feat: Add ActiveStorage instrumentation

[ymtdzzz]

Description

Adding support for instrumenting ActiveStorage using ActiveSupport::Notification.

related: #1307

Test

Example script

$ cd instrumentation/active_storage/example
$ ruby trace_demonstration.rb

#<struct OpenTelemetry::SDK::Trace::SpanData
 name="service_upload.active_storage",
 kind=:internal,
 status=#<OpenTelemetry::Trace::Status:0x000000012b2df308 @code=1, @description="">,
 parent_span_id="\x00\x00\x00\x00\x00\x00\x00\x00",
 total_recorded_attributes=2,
 total_recorded_events=0,
 total_recorded_links=0,
 start_timestamp=1736671214398000000,
 end_timestamp=1736671214398395000,
 attributes={"active_storage.checksum"=>"x4UGDIZnlswqFwjJlxVMjg==", "active_storage.service"=>"Disk"},
 links=nil,
 events=nil,
 resource=
  #<OpenTelemetry::SDK::Resources::Resource:0x000000011f5bd810
   @attributes=
    {"service.name"=>"unknown_service",
     "process.pid"=>98542,
     "process.command"=>"trace_demonstration.rb",
     "process.runtime.name"=>"ruby",
     "process.runtime.version"=>"3.2.5",
     "process.runtime.description"=>"ruby 3.2.5 (2024-07-26 revision 31d0f1a2e7) [arm64-darwin23]",
     "telemetry.sdk.name"=>"opentelemetry",
     "telemetry.sdk.language"=>"ruby",
     "telemetry.sdk.version"=>"1.6.0"}>,
 instrumentation_scope=#<struct OpenTelemetry::SDK::InstrumentationScope name="OpenTelemetry::Instrumentation::ActiveStorage", version="0.0.0">,
 span_id="\xCA$\xA1\xD6\x01RV\x95",
 trace_id="\x13~\xDF\x02\x1F\x8C\xF3\x8B\x96\xA0\x97\xC3)}\x9A\xFA",
 trace_flags=#<OpenTelemetry::Trace::TraceFlags:0x000000012a539050 @flags=1>,
 tracestate=#<OpenTelemetry::Trace::Tracestate:0x000000012a536508 @hash={}>>

With other instrumentations in your Rails app

Without ActiveStorage instrumentation

# config/initializers/opentelemetry.rb
require "opentelemetry/sdk"

# install all compatible instrumentation with default configuration
OpenTelemetry::SDK.configure do |c|
  c.service_name = "otel-ruby-development"
  c.use "OpenTelemetry::Instrumentation::ActionPack"
  c.use "OpenTelemetry::Instrumentation::ActiveRecord"
  # c.use "OpenTelemetry::Instrumentation::ActiveStorage"
  c.use "OpenTelemetry::Instrumentation::ActiveJob"
end

With ActiveStorage instrumentation

# config/initializers/opentelemetry.rb
require "opentelemetry/sdk"

# install all compatible instrumentation with default configuration
OpenTelemetry::SDK.configure do |c|
  c.service_name = "otel-ruby-development"
  c.use "OpenTelemetry::Instrumentation::ActionPack"
  c.use "OpenTelemetry::Instrumentation::ActiveRecord"
  c.use "OpenTelemetry::Instrumentation::ActiveStorage", { key: :include, url: :include }
  c.use "OpenTelemetry::Instrumentation::ActiveJob"
end

[kaylareopelle]

Thank you, @ymtdzzz! I'm looking forward to OTel to offering ActiveStorage support.

[kaylareopelle]

Thanks for all the updates! 😄

The last thing I can think of would be to update the CODEOWNERS file to add your name to the list of reviewers. The OpenTelemetry Ruby team needs help from end users and other experts in the community to maintain our instrumentation. Since you built this Active Storage instrumentation, we'd love for you to help us maintain the library going forward. By becoming a CODEOWNER, you would be added as a reviewer to any PR opened to update the instrumentaiton/active_storage code. We may also tag you directly in issues raised regarding the Active Storage instrumentation.

Would you be comfortable with this?

I'd also like @xuan-cao-swi to take another look when he has a chance.

[ymtdzzz]

@kaylareopelle

Thank you for the suggestion!

Of course I'm happy to help with reviews and issues regarding the instrumentation!
I've added my name to the CODEOWNERS in b5a65bd .

I'm looking forward to collaborating with the team!