124 lines
3.4 KiB
Ruby
124 lines
3.4 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
module Prometheus
|
|
class ProxyService < BaseService
|
|
include ReactiveCaching
|
|
include Gitlab::Utils::StrongMemoize
|
|
|
|
self.reactive_cache_key = ->(service) { [] }
|
|
self.reactive_cache_lease_timeout = 30.seconds
|
|
|
|
# reactive_cache_refresh_interval should be set to a value higher than
|
|
# reactive_cache_lifetime. If the refresh_interval is less than lifetime
|
|
# then the ReactiveCachingWorker will re-query prometheus for this
|
|
# PromQL query even though it's (probably) already been picked up by
|
|
# the frontend
|
|
# refresh_interval should be set less than lifetime only if this data
|
|
# is expected to change *and* be fetched again by the frontend
|
|
self.reactive_cache_refresh_interval = 90.seconds
|
|
self.reactive_cache_lifetime = 1.minute
|
|
self.reactive_cache_worker_finder = ->(_id, *args) { from_cache(*args) }
|
|
|
|
attr_accessor :proxyable, :method, :path, :params
|
|
|
|
PROXY_SUPPORT = {
|
|
'query' => {
|
|
method: ['GET'],
|
|
params: %w(query time timeout)
|
|
},
|
|
'query_range' => {
|
|
method: ['GET'],
|
|
params: %w(query start end step timeout)
|
|
}
|
|
}.freeze
|
|
|
|
def self.from_cache(proxyable_class_name, proxyable_id, method, path, params)
|
|
proxyable_class = begin
|
|
proxyable_class_name.constantize
|
|
rescue NameError
|
|
nil
|
|
end
|
|
return unless proxyable_class
|
|
|
|
proxyable = proxyable_class.find(proxyable_id)
|
|
|
|
new(proxyable, method, path, params)
|
|
end
|
|
|
|
# proxyable can be any model which responds to .prometheus_adapter
|
|
# like Environment.
|
|
def initialize(proxyable, method, path, params)
|
|
@proxyable = proxyable
|
|
@path = path
|
|
|
|
# Convert ActionController::Parameters to hash because reactive_cache_worker
|
|
# does not play nice with ActionController::Parameters.
|
|
@params = filter_params(params, path).to_hash
|
|
|
|
@method = method
|
|
end
|
|
|
|
def id
|
|
nil
|
|
end
|
|
|
|
def execute
|
|
return cannot_proxy_response unless can_proxy?
|
|
return no_prometheus_response unless can_query?
|
|
|
|
with_reactive_cache(*cache_key) do |result|
|
|
result
|
|
end
|
|
end
|
|
|
|
def calculate_reactive_cache(proxyable_class_name, proxyable_id, method, path, params)
|
|
return no_prometheus_response unless can_query?
|
|
|
|
response = prometheus_client_wrapper.proxy(path, params)
|
|
|
|
success(http_status: response.code, body: response.body)
|
|
rescue Gitlab::PrometheusClient::Error => err
|
|
service_unavailable_response(err)
|
|
end
|
|
|
|
def cache_key
|
|
[@proxyable.class.name, @proxyable.id, @method, @path, @params]
|
|
end
|
|
|
|
private
|
|
|
|
def service_unavailable_response(exception)
|
|
error(exception.message, :service_unavailable)
|
|
end
|
|
|
|
def no_prometheus_response
|
|
error('No prometheus server found', :service_unavailable)
|
|
end
|
|
|
|
def cannot_proxy_response
|
|
error('Proxy support for this API is not available currently')
|
|
end
|
|
|
|
def prometheus_adapter
|
|
strong_memoize(:prometheus_adapter) do
|
|
@proxyable.prometheus_adapter
|
|
end
|
|
end
|
|
|
|
def prometheus_client_wrapper
|
|
prometheus_adapter&.prometheus_client
|
|
end
|
|
|
|
def can_query?
|
|
prometheus_adapter&.can_query?
|
|
end
|
|
|
|
def filter_params(params, path)
|
|
params.slice(*PROXY_SUPPORT.dig(path, :params))
|
|
end
|
|
|
|
def can_proxy?
|
|
PROXY_SUPPORT.dig(@path, :method)&.include?(@method)
|
|
end
|
|
end
|
|
end
|