From e2a033780d5cb168b85967e7fc5fe7f355368280 Mon Sep 17 00:00:00 2001
From: arjun-rajappa <Arjun.Rajappa@ibm.com>
Date: Wed, 21 Aug 2024 13:00:29 +0530
Subject: [PATCH] feature: instrument sequel gem

Signed-off-by: arjun-rajappa <Arjun.Rajappa@ibm.com>
---
 lib/instana/activators/sequel.rb      | 21 ++++++++++++++
 lib/instana/config.rb                 |  1 +
 lib/instana/instrumentation/sequel.rb | 41 +++++++++++++++++++++++++++
 lib/instana/tracing/span.rb           |  4 +--
 4 files changed, 65 insertions(+), 2 deletions(-)
 create mode 100644 lib/instana/activators/sequel.rb
 create mode 100644 lib/instana/instrumentation/sequel.rb

diff --git a/lib/instana/activators/sequel.rb b/lib/instana/activators/sequel.rb
new file mode 100644
index 00000000..558f3140
--- /dev/null
+++ b/lib/instana/activators/sequel.rb
@@ -0,0 +1,21 @@
+# (c) Copyright IBM Corp. 2021
+# (c) Copyright Instana Inc. 2021
+
+module Instana
+  module Activators
+    class Sequel < Activator
+      def can_instrument?
+        defined?(::Sequel::Database)
+      end
+
+      def instrument
+        require 'instana/instrumentation/sequel'
+
+        ::Sequel::Database
+          .prepend(Instana::Instrumentation::Sequel)
+
+        true
+      end
+    end
+  end
+end
diff --git a/lib/instana/config.rb b/lib/instana/config.rb
index c44937ef..539b28c8 100644
--- a/lib/instana/config.rb
+++ b/lib/instana/config.rb
@@ -73,6 +73,7 @@ def initialize(logger: ::Instana.logger, agent_host: ENV['INSTANA_AGENT_HOST'],
       @config[:'resque-client']    = { :enabled => true, :propagate => true }
       @config[:'resque-worker']    = { :enabled => true, :'setup-fork' => true }
       @config[:'rest-client']      = { :enabled => true }
+      @config[:sequel] = { :enabled => true }
       @config[:'sidekiq-client']   = { :enabled => true }
       @config[:'sidekiq-worker']   = { :enabled => true }
     end
diff --git a/lib/instana/instrumentation/sequel.rb b/lib/instana/instrumentation/sequel.rb
new file mode 100644
index 00000000..a50b2852
--- /dev/null
+++ b/lib/instana/instrumentation/sequel.rb
@@ -0,0 +1,41 @@
+# (c) Copyright IBM Corp. 2024
+
+module Instana
+  module Instrumentation
+    module Sequel
+      IGNORED_SQL = %w[BEGIN COMMIT SET].freeze
+      SANITIZE_REGEXP = /('[\s\S][^']*'|\d*\.\d+|\d+|NULL)/i.freeze
+
+      def log_connection_yield(sql, conn, *args)
+        call_payload = {
+          sequel: {
+            adapter: opts[:adapter],
+            host: opts[:host],
+            username: opts[:user],
+            db: opts[:database],
+            sql: maybe_sanitize(sql)
+          }
+        }
+        maybe_trace(call_payload) { super(sql, conn, *args) }
+      end
+
+      private
+
+      def maybe_sanitize(sql)
+        ::Instana.config[:sanitize_sql] ? sql.gsub(SANITIZE_REGEXP, '?') : sql
+      end
+
+      def maybe_trace(call_payload, &blk)
+        if ::Instana.tracer.tracing? && !ignored?(call_payload)
+          ::Instana.tracer.trace(:sequel, call_payload, &blk)
+        else
+          yield
+        end
+      end
+
+      def ignored?(call_payload)
+        IGNORED_SQL.any? { |s| call_payload[:sequel][:sql].upcase.start_with?(s) }
+      end
+    end
+  end
+end
diff --git a/lib/instana/tracing/span.rb b/lib/instana/tracing/span.rb
index 6762bdf0..9847c3a5 100644
--- a/lib/instana/tracing/span.rb
+++ b/lib/instana/tracing/span.rb
@@ -7,12 +7,12 @@ class Span
                          :memcache, :'net-http', :rack, :render, :'rpc-client',
                          :'rpc-server', :'sidekiq-client', :'sidekiq-worker',
                          :redis, :'resque-client', :'resque-worker', :'graphql.server', :dynamodb, :s3, :sns, :sqs, :'aws.lambda.entry', :activejob, :log, :"mail.actionmailer",
-                         :"aws.lambda.invoke", :mongo ].freeze
+                         :"aws.lambda.invoke", :mongo, :sequel ].freeze
     ENTRY_SPANS = [ :rack, :'resque-worker', :'rpc-server', :'sidekiq-worker', :'graphql.server', :sqs,
                     :'aws.lambda.entry' ].freeze
     EXIT_SPANS = [ :activerecord, :excon, :'net-http', :'resque-client',
                    :'rpc-client', :'sidekiq-client', :redis, :dynamodb, :s3, :sns, :sqs, :log, :"mail.actionmailer",
-                   :"aws.lambda.invoke", :mongo ].freeze
+                   :"aws.lambda.invoke", :mongo, :sequel ].freeze
     HTTP_SPANS = [ :rack, :excon, :'net-http' ].freeze
 
     attr_accessor :parent