debian-mirror-gitlab/app/services/metrics/dashboard/grafana_metric_embed_service.rb
2020-04-22 19:07:51 +05:30

177 lines
5 KiB
Ruby

# frozen_string_literal: true
# Responsible for returning a gitlab-compatible dashboard
# containing info based on a grafana dashboard and datasource.
#
# Use Gitlab::Metrics::Dashboard::Finder to retrive dashboards.
module Metrics
module Dashboard
class GrafanaMetricEmbedService < ::Metrics::Dashboard::BaseEmbedService
include ReactiveCaching
SEQUENCE = [
::Gitlab::Metrics::Dashboard::Stages::GrafanaFormatter,
::Gitlab::Metrics::Dashboard::Stages::PanelIdsInserter
].freeze
self.reactive_cache_key = ->(service) { service.cache_key }
self.reactive_cache_lease_timeout = 30.seconds
self.reactive_cache_refresh_interval = 30.minutes
self.reactive_cache_lifetime = 30.minutes
self.reactive_cache_worker_finder = ->(_id, *args) { from_cache(*args) }
class << self
# Determines whether the provided params are sufficient
# to uniquely identify a grafana dashboard.
def valid_params?(params)
[
embedded?(params[:embedded]),
params[:grafana_url]
].all?
end
def from_cache(project_id, user_id, grafana_url)
project = Project.find(project_id)
user = User.find(user_id)
new(project, user, grafana_url: grafana_url)
end
end
def get_dashboard
with_reactive_cache(*cache_key) { |result| result }
end
# Inherits the primary logic from the parent class and
# maintains the service's API while including ReactiveCache
def calculate_reactive_cache(*)
# This is called with explicit parentheses to prevent
# the params passed to #calculate_reactive_cache from
# being passed to #get_dashboard (which accepts none)
::Metrics::Dashboard::BaseService
.instance_method(:get_dashboard)
.bind(self)
.call() # rubocop:disable Style/MethodCallWithoutArgsParentheses
end
def cache_key(*args)
[project.id, current_user.id, grafana_url]
end
# Required for ReactiveCaching; Usage overridden by
# self.reactive_cache_worker_finder
def id
nil
end
private
def get_raw_dashboard
raise MissingIntegrationError unless client
grafana_dashboard = fetch_dashboard
datasource = fetch_datasource(grafana_dashboard)
params.merge!(grafana_dashboard: grafana_dashboard, datasource: datasource)
{}
end
def fetch_dashboard
uid = GrafanaUidParser.new(grafana_url, project).parse
raise DashboardProcessingError.new('Dashboard uid not found') unless uid
response = client.get_dashboard(uid: uid)
parse_json(response.body)
end
def fetch_datasource(dashboard)
name = DatasourceNameParser.new(grafana_url, dashboard).parse
raise DashboardProcessingError.new('Datasource name not found') unless name
response = client.get_datasource(name: name)
parse_json(response.body)
end
def grafana_url
params[:grafana_url]
end
def client
project.grafana_integration&.client
end
def allowed?
Ability.allowed?(current_user, :read_project, project)
end
def sequence
SEQUENCE
end
def parse_json(json)
JSON.parse(json, symbolize_names: true)
rescue JSON::ParserError
raise DashboardProcessingError.new('Grafana response contains invalid json')
end
end
# Identifies the uid of the dashboard based on url format
class GrafanaUidParser
def initialize(grafana_url, project)
@grafana_url, @project = grafana_url, project
end
def parse
@grafana_url.match(uid_regex) { |m| m.named_captures['uid'] }
end
private
# URLs are expected to look like https://domain.com/d/:uid/other/stuff
def uid_regex
base_url = @project.grafana_integration.grafana_url.chomp('/')
%r{^(#{Regexp.escape(base_url)}\/d\/(?<uid>.+)\/)}x
end
end
# Identifies the name of the datasource for a dashboard
# based on the panelId query parameter found in the url.
#
# If no panel is specified, defaults to the first valid panel.
class DatasourceNameParser
def initialize(grafana_url, grafana_dashboard)
@grafana_url, @grafana_dashboard = grafana_url, grafana_dashboard
end
def parse
@grafana_dashboard[:dashboard][:panels]
.find { |panel| panel_id ? matching_panel?(panel) : valid_panel?(panel) }
.try(:[], :datasource)
end
private
def panel_id
query_params[:panelId]
end
def query_params
Gitlab::Metrics::Dashboard::Url.parse_query(@grafana_url)
end
def matching_panel?(panel)
panel[:id].to_s == panel_id
end
def valid_panel?(panel)
::Grafana::Validator
.new(@grafana_dashboard, nil, panel, query_params)
.valid?
end
end
end
end