Second)
+		}
+	}
+}
+
 // MergePull merges the merge request.
 func (g *GitlabClient) MergePull(pull models.PullRequest, pullOptions models.PullRequestOptions) error {
 	commitMsg := common.AutomergeCommitMsg
-	_, _, err := g.Client.MergeRequests.AcceptMergeRequest(
+
+	mr, err := g.GetMergeRequest(pull.BaseRepo.FullName, pull.Num)
+	if err != nil {
+		return errors.Wrap(
+			err, "unable to merge merge request, it was not possible to retrieve the merge request")
+	}
+	project, _, err := g.Client.Projects.GetProject(mr.ProjectID, nil)
+	if err != nil {
+		return errors.Wrap(
+			err, "unable to merge merge request, it was not possible to check the project requirements")
+	}
+
+	if project != nil && project.OnlyAllowMergeIfPipelineSucceeds {
+		g.WaitForSuccessPipeline(context.Background(), pull)
+	}
+
+	_, _, err = g.Client.MergeRequests.AcceptMergeRequest(
 		pull.BaseRepo.FullName,
 		pull.Num,
 		&gitlab.AcceptMergeRequestOptions{

server/events/vcs/gitlab_client_test.go

@@ -141,6 +141,12 @@ func TestGitlabClient_MergePull(t *testing.T) {
 					case "/api/v4/projects/runatlantis%2Fatlantis/merge_requests/1/merge":
 						w.WriteHeader(c.code)
 						w.Write([]byte(c.glResponse)) // nolint: errcheck
+					case "/api/v4/projects/runatlantis%2Fatlantis/merge_requests/1":
+						w.WriteHeader(http.StatusOK)
+						w.Write([]byte(pipelineSuccess)) // nolint: errcheck
+					case "/api/v4/projects/4580910":
+						w.WriteHeader(http.StatusOK)
+						w.Write([]byte(projectSuccess)) // nolint: errcheck
 					case "/api/v4/":
 						// Rate limiter requests.
 						w.WriteHeader(http.StatusOK)
@@ -254,3 +260,5 @@ func TestGitlabClient_MarkdownPullLink(t *testing.T) {
 }
 
 var mergeSuccess = `{"id":22461274,"iid":13,"project_id":4580910,"title":"Update main.tf","description":"","state":"merged","created_at":"2019-01-15T18:27:29.375Z","updated_at":"2019-01-25T17:28:01.437Z","merged_by":{"id":1755902,"name":"Luke Kysow","username":"lkysow","state":"active","avatar_url":"https://secure.gravatar.com/avatar/25fd57e71590fe28736624ff24d41c5f?s=80\u0026d=identicon","web_url":"https://gitlab.com/lkysow"},"merged_at":"2019-01-25T17:28:01.459Z","closed_by":null,"closed_at":null,"target_branch":"patch-1","source_branch":"patch-1-merger","upvotes":0,"downvotes":0,"author":{"id":1755902,"name":"Luke Kysow","username":"lkysow","state":"active","avatar_url":"https://secure.gravatar.com/avatar/25fd57e71590fe28736624ff24d41c5f?s=80\u0026d=identicon","web_url":"https://gitlab.com/lkysow"},"assignee":null,"source_project_id":4580910,"target_project_id":4580910,"labels":[],"work_in_progress":false,"milestone":null,"merge_when_pipeline_succeeds":false,"merge_status":"can_be_merged","sha":"cb86d70f464632bdfbe1bb9bc0f2f9d847a774a0","merge_commit_sha":"c9b336f1c71d3e64810b8cfa2abcfab232d6bff6","user_notes_count":0,"discussion_locked":null,"should_remove_source_branch":null,"force_remove_source_branch":false,"web_url":"https://gitlab.com/lkysow/atlantis-example/merge_requests/13","time_stats":{"time_estimate":0,"total_time_spent":0,"human_time_estimate":null,"human_total_time_spent":null},"squash":false,"subscribed":true,"changes_count":"1","latest_build_started_at":null,"latest_build_finished_at":null,"first_deployed_to_production_at":null,"pipeline":null,"diff_refs":{"base_sha":"67cb91d3f6198189f433c045154a885784ba6977","head_sha":"cb86d70f464632bdfbe1bb9bc0f2f9d847a774a0","start_sha":"67cb91d3f6198189f433c045154a885784ba6977"},"merge_error":null,"approvals_before_merge":null}`
+var pipelineSuccess = `{"id": 22461274,"iid": 13,"project_id": 4580910,"title": "Update main.tf","description": "","state": "opened","created_at": "2019-01-15T18:27:29.375Z","updated_at": "2019-01-25T17:28:01.437Z","merged_by": null,"merged_at": null,"closed_by": null,"closed_at": null,"target_branch": "patch-1","source_branch": "patch-1-merger","user_notes_count": 0,"upvotes": 0,"downvotes": 0,"author": {"id": 1755902,"name": "Luke Kysow","username": "lkysow","state": "active","avatar_url": "https://secure.gravatar.com/avatar/25fd57e71590fe28736624ff24d41c5f?s=80\u0026d=identicon","web_url": "https://gitlab.com/lkysow"},"assignee": null,"reviewers": [],"source_project_id": 4580910,"target_project_id": 4580910,"labels": [],"work_in_progress": false,"milestone": null,"merge_when_pipeline_succeeds": false,"merge_status": "can_be_merged","sha": "cb86d70f464632bdfbe1bb9bc0f2f9d847a774a0","merge_commit_sha": null,"squash_commit_sha": null,"discussion_locked": null,"should_remove_source_branch": null,"force_remove_source_branch": true,"reference": "!13","references": {"short": "!13","relative": "!13","full": "lkysow/atlantis-example!13"},"web_url": "https://gitlab.com/lkysow/atlantis-example/merge_requests/13","time_stats": {"time_estimate": 0,"total_time_spent": 0,"human_time_estimate": null,"human_total_time_spent": null},"squash": true,"task_completion_status": {"count": 0,"completed_count": 0},"has_conflicts": false,"blocking_discussions_resolved": true,"approvals_before_merge": null,"subscribed": false,"changes_count": "1","latest_build_started_at": "2019-01-15T18:27:29.375Z","latest_build_finished_at": "2019-01-25T17:28:01.437Z","first_deployed_to_production_at": null,"pipeline": {"id": 488598,"sha": "67cb91d3f6198189f433c045154a885784ba6977","ref": "patch-1-merger","status": "success","created_at": "2019-01-15T18:27:29.375Z","updated_at": "2019-01-25T17:28:01.437Z","web_url": "https://gitlab.com/lkysow/atlantis-example/-/pipelines/488598"},"head_pipeline": {"id": 488598,"sha": "67cb91d3f6198189f433c045154a885784ba6977","ref": "patch-1-merger","status": "success","created_at": "2019-01-15T18:27:29.375Z","updated_at": "2019-01-25T17:28:01.437Z","web_url": "https://gitlab.com/lkysow/atlantis-example/-/pipelines/488598","before_sha": "0000000000000000000000000000000000000000","tag": false,"yaml_errors": null,"user": {"id": 1755902,"name": "Luke Kysow","username": "lkysow","state": "active","avatar_url": "https://secure.gravatar.com/avatar/25fd57e71590fe28736624ff24d41c5f?s=80\u0026d=identicon","web_url": "https://gitlab.com/lkysow"},"started_at": "2019-01-15T18:27:29.375Z","finished_at": "2019-01-25T17:28:01.437Z","committed_at": null,"duration": 31,"coverage": null,"detailed_status": {"icon": "status_success","text": "passed","label": "passed","group": "success","tooltip": "passed","has_details": true,"details_path": "/lkysow/atlantis-example/-/pipelines/488598","illustration": null,"favicon": "/assets/ci_favicons/favicon_status_success-8451333011eee8ce9f2ab25dc487fe24a8758c694827a582f17f42b0a90446a2.png"}},"diff_refs": {"base_sha": "67cb91d3f6198189f433c045154a885784ba6977","head_sha": "cb86d70f464632bdfbe1bb9bc0f2f9d847a774a0","start_sha": "67cb91d3f6198189f433c045154a885784ba6977"},"merge_error": null,"first_contribution": false,"user": {"can_merge": true}}`
+var projectSuccess = `{"id": 4580910,"description": "","name": "atlantis-example","name_with_namespace": "lkysow / atlantis-example","path": "atlantis-example","path_with_namespace": "lkysow/atlantis-example","created_at": "2018-04-30T13:44:28.367Z","default_branch": "patch-1","tag_list": [],"ssh_url_to_repo": "[email protected]:lkysow/atlantis-example.git","http_url_to_repo": "https://gitlab.com/lkysow/atlantis-example.git","web_url": "https://gitlab.com/lkysow/atlantis-example","readme_url": "https://gitlab.com/lkysow/atlantis-example/-/blob/main/README.md","avatar_url": "https://gitlab.com/uploads/-/system/project/avatar/4580910/avatar.png","forks_count": 0,"star_count": 7,"last_activity_at": "2021-06-29T21:10:43.968Z","namespace": {"id": 1,"name": "lkysow","path": "lkysow","kind": "group","full_path": "lkysow","parent_id": 1,"avatar_url": "/uploads/-/system/group/avatar/1651/platform.png","web_url": "https://gitlab.com/groups/lkysow"},"_links": {"self": "https://gitlab.com/api/v4/projects/4580910","issues": "https://gitlab.com/api/v4/projects/4580910/issues","merge_requests": "https://gitlab.com/api/v4/projects/4580910/merge_requests","repo_branches": "https://gitlab.com/api/v4/projects/4580910/repository/branches","labels": "https://gitlab.com/api/v4/projects/4580910/labels","events": "https://gitlab.com/api/v4/projects/4580910/events","members": "https://gitlab.com/api/v4/projects/4580910/members"},"packages_enabled": false,"empty_repo": false,"archived": false,"visibility": "private","resolve_outdated_diff_discussions": false,"container_registry_enabled": false,"container_expiration_policy": {"cadence": "1d","enabled": false,"keep_n": 10,"older_than": "90d","name_regex": ".*","name_regex_keep": null,"next_run_at": "2021-05-01T13:44:28.397Z"},"issues_enabled": true,"merge_requests_enabled": true,"wiki_enabled": false,"jobs_enabled": true,"snippets_enabled": true,"service_desk_enabled": false,"service_desk_address": null,"can_create_merge_request_in": true,"issues_access_level": "private","repository_access_level": "enabled","merge_requests_access_level": "enabled","forking_access_level": "enabled","wiki_access_level": "disabled","builds_access_level": "enabled","snippets_access_level": "enabled","pages_access_level": "private","operations_access_level": "disabled","analytics_access_level": "enabled","emails_disabled": null,"shared_runners_enabled": true,"lfs_enabled": false,"creator_id": 818,"import_status": "none","import_error": null,"open_issues_count": 0,"runners_token": "1234456","ci_default_git_depth": 50,"ci_forward_deployment_enabled": true,"public_jobs": true,"build_git_strategy": "fetch","build_timeout": 3600,"auto_cancel_pending_pipelines": "enabled","build_coverage_regex": null,"ci_config_path": "","shared_with_groups": [],"only_allow_merge_if_pipeline_succeeds": false,"allow_merge_on_skipped_pipeline": false,"restrict_user_defined_variables": false,"request_access_enabled": true,"only_allow_merge_if_all_discussions_are_resolved": true,"remove_source_branch_after_merge": true,"printing_merge_request_link_enabled": true,"merge_method": "merge","suggestion_commit_message": "","auto_devops_enabled": false,"auto_devops_deploy_strategy": "continuous","autoclose_referenced_issues": true,"repository_storage": "default","approvals_before_merge": 0,"mirror": false,"external_authorization_classification_label": null,"marked_for_deletion_at": null,"marked_for_deletion_on": null,"requirements_enabled": false,"compliance_frameworks": [],"permissions": {"project_access": null,"group_access": {"access_level": 50,"notification_level": 3}}}`