Fix timeout error when loading pipelines by commit SHA for GraphQL

It was loading all the pipelines for a given project and tried to match
them from with the requested one from Ruby. This was causing database
statement timeouts for projects with lots of pipelines.

app/graphql/resolvers/project_pipeline_resolver.rb

@@ -31,7 +31,7 @@ module Resolvers
         end
       else
         BatchLoader::GraphQL.for(sha).batch(key: project) do |shas, loader, args|
-          finder = ::Ci::PipelinesFinder.new(project, current_user, shas: shas)
+          finder = ::Ci::PipelinesFinder.new(project, current_user, sha: shas)
 
           finder.execute.each { |pipeline| loader.call(pipeline.sha.to_s, pipeline) }
         end

changelogs/unreleased/ci-fix-pipeline-loading-by-sha-for-graphql.yml

+---
+title: Fix loading pipelines by commit SHA for GraphQL
+merge_request:
+author:
+type: fixed

spec/graphql/resolvers/project_pipeline_resolver_spec.rb

@@ -7,6 +7,7 @@ RSpec.describe Resolvers::ProjectPipelineResolver do
 
   let_it_be(:project) { create(:project) }
   let_it_be(:pipeline) { create(:ci_pipeline, project: project, iid: '1234', sha: 'sha') }
+  let_it_be(:other_project_pipeline) { create(:ci_pipeline, project: project, iid: '1235', sha: 'sha2') }
   let_it_be(:other_pipeline) { create(:ci_pipeline) }
   let(:current_user) { create(:user) }
 
@@ -23,6 +24,11 @@ RSpec.describe Resolvers::ProjectPipelineResolver do
   end
 
   it 'resolves pipeline for the passed iid' do
+    expect(Ci::PipelinesFinder)
+      .to receive(:new)
+      .with(project, current_user, iids: ['1234'])
+      .and_call_original
+
     result = batch_sync do
       resolve_pipeline(project, { iid: '1234' })
     end
@@ -31,6 +37,11 @@ RSpec.describe Resolvers::ProjectPipelineResolver do
   end
 
   it 'resolves pipeline for the passed sha' do
+    expect(Ci::PipelinesFinder)
+      .to receive(:new)
+      .with(project, current_user, sha: ['sha'])
+      .and_call_original
+
     result = batch_sync do
       resolve_pipeline(project, { sha: 'sha' })
     end
@@ -39,8 +50,6 @@ RSpec.describe Resolvers::ProjectPipelineResolver do
   end
 
   it 'keeps the queries under the threshold for iid' do
-    create(:ci_pipeline, project: project, iid: '1235')
-
     control = ActiveRecord::QueryRecorder.new do
       batch_sync { resolve_pipeline(project, { iid: '1234' }) }
     end
@@ -54,8 +63,6 @@ RSpec.describe Resolvers::ProjectPipelineResolver do
   end
 
   it 'keeps the queries under the threshold for sha' do
-    create(:ci_pipeline, project: project, sha: 'sha2')
-
     control = ActiveRecord::QueryRecorder.new do
       batch_sync { resolve_pipeline(project, { sha: 'sha' }) }
     end