Removes validation_message from YamlProcessor

* Updated/removed specs
* Updated the validation_message method in the blob viewer for
gitlab-ci.yml to use Gitlab::Ci::Lint.new(..).validate(..)
* Until we have a new design for the UI, the blob should continue
displaying only one error.

app/models/blob_viewer/gitlab_ci_yml.rb

@@ -15,7 +15,9 @@ module BlobViewer
 
       prepare!
 
-      @validation_message = Gitlab::Ci::YamlProcessor.validation_message(blob.data, opts)
+      @validation_message = Gitlab::Ci::Lint
+        .new(project: opts[:project], current_user: opts[:user], sha: opts[:sha])
+        .validate(blob.data).errors.first
     end
 
     def valid?(opts)

changelogs/unreleased/lm-expose-errors-linter.yml

+---
+title: 'API: Exposes errors in lint endpoint'
+merge_request: 50891
+author:
+type: changed

doc/administration/troubleshooting/gitlab_rails_cheat_sheet.md

@@ -743,7 +743,7 @@ m.project.try(:ci_service)
 ```ruby
 project = Project.find_by_full_path 'group/project'
 content = project.repository.gitlab_ci_yml_for(project.repository.root_ref_sha)
-Gitlab::Ci::YamlProcessor.validation_message(content,  user: User.first)
+Gitlab::Ci::Lint.new(project: project,  current_user: User.first).validate(content)
 ```
 
 ### Disable AutoDevOps on Existing Projects

lib/api/lint.rb

@@ -12,14 +12,13 @@ module API
       end
       post '/lint' do
         result = Gitlab::Ci::YamlProcessor.new(params[:content], user: current_user).execute
-        error = result.errors.first
 
         status 200
 
-        response = if error.blank?
+        response = if result.errors.empty?
                      { status: 'valid', errors: [], warnings: result.warnings }
                    else
-                     { status: 'invalid', errors: [error], warnings: result.warnings }
+                     { status: 'invalid', errors: result.errors, warnings: result.warnings }
                    end
 
         response.tap do |response|

lib/gitlab/ci/lint.rb

@@ -18,9 +18,10 @@ module Gitlab
         end
       end
 
-      def initialize(project:, current_user:)
+      def initialize(project:, current_user:, sha: nil)
         @project = project
         @current_user = current_user
+        @sha = sha || project.repository.commit.sha
       end
 
       def validate(content, dry_run: false)
@@ -51,7 +52,7 @@ module Gitlab
           content,
           project: @project,
           user: @current_user,
-          sha: @project.repository.commit.sha
+          sha: @sha
         ).execute
 
         Result.new(

lib/gitlab/ci/yaml_processor.rb

@@ -10,12 +10,6 @@ module Gitlab
     class YamlProcessor
       ValidationError = Class.new(StandardError)
 
-      def self.validation_message(content, opts = {})
-        result = new(content, opts).execute
-
-        result.errors.first
-      end
-
       def initialize(config_content, opts = {})
         @config_content = config_content
         @opts = opts

spec/lib/gitlab/ci/yaml_processor_spec.rb

@@ -2711,40 +2711,6 @@ module Gitlab
         end
       end
 
-      describe "#validation_message" do
-        subject { Gitlab::Ci::YamlProcessor.validation_message(content) }
-
-        context "when the YAML could not be parsed" do
-          let(:content) { YAML.dump("invalid: yaml: test") }
-
-          it { is_expected.to eq "Invalid configuration format" }
-        end
-
-        context "when the tags parameter is invalid" do
-          let(:content) { YAML.dump({ rspec: { script: "test", tags: "mysql" } }) }
-
-          it { is_expected.to eq "jobs:rspec:tags config should be an array of strings" }
-        end
-
-        context "when YAML content is empty" do
-          let(:content) { '' }
-
-          it { is_expected.to eq "Please provide content of .gitlab-ci.yml" }
-        end
-
-        context 'when the YAML contains an unknown alias' do
-          let(:content) { 'steps: *bad_alias' }
-
-          it { is_expected.to eq "Unknown alias: bad_alias" }
-        end
-
-        context "when the YAML is valid" do
-          let(:content) { File.read(Rails.root.join('spec/support/gitlab_stubs/gitlab_ci.yml')) }
-
-          it { is_expected.to be_nil }
-        end
-      end
-
       describe '#execute' do
         subject { Gitlab::Ci::YamlProcessor.new(content).execute }
 

spec/requests/api/lint_spec.rb

@@ -63,7 +63,7 @@ RSpec.describe API::Lint do
       end
 
       context 'with invalid configuration' do
-        let(:yaml_content) { '{ image: "ruby:2.7",  services: ["postgres"] }' }
+        let(:yaml_content) { '{ image: "ruby:2.7",  services: ["postgres"], invalid }' }
 
         it 'responds with errors about invalid configuration' do
           post api('/ci/lint'), params: { content: yaml_content }
@@ -71,7 +71,7 @@ RSpec.describe API::Lint do
           expect(response).to have_gitlab_http_status(:ok)
           expect(json_response['status']).to eq('invalid')
           expect(json_response['warnings']).to eq([])
-          expect(json_response['errors']).to eq(['jobs config should contain at least one visible job'])
+          expect(json_response['errors']).to eq(['jobs invalid config should implement a script: or a trigger: keyword', 'jobs config should contain at least one visible job'])
         end
 
         it 'outputs expanded yaml content' do