Merge pull request #295 from DataDog/delner/add_graphql_configuration

Add GraphQL configuration

Appraisals

@@ -115,6 +115,7 @@ if RUBY_VERSION >= '2.2.2' && RUBY_PLATFORM != 'java'
   appraise 'contrib' do
     gem 'elasticsearch-transport'
     gem 'mongo', '< 2.5'
+    gem 'graphql'
     gem 'grape'
     gem 'rack'
     gem 'rack-test'

Rakefile

@@ -48,6 +48,7 @@ namespace :spec do
     :rack,
     :faraday,
     :grape,
+    :graphql,
     :aws,
     :sucker_punch,
     :mongodb,
@@ -108,18 +109,19 @@ namespace :test do
   end
 
   [
+    :aws,
     :elasticsearch,
-    :http,
-    :redis,
-    :sinatra,
-    :sidekiq,
-    :rack,
     :faraday,
     :grape,
-    :aws,
-    :sucker_punch,
+    :http,
     :mongodb,
-    :resque
+    :resque,
+    :rack,
+    :redis,
+    :resque,
+    :sidekiq,
+    :sinatra,
+    :sucker_punch
   ].each do |contrib|
     Rake::TestTask.new(contrib) do |t|
       t.libs << %w[test lib]
@@ -230,6 +232,7 @@ task :ci do
     # RSpec
     sh 'rvm $MRI_VERSIONS --verbose do appraisal contrib rake spec:active_record'
     sh 'rvm $MRI_VERSIONS --verbose do appraisal contrib rake spec:dalli'
+    sh 'rvm $MRI_VERSIONS --verbose do appraisal contrib rake spec:graphql'
     sh 'rvm $MRI_VERSIONS --verbose do appraisal contrib rake spec:racecar'
     sh 'rvm $MRI_OLD_VERSIONS --verbose do appraisal contrib-old rake spec:dalli'
     sh 'rvm $MRI_OLD_VERSIONS --verbose do appraisal contrib-old rake spec:active_record'

docs/GettingStarted.md

@@ -41,6 +41,7 @@ For further details and options, check our integrations list.
 * [Ruby on Rails](#Ruby_on_Rails)
 * [Sinatra](#Sinatra)
 * [Rack](#Rack)
+* [GraphQL](#GraphQL)
 * [Grape](#Grape)
 * [Active Record](#Active_Record)
 * [Elastic Search](#Elastic_Search)
@@ -144,6 +145,57 @@ Where `options` is an optional `Hash` that accepts the following parameters:
 
 ## Other libraries
 
+### GraphQL
+
+*Version 1.7.9+ supported*
+
+The GraphQL integration activates instrumentation for GraphQL queries. To activate your integration, use the ``Datadog.configure`` method:
+
+    # Inside Rails initializer or equivalent
+    Datadog.configure do |c|
+      c.use :graphql,
+            service_name: 'graphql',
+            schemas: [YourSchema]
+    end
+
+    # Then run a GraphQL query
+    YourSchema.execute(query, variables: {}, context: {}, operation_name: nil)
+
+The `use :graphql` method accepts the following parameters:
+
+| Key | Description | Default |
+| --- | --- | --- |
+| ``service_name`` | Service name used for `graphql` instrumentation | ``ruby-graphql`` |
+| ``schemas`` | Required. Array of `GraphQL::Schema` objects which to trace. Tracing will be added to all the schemas listed, using the options provided to this configuration. If you do not provide any, then tracing will not be activated. | ``[]`` |
+| ``tracer`` | A ``Datadog::Tracer`` instance used to instrument the application. Usually you don't need to set that. | ``Datadog.tracer`` |
+
+##### Manually configuring GraphQL schemas
+
+If you prefer to individually configure the tracer settings for a schema (e.g. you have multiple schemas with different service names),
+in the schema definition, you can add the following [using the GraphQL API](http://graphql-ruby.org/queries/tracing.html):
+
+```
+YourSchema = GraphQL::Schema.define do
+  use(
+    GraphQL::Tracing::DataDogTracing,
+    service: 'graphql'
+  )
+end
+```
+
+Or you can modify an already defined schema:
+
+```
+YourSchema.define do
+  use(
+    GraphQL::Tracing::DataDogTracing,
+    service: 'graphql'
+  )
+end
+```
+
+Do *not* `use :graphql` in `Datadog.configure` if you choose to configure manually, as to avoid double tracing. These two means of configuring GraphQL tracing are considered mutually exclusive.
+
 ### Grape
 
 The Grape integration adds the instrumentation to Grape endpoints and filters. This integration can work side by side

gemfiles/contrib.gemfile

@@ -5,6 +5,7 @@ source "https://rubygems.org"
 gem "pry-nav", git: "https://github.com/nixme/pry-nav.git", branch: "master"
 gem "elasticsearch-transport"
 gem "mongo", "< 2.5"
+gem "graphql"
 gem "grape"
 gem "rack"
 gem "rack-test"

lib/ddtrace.rb

@@ -59,6 +59,7 @@ def configure(target = configuration, opts = {})
 require 'ddtrace/contrib/elasticsearch/patcher'
 require 'ddtrace/contrib/faraday/patcher'
 require 'ddtrace/contrib/grape/patcher'
+require 'ddtrace/contrib/graphql/patcher'
 require 'ddtrace/contrib/redis/patcher'
 require 'ddtrace/contrib/http/patcher'
 require 'ddtrace/contrib/aws/patcher'

lib/ddtrace/contrib/graphql/patcher.rb

@@ -0,0 +1,57 @@
+require 'ddtrace/ext/app_types'
+require 'ddtrace/ext/http'
+
+module Datadog
+  module Contrib
+    module GraphQL
+      # Provides instrumentation for `graphql` through the GraphQL tracing framework
+      module Patcher
+        include Base
+        register_as :graphql
+
+        option :tracer, default: Datadog.tracer
+        option :service_name, default: 'ruby-graphql', depends_on: [:tracer] do |value|
+          get_option(:tracer).set_service_info(value, 'ruby-graphql', Ext::AppTypes::WEB)
+          value
+        end
+        option :schemas
+
+        class << self
+          def patch
+            return patched? if patched? || !compatible? || get_option(:schemas).nil?
+
+            get_option(:schemas).each { |s| patch_schema!(s) }
+
+            @patched = true
+          end
+
+          def patch_schema!(schema)
+            tracer = get_option(:tracer)
+            service_name = get_option(:service_name)
+
+            schema.define do
+              use(
+                ::GraphQL::Tracing::DataDogTracing,
+                tracer: tracer,
+                service: service_name
+              )
+            end
+          end
+
+          def patched?
+            return @patched if defined?(@patched)
+            @patched = false
+          end
+
+          private
+
+          def compatible?
+            defined?(::GraphQL) \
+              && defined?(::GraphQL::Tracing::DataDogTracing) \
+              && Gem.loaded_specs['graphql'].version >= Gem::Version.new('1.7.9')
+          end
+        end
+      end
+    end
+  end
+end

spec/ddtrace/contrib/graphql/test_types.rb

@@ -0,0 +1,54 @@
+LogHelpers.without_warnings do
+  require 'graphql'
+end
+
+RSpec.shared_context 'GraphQL test schema' do
+  let(:schema) do
+    qt = query_type
+
+    ::GraphQL::Schema.define do
+      query(qt)
+    end
+  end
+
+  let(:query_type_name) { 'Query' }
+  let(:query_type) do
+    qtn = query_type_name
+    ot = object_type
+    oc = object_class
+
+    ::GraphQL::ObjectType.define do
+      name qtn
+      field ot.name.downcase.to_sym do
+        type ot
+        argument :id, !types.ID
+        description 'Find an object by ID'
+        resolve ->(_obj, args, _ctx) { oc.new(args['id']) }
+      end
+    end
+  end
+
+  let(:object_type_name) { 'Foo' }
+  let(:object_type) do
+    otn = object_type_name
+
+    ::GraphQL::ObjectType.define do
+      name otn
+      field :id, !types.ID
+      field :name, types.String
+      field :created_at, !types.String
+      field :updated_at, !types.String
+    end
+  end
+
+  let(:object_class) do
+    Class.new do
+      attr_accessor :id, :name
+
+      def initialize(id, name = 'bar')
+        @id = id
+        @name = name
+      end
+    end
+  end
+end

spec/ddtrace/contrib/graphql/tracer_spec.rb

@@ -0,0 +1,73 @@
+require 'spec_helper'
+require 'ddtrace/contrib/graphql/test_types'
+
+require 'ddtrace'
+
+# rubocop:disable Metrics/BlockLength
+RSpec.describe 'GraphQL patcher' do
+  include_context 'GraphQL test schema'
+
+  # GraphQL generates tons of warnings.
+  # This suppresses those warnings. 
+  around(:each) do |example|
+    without_warnings do
+      example.run
+    end
+  end
+
+  let(:tracer) { ::Datadog::Tracer.new(writer: FauxWriter.new) }
+
+  def pop_spans
+    tracer.writer.spans(:keep)
+  end
+
+  let(:all_spans) { pop_spans }
+  let(:root_span) { all_spans.find { |s| s.parent.nil? } }
+
+  before(:each) do
+    Datadog.configure do |c|
+      c.use :graphql,
+            service_name: 'graphql-test',
+            tracer: tracer,
+            schemas: [schema]
+    end
+  end
+
+  describe 'query trace' do
+    subject(:result) { schema.execute(query, variables: {}, context: {}, operation_name: nil) }
+
+    let(:query) { '{ foo(id: 1) { name } }' }
+    let(:variables) { {} }
+    let(:context) { {} }
+    let(:operation_name) { nil }
+
+    it do
+      # Expect no errors
+      expect(result.to_h['errors']).to be nil
+
+      # Expect nine spans
+      expect(all_spans).to have(9).items
+
+      # List of valid resource names
+      # (If this is too brittle, revist later.)
+      valid_resource_names = [
+        'Query.foo',
+        'analyze.graphql',
+        'execute.graphql',
+        'lex.graphql',
+        'parse.graphql',
+        'validate.graphql'
+      ]
+
+      # Expect root span to be 'execute.graphql'
+      expect(root_span.name).to eq('execute.graphql')
+      expect(root_span.resource).to eq('execute.graphql')
+
+      # Expect each span to be properly named
+      all_spans.each do |span|
+        expect(span.service).to eq('graphql-test')
+        expect(valid_resource_names).to include(span.resource.to_s)
+      end
+    end
+  end
+end

spec/spec_helper.rb

@@ -16,6 +16,7 @@
 # require 'support/rails_active_record_helpers'
 # require 'support/configuration_helpers'
 require 'support/synchronization_helpers'
+require 'support/log_helpers'
 
 WebMock.allow_net_connect!
 WebMock.disable!
@@ -25,6 +26,7 @@
   # config.include RailsActiveRecordHelpers
   # config.include ConfigurationHelpers
   config.include SynchronizationHelpers
+  config.include LogHelpers
 
   config.expect_with :rspec do |expectations|
     expectations.include_chain_clauses_in_custom_matcher_descriptions = true

spec/support/log_helpers.rb

@@ -0,0 +1,15 @@
+module LogHelpers
+  def without_warnings(&block)
+    LogHelpers.without_warnings(&block)
+  end
+
+  def self.without_warnings
+    v = $VERBOSE
+    $VERBOSE = nil
+    begin
+      yield
+    ensure
+      $VERBOSE = v
+    end
+  end
+end