debian-mirror-gitlab/lib/gitlab/gitaly_client.rb
2019-07-31 17:26:46 +00:00

449 lines
14 KiB
Ruby

# frozen_string_literal: true
require 'base64'
require 'gitaly'
require 'grpc/health/v1/health_pb'
require 'grpc/health/v1/health_services_pb'
module Gitlab
module GitalyClient
include Gitlab::Metrics::Methods
class TooManyInvocationsError < StandardError
attr_reader :call_site, :invocation_count, :max_call_stack
def initialize(call_site, invocation_count, max_call_stack, most_invoked_stack)
@call_site = call_site
@invocation_count = invocation_count
@max_call_stack = max_call_stack
stacks = most_invoked_stack.join('\n') if most_invoked_stack
msg = "GitalyClient##{call_site} called #{invocation_count} times from single request. Potential n+1?"
msg = "#{msg}\nThe following call site called into Gitaly #{max_call_stack} times:\n#{stacks}\n" if stacks
super(msg)
end
end
PEM_REGEX = /\-+BEGIN CERTIFICATE\-+.+?\-+END CERTIFICATE\-+/m.freeze
SERVER_VERSION_FILE = 'GITALY_SERVER_VERSION'
MAXIMUM_GITALY_CALLS = 30
CLIENT_NAME = (Sidekiq.server? ? 'gitlab-sidekiq' : 'gitlab-web').freeze
SERVER_FEATURE_CATFILE_CACHE = 'catfile-cache'.freeze
# Server feature flags should use '_' to separate words.
SERVER_FEATURE_FLAGS = [SERVER_FEATURE_CATFILE_CACHE, 'delta_islands'].freeze
MUTEX = Mutex.new
define_histogram :gitaly_controller_action_duration_seconds do
docstring "Gitaly endpoint histogram by controller and action combination"
base_labels Gitlab::Metrics::Transaction::BASE_LABELS.merge(gitaly_service: nil, rpc: nil)
end
def self.stub(name, storage)
MUTEX.synchronize do
@stubs ||= {}
@stubs[storage] ||= {}
@stubs[storage][name] ||= begin
klass = stub_class(name)
addr = stub_address(storage)
creds = stub_creds(storage)
klass.new(addr, creds, interceptors: interceptors)
end
end
end
def self.interceptors
return [] unless Labkit::Tracing.enabled?
[Labkit::Tracing::GRPCInterceptor.instance]
end
private_class_method :interceptors
def self.stub_cert_paths
cert_paths = Dir["#{OpenSSL::X509::DEFAULT_CERT_DIR}/*"]
cert_paths << OpenSSL::X509::DEFAULT_CERT_FILE if File.exist? OpenSSL::X509::DEFAULT_CERT_FILE
cert_paths
end
def self.stub_certs
return @certs if @certs
@certs = stub_cert_paths.flat_map do |cert_file|
File.read(cert_file).scan(PEM_REGEX).map do |cert|
OpenSSL::X509::Certificate.new(cert).to_pem
rescue OpenSSL::OpenSSLError => e
Rails.logger.error "Could not load certificate #{cert_file} #{e}"
Gitlab::Sentry.track_exception(e, extra: { cert_file: cert_file })
nil
end.compact
end.uniq.join("\n")
end
def self.stub_creds(storage)
if URI(address(storage)).scheme == 'tls'
GRPC::Core::ChannelCredentials.new stub_certs
else
:this_channel_is_insecure
end
end
def self.stub_class(name)
if name == :health_check
Grpc::Health::V1::Health::Stub
else
Gitaly.const_get(name.to_s.camelcase.to_sym).const_get(:Stub)
end
end
def self.stub_address(storage)
address(storage).sub(%r{^tcp://|^tls://}, '')
end
def self.clear_stubs!
MUTEX.synchronize do
@stubs = nil
end
end
def self.random_storage
Gitlab.config.repositories.storages.keys.sample
end
def self.address(storage)
params = Gitlab.config.repositories.storages[storage]
raise "storage not found: #{storage.inspect}" if params.nil?
address = params['gitaly_address']
unless address.present?
raise "storage #{storage.inspect} is missing a gitaly_address"
end
unless URI(address).scheme.in?(%w(tcp unix tls))
raise "Unsupported Gitaly address: #{address.inspect} does not use URL scheme 'tcp' or 'unix' or 'tls'"
end
address
end
def self.address_metadata(storage)
Base64.strict_encode64(JSON.dump(storage => connection_data(storage)))
end
def self.connection_data(storage)
{ 'address' => address(storage), 'token' => token(storage) }
end
# All Gitaly RPC call sites should use GitalyClient.call. This method
# makes sure that per-request authentication headers are set.
#
# This method optionally takes a block which receives the keyword
# arguments hash 'kwargs' that will be passed to gRPC. This allows the
# caller to modify or augment the keyword arguments. The block must
# return a hash.
#
# For example:
#
# GitalyClient.call(storage, service, rpc, request) do |kwargs|
# kwargs.merge(deadline: Time.now + 10)
# end
#
def self.call(storage, service, rpc, request, remote_storage: nil, timeout: nil)
start = Gitlab::Metrics::System.monotonic_time
request_hash = request.is_a?(Google::Protobuf::MessageExts) ? request.to_h : {}
enforce_gitaly_request_limits(:call)
kwargs = request_kwargs(storage, timeout, remote_storage: remote_storage)
kwargs = yield(kwargs) if block_given?
stub(service, storage).__send__(rpc, request, kwargs) # rubocop:disable GitlabSecurity/PublicSend
ensure
duration = Gitlab::Metrics::System.monotonic_time - start
# Keep track, separately, for the performance bar
self.query_time += duration
gitaly_controller_action_duration_seconds.observe(
current_transaction_labels.merge(gitaly_service: service.to_s, rpc: rpc.to_s),
duration)
if peek_enabled?
add_call_details(feature: "#{service}##{rpc}", duration: duration, request: request_hash, rpc: rpc,
backtrace: Gitlab::Profiler.clean_backtrace(caller))
end
end
def self.query_time
SafeRequestStore[:gitaly_query_time] ||= 0
end
def self.query_time=(duration)
SafeRequestStore[:gitaly_query_time] = duration
end
def self.query_time_ms
(self.query_time * 1000).round(2)
end
def self.current_transaction_labels
Gitlab::Metrics::Transaction.current&.labels || {}
end
private_class_method :current_transaction_labels
# For some time related tasks we can't rely on `Time.now` since it will be
# affected by Timecop in some tests, and the clock of some gitaly-related
# components (grpc's c-core and gitaly server) use system time instead of
# timecop's time, so tests will fail.
# `Time.at(Process.clock_gettime(Process::CLOCK_REALTIME))` will circumvent
# timecop.
def self.real_time
Time.at(Process.clock_gettime(Process::CLOCK_REALTIME))
end
private_class_method :real_time
def self.authorization_token(storage)
token = token(storage).to_s
issued_at = real_time.to_i.to_s
hmac = OpenSSL::HMAC.hexdigest(OpenSSL::Digest::SHA256.new, token, issued_at)
"v2.#{hmac}.#{issued_at}"
end
private_class_method :authorization_token
def self.request_kwargs(storage, timeout, remote_storage: nil)
metadata = {
'authorization' => "Bearer #{authorization_token(storage)}",
'client_name' => CLIENT_NAME
}
feature_stack = Thread.current[:gitaly_feature_stack]
feature = feature_stack && feature_stack[0]
metadata['call_site'] = feature.to_s if feature
metadata['gitaly-servers'] = address_metadata(remote_storage) if remote_storage
metadata['x-gitlab-correlation-id'] = Labkit::Correlation::CorrelationId.current_id if Labkit::Correlation::CorrelationId.current_id
metadata['gitaly-session-id'] = session_id if feature_enabled?(SERVER_FEATURE_CATFILE_CACHE)
metadata.merge!(server_feature_flags)
result = { metadata: metadata }
# nil timeout indicates that we should use the default
timeout = default_timeout if timeout.nil?
return result unless timeout > 0
deadline = real_time + timeout
result[:deadline] = deadline
result
end
def self.session_id
Gitlab::SafeRequestStore[:gitaly_session_id] ||= SecureRandom.uuid
end
def self.server_feature_flags
SERVER_FEATURE_FLAGS.map do |f|
["gitaly-feature-#{f.tr('_', '-')}", feature_enabled?(f).to_s]
end.to_h
end
def self.token(storage)
params = Gitlab.config.repositories.storages[storage]
raise "storage not found: #{storage.inspect}" if params.nil?
params['gitaly_token'].presence || Gitlab.config.gitaly['token']
end
def self.feature_enabled?(feature_name)
Feature::FlipperFeature.table_exists? && Feature.enabled?("gitaly_#{feature_name}")
rescue ActiveRecord::NoDatabaseError
false
end
# Ensures that Gitaly is not being abuse through n+1 misuse etc
def self.enforce_gitaly_request_limits(call_site)
# Only count limits in request-response environments (not sidekiq for example)
return unless Gitlab::SafeRequestStore.active?
# This is this actual number of times this call was made. Used for information purposes only
actual_call_count = increment_call_count("gitaly_#{call_site}_actual")
return unless enforce_gitaly_request_limits?
# Check if this call is nested within a allow_n_plus_1_calls
# block and skip check if it is
return if get_call_count(:gitaly_call_count_exception_block_depth) > 0
# This is the count of calls outside of a `allow_n_plus_1_calls` block
# It is used for enforcement but not statistics
permitted_call_count = increment_call_count("gitaly_#{call_site}_permitted")
count_stack
return if permitted_call_count <= MAXIMUM_GITALY_CALLS
raise TooManyInvocationsError.new(call_site, actual_call_count, max_call_count, max_stacks)
end
def self.enforce_gitaly_request_limits?
# We typically don't want to enforce request limits in production
# However, we have some production-like test environments, i.e., ones
# where `Rails.env.production?` returns `true`. We do want to be able to
# check if the limit is being exceeded while testing in those environments
# In that case we can use a feature flag to indicate that we do want to
# enforce request limits.
return true if feature_enabled?('enforce_requests_limits')
!(Rails.env.production? || ENV["GITALY_DISABLE_REQUEST_LIMITS"])
end
private_class_method :enforce_gitaly_request_limits?
def self.allow_n_plus_1_calls
return yield unless Gitlab::SafeRequestStore.active?
begin
increment_call_count(:gitaly_call_count_exception_block_depth)
yield
ensure
decrement_call_count(:gitaly_call_count_exception_block_depth)
end
end
# Normally a FindCommit RPC will cache the commit with its SHA
# instead of a ref name, since it's possible the branch is mutated
# afterwards. However, for read-only requests that never mutate the
# branch, this method allows caching of the ref name directly.
def self.allow_ref_name_caching
return yield unless Gitlab::SafeRequestStore.active?
return yield if ref_name_caching_allowed?
begin
Gitlab::SafeRequestStore[:allow_ref_name_caching] = true
yield
ensure
Gitlab::SafeRequestStore[:allow_ref_name_caching] = false
end
end
def self.ref_name_caching_allowed?
Gitlab::SafeRequestStore[:allow_ref_name_caching]
end
def self.get_call_count(key)
Gitlab::SafeRequestStore[key] || 0
end
private_class_method :get_call_count
def self.increment_call_count(key)
Gitlab::SafeRequestStore[key] ||= 0
Gitlab::SafeRequestStore[key] += 1
end
private_class_method :increment_call_count
def self.decrement_call_count(key)
Gitlab::SafeRequestStore[key] -= 1
end
private_class_method :decrement_call_count
# Returns the of the number of Gitaly calls made for this request
def self.get_request_count
get_call_count("gitaly_call_actual")
end
def self.reset_counts
return unless Gitlab::SafeRequestStore.active?
Gitlab::SafeRequestStore["gitaly_call_actual"] = 0
Gitlab::SafeRequestStore["gitaly_call_permitted"] = 0
end
def self.peek_enabled?
Gitlab::SafeRequestStore[:peek_enabled]
end
def self.add_call_details(details)
Gitlab::SafeRequestStore['gitaly_call_details'] ||= []
Gitlab::SafeRequestStore['gitaly_call_details'] << details
end
def self.list_call_details
return [] unless peek_enabled?
Gitlab::SafeRequestStore['gitaly_call_details'] || []
end
def self.expected_server_version
path = Rails.root.join(SERVER_VERSION_FILE)
path.read.chomp
end
def self.timestamp(time)
Google::Protobuf::Timestamp.new(seconds: time.to_i)
end
# The default timeout on all Gitaly calls
def self.default_timeout
return no_timeout if Sidekiq.server?
timeout(:gitaly_timeout_default)
end
def self.fast_timeout
timeout(:gitaly_timeout_fast)
end
def self.medium_timeout
timeout(:gitaly_timeout_medium)
end
def self.no_timeout
0
end
def self.timeout(timeout_name)
Gitlab::CurrentSettings.current_application_settings[timeout_name]
end
private_class_method :timeout
# Count a stack. Used for n+1 detection
def self.count_stack
return unless Gitlab::SafeRequestStore.active?
stack_string = Gitlab::Profiler.clean_backtrace(caller).drop(1).join("\n")
Gitlab::SafeRequestStore[:stack_counter] ||= Hash.new
count = Gitlab::SafeRequestStore[:stack_counter][stack_string] || 0
Gitlab::SafeRequestStore[:stack_counter][stack_string] = count + 1
end
private_class_method :count_stack
# Returns a count for the stack which called Gitaly the most times. Used for n+1 detection
def self.max_call_count
return 0 unless Gitlab::SafeRequestStore.active?
stack_counter = Gitlab::SafeRequestStore[:stack_counter]
return 0 unless stack_counter
stack_counter.values.max
end
private_class_method :max_call_count
# Returns the stacks that calls Gitaly the most times. Used for n+1 detection
def self.max_stacks
return unless Gitlab::SafeRequestStore.active?
stack_counter = Gitlab::SafeRequestStore[:stack_counter]
return unless stack_counter
max = max_call_count
return if max.zero?
stack_counter.select { |_, v| v == max }.keys
end
private_class_method :max_stacks
end
end