Fix not being able to block a subdomain of an already-blocked domain through the API

app/controllers/api/v1/admin/domain_blocks_controller.rb

@@ -29,10 +29,11 @@ def show
  def create
  authorize :domain_block, :create?
 
+ @domain_block = DomainBlock.new(resource_params)
  existing_domain_block = resource_params[:domain].present? ? DomainBlock.rule_for(resource_params[:domain]) : nil
- return render json: existing_domain_block, serializer: REST::Admin::ExistingDomainBlockErrorSerializer, status: 422 if existing_domain_block.present?
+ return render json: existing_domain_block, serializer: REST::Admin::ExistingDomainBlockErrorSerializer, status: 422 if conflicts_with_existing_block?(@domain_block, existing_domain_block)
 
- @domain_block = DomainBlock.create!(resource_params)
+ @domain_block.save!
  DomainBlockWorker.perform_async(@domain_block.id)
  log_action :create, @domain_block
  render json: @domain_block, serializer: REST::Admin::DomainBlockSerializer
@@ -55,6 +56,10 @@ def destroy
 
  private
 
+ def conflicts_with_existing_block?(domain_block, existing_domain_block)
+ existing_domain_block.present? && (existing_domain_block.domain == TagManager.instance.normalize_domain(domain_block.domain) || !domain_block.stricter_than?(existing_domain_block))
+ end
+
  def set_domain_blocks
  @domain_blocks = filtered_domain_blocks.order(id: :desc).to_a_paginated_by_id(limit_param(LIMIT), params_slice(:max_id, :since_id, :min_id))
  end

spec/requests/api/v1/admin/domain_blocks_spec.rb

@@ -130,7 +130,7 @@
  it_behaves_like 'forbidden for wrong role', ''
  it_behaves_like 'forbidden for wrong role', 'Moderator'
 
- it 'returns expected domain name and severity', :aggregate_failures do
+ it 'creates a domain block with the expected domain name and severity', :aggregate_failures do
  subject
 
  body = body_as_json
@@ -146,7 +146,44 @@
  expect(DomainBlock.find_by(domain: 'foo.bar.com')).to be_present
  end
 
- context 'when a stricter domain block already exists' do
+ context 'when a looser domain block already exists on a higher level domain' do
+ let(:params) { { domain: 'foo.bar.com', severity: :suspend } }
+
+ before do
+ Fabricate(:domain_block, domain: 'bar.com', severity: :silence)
+ end
+
+ it 'creates a domain block with the expected domain name and severity', :aggregate_failures do
+ subject
+
+ body = body_as_json
+
+ expect(response).to have_http_status(200)
+ expect(body).to match a_hash_including(
+ {
+ domain: 'foo.bar.com',
+ severity: 'suspend',
+ }
+ )
+
+ expect(DomainBlock.find_by(domain: 'foo.bar.com')).to be_present
+ end
+ end
+
+ context 'when a domain block already exists on the same domain' do
+ before do
+ Fabricate(:domain_block, domain: 'foo.bar.com', severity: :silence)
+ end
+
+ it 'returns existing domain block in error', :aggregate_failures do
+ subject
+
+ expect(response).to have_http_status(422)
+ expect(body_as_json[:existing_domain_block][:domain]).to eq('foo.bar.com')
+ end
+ end
+
+ context 'when a stricter domain block already exists on a higher level domain' do
  before do
  Fabricate(:domain_block, domain: 'bar.com', severity: :suspend)
  end