Merge branch '36549-circuit-breaker-handles-missing-storages' into 'master'

Allow the git circuit breaker to correctly handle missing repository storages

Closes #36549

See merge request gitlab-org/gitlab-ce!14417

3 files changed, 97 insertions, 11 deletions

diff --git a/spec/lib/gitlab/git/storage/circuit_breaker_spec.rb b/spec/lib/gitlab/git/storage/circuit_breaker_spec.rb
index c86353abb7c..98cf7966dad 100644
--- a/spec/lib/gitlab/git/storage/circuit_breaker_spec.rb
+++ b/spec/lib/gitlab/git/storage/circuit_breaker_spec.rb
@@ -2,7 +2,7 @@ require 'spec_helper'
 
 describe Gitlab::Git::Storage::CircuitBreaker, clean_gitlab_redis_shared_state: true, broken_storage: true do
   let(:storage_name) { 'default' }
-  let(:circuit_breaker) { described_class.new(storage_name) }
+  let(:circuit_breaker) { described_class.new(storage_name, hostname) }
   let(:hostname) { Gitlab::Environment.hostname }
   let(:cache_key) { "storage_accessible:#{storage_name}:#{hostname}" }
 
@@ -22,7 +22,8 @@ describe Gitlab::Git::Storage::CircuitBreaker, clean_gitlab_redis_shared_state:
                             'failure_wait_time' => 30,
                             'failure_reset_time' => 1800,
                             'storage_timeout' => 5
-                          }
+                          },
+                          'nopath' => { 'path' => nil }
                          )
   end
 
@@ -59,6 +60,14 @@ describe Gitlab::Git::Storage::CircuitBreaker, clean_gitlab_redis_shared_state:
       expect(breaker).to be_a(described_class)
       expect(described_class.for_storage('default')).to eq(breaker)
     end
+
+    it 'returns a broken circuit breaker for an unknown storage' do
+      expect(described_class.for_storage('unknown').circuit_broken?).to be_truthy
+    end
+
+    it 'returns a broken circuit breaker when the path is not set' do
+      expect(described_class.for_storage('nopath').circuit_broken?).to be_truthy
+    end
   end
 
   describe '#initialize' do
diff --git a/spec/lib/gitlab/git/storage/null_circuit_breaker_spec.rb b/spec/lib/gitlab/git/storage/null_circuit_breaker_spec.rb
new file mode 100644
index 00000000000..0e645008c88
--- /dev/null
+++ b/spec/lib/gitlab/git/storage/null_circuit_breaker_spec.rb
@@ -0,0 +1,77 @@
+require 'spec_helper'
+
+describe Gitlab::Git::Storage::NullCircuitBreaker do
+  let(:storage) { 'default' }
+  let(:hostname) { 'localhost' }
+  let(:error) { nil }
+
+  subject(:breaker) { described_class.new(storage, hostname, error: error) }
+
+  context 'with an error' do
+    let(:error) { Gitlab::Git::Storage::Misconfiguration.new('error') }
+
+    describe '#perform' do
+      it { expect { breaker.perform { 'ok' } }.to raise_error(error) }
+    end
+
+    describe '#circuit_broken?' do
+      it { expect(breaker.circuit_broken?).to be_truthy }
+    end
+
+    describe '#last_failure' do
+      it { Timecop.freeze { expect(breaker.last_failure).to eq(Time.now) } }
+    end
+
+    describe '#failure_count' do
+      it { expect(breaker.failure_count).to eq(breaker.failure_count_threshold) }
+    end
+
+    describe '#failure_info' do
+      it { Timecop.freeze { expect(breaker.failure_info).to eq(Gitlab::Git::Storage::CircuitBreaker::FailureInfo.new(Time.now, breaker.failure_count_threshold)) } }
+    end
+  end
+
+  context 'not broken' do
+    describe '#perform' do
+      it { expect(breaker.perform { 'ok' }).to eq('ok') }
+    end
+
+    describe '#circuit_broken?' do
+      it { expect(breaker.circuit_broken?).to be_falsy }
+    end
+
+    describe '#last_failure' do
+      it { expect(breaker.last_failure).to be_nil }
+    end
+
+    describe '#failure_count' do
+      it { expect(breaker.failure_count).to eq(0) }
+    end
+
+    describe '#failure_info' do
+      it { expect(breaker.failure_info).to eq(Gitlab::Git::Storage::CircuitBreaker::FailureInfo.new(nil, 0)) }
+    end
+  end
+
+  describe '#failure_count_threshold' do
+    it { expect(breaker.failure_count_threshold).to eq(1) }
+  end
+
+  it 'implements the CircuitBreaker interface' do
+    ours = described_class.public_instance_methods
+    theirs = Gitlab::Git::Storage::CircuitBreaker.public_instance_methods
+
+    # These methods are not part of the public API, but are public to allow the
+    # CircuitBreaker specs to operate. They should be made private over time.
+    exceptions = %i[
+      cache_key
+      check_storage_accessible!
+      no_failures?
+      storage_available?
+      track_storage_accessible
+      track_storage_inaccessible
+    ]
+
+    expect(theirs - ours).to contain_exactly(*exceptions)
+  end
+end
diff --git a/spec/lib/gitlab/health_checks/fs_shards_check_spec.rb b/spec/lib/gitlab/health_checks/fs_shards_check_spec.rb
index f5c9680bf59..73dd236a5c6 100644
--- a/spec/lib/gitlab/health_checks/fs_shards_check_spec.rb
+++ b/spec/lib/gitlab/health_checks/fs_shards_check_spec.rb
@@ -21,7 +21,7 @@ describe Gitlab::HealthChecks::FsShardsCheck do
 
   let(:metric_class) { Gitlab::HealthChecks::Metric }
   let(:result_class) { Gitlab::HealthChecks::Result }
-  let(:repository_storages) { [:default] }
+  let(:repository_storages) { ['default'] }
   let(:tmp_dir) { Dir.mktmpdir }
 
   let(:storages_paths) do
@@ -64,7 +64,7 @@ describe Gitlab::HealthChecks::FsShardsCheck do
           allow(described_class).to receive(:storage_circuitbreaker_test) { true }
         end
 
-        it { is_expected.to include(result_class.new(false, 'cannot stat storage', shard: :default)) }
+        it { is_expected.to include(result_class.new(false, 'cannot stat storage', shard: 'default')) }
       end
 
       context 'storage points to directory that has both read and write rights' do
@@ -72,7 +72,7 @@ describe Gitlab::HealthChecks::FsShardsCheck do
           FileUtils.chmod_R(0755, tmp_dir)
         end
 
-        it { is_expected.to include(result_class.new(true, nil, shard: :default)) }
+        it { is_expected.to include(result_class.new(true, nil, shard: 'default')) }
 
         it 'cleans up files used for testing' do
           expect(described_class).to receive(:storage_write_test).with(any_args).and_call_original
@@ -85,7 +85,7 @@ describe Gitlab::HealthChecks::FsShardsCheck do
             allow(described_class).to receive(:storage_read_test).with(any_args).and_return(false)
           end
 
-          it { is_expected.to include(result_class.new(false, 'cannot read from storage', shard: :default)) }
+          it { is_expected.to include(result_class.new(false, 'cannot read from storage', shard: 'default')) }
         end
 
         context 'write test fails' do
@@ -93,7 +93,7 @@ describe Gitlab::HealthChecks::FsShardsCheck do
             allow(described_class).to receive(:storage_write_test).with(any_args).and_return(false)
           end
 
-          it { is_expected.to include(result_class.new(false, 'cannot write to storage', shard: :default)) }
+          it { is_expected.to include(result_class.new(false, 'cannot write to storage', shard: 'default')) }
         end
       end
     end
@@ -109,7 +109,7 @@ describe Gitlab::HealthChecks::FsShardsCheck do
         it 'provides metrics' do
           metrics = described_class.metrics
 
-          expect(metrics).to all(have_attributes(labels: { shard: :default }))
+          expect(metrics).to all(have_attributes(labels: { shard: 'default' }))
           expect(metrics).to include(an_object_having_attributes(name: :filesystem_accessible, value: 0))
           expect(metrics).to include(an_object_having_attributes(name: :filesystem_readable, value: 0))
           expect(metrics).to include(an_object_having_attributes(name: :filesystem_writable, value: 0))
@@ -128,7 +128,7 @@ describe Gitlab::HealthChecks::FsShardsCheck do
         it 'provides metrics' do
           metrics = described_class.metrics
 
-          expect(metrics).to all(have_attributes(labels: { shard: :default }))
+          expect(metrics).to all(have_attributes(labels: { shard: 'default' }))
           expect(metrics).to include(an_object_having_attributes(name: :filesystem_accessible, value: 1))
           expect(metrics).to include(an_object_having_attributes(name: :filesystem_readable, value: 1))
           expect(metrics).to include(an_object_having_attributes(name: :filesystem_writable, value: 1))
@@ -156,14 +156,14 @@ describe Gitlab::HealthChecks::FsShardsCheck do
     describe '#readiness' do
       subject { described_class.readiness }
 
-      it { is_expected.to include(result_class.new(false, 'cannot stat storage', shard: :default)) }
+      it { is_expected.to include(result_class.new(false, 'cannot stat storage', shard: 'default')) }
     end
 
     describe '#metrics' do
       it 'provides metrics' do
         metrics = described_class.metrics
 
-        expect(metrics).to all(have_attributes(labels: { shard: :default }))
+        expect(metrics).to all(have_attributes(labels: { shard: 'default' }))
         expect(metrics).to include(an_object_having_attributes(name: :filesystem_accessible, value: 0))
         expect(metrics).to include(an_object_having_attributes(name: :filesystem_readable, value: 0))
         expect(metrics).to include(an_object_having_attributes(name: :filesystem_writable, value: 0))