fix!: activerecord find_by_sql spans on Rails 7.0+ (#1184)

* fix: activerecord find_by_sql spans on Rails 7.0+

* tests: fix create_table call

* tests: rubocop tweak

* feat: call spans that produce reads `query`

* Refactor patching to use define_method

---------

Co-authored-by: Ariel Valentin <[email protected]>
Co-authored-by: Kayla Reopelle <[email protected]>

Author: 3 people

instrumentation/active_record/lib/opentelemetry/instrumentation/active_record/patches/querying.rb

@@ -18,9 +18,11 @@ class << base
 
           # Contains ActiveRecord::Querying to be patched
           module ClassMethods
-            def find_by_sql(...)
-              tracer.in_span("#{self}.find_by_sql") do
-                super
+            method_name = ::ActiveRecord.version >= Gem::Version.new('7.0.0') ? :_query_by_sql : :find_by_sql
+
+            define_method(method_name) do |*args, **kwargs|
+              tracer.in_span("#{self} query") do
+                super(*args, **kwargs)
               end
             end
 

instrumentation/active_record/test/instrumentation/active_record/patches/querying_test.rb

@@ -15,12 +15,18 @@
 
   before { exporter.reset }
 
-  describe 'find_by_sql' do
+  describe 'query' do
     it 'traces' do
+      Account.create!
+
       User.find_by_sql('SELECT * FROM users')
+      Account.first.users.to_a
+
+      user_find_spans = spans.select { |s| s.name == 'User query' }
+      account_find_span = spans.find { |s| s.name == 'Account query' }
 
-      find_span = spans.find { |s| s.name == 'User.find_by_sql' }
-      _(find_span).wont_be_nil
+      _(user_find_spans.length).must_equal(2)
+      _(account_find_span).wont_be_nil
     end
   end
 end

instrumentation/active_record/test/test_helper.rb

@@ -34,8 +34,14 @@
   database: 'db/development.sqlite3'
 )
 
-# Create User model
+# Create ActiveRecord models
+class Account < ActiveRecord::Base
+  has_many :users
+end
+
 class User < ActiveRecord::Base
+  belongs_to :account
+
   validate :name_if_present
 
   scope :recently_created, -> { where('created_at > ?', Time.now - 3600) }
@@ -54,9 +60,12 @@ class SuperUser < ActiveRecord::Base; end
 # Simple migration to create a table to test against
 class CreateUserTable < ActiveRecord::Migration[migration_version]
   def change
+    create_table :accounts, &:timestamps
+
     create_table :users do |t|
       t.string 'name'
       t.integer 'counter'
+      t.references 'account'
       t.timestamps
     end