Fix Grape API api_view method

[ansor4]

What does this PR do?

Grape 3.1.0 introduced a change that breaks fetching the api name from the instance. The change had removed the attr_reader on base for an API instance, resulting in an error when using this version of Grape with datadog.

[2026-02-11T21:59:57.943480 #17] ERROR -- datadog: [datadog] (/usr/local/bundle/gems/datadog-2.28.0/lib/datadog/tracing/contrib/grape/endpoint.rb:80:in 'Datadog::Tracing::Contrib::Grape::Endpoint.endpoint_start_process') undefined method 'base' for class #<Class:0x00007f61f1b194c8>

Motivation:

Above error prevented expected service names and values to show up on the dashboard.

Change log entry

Additional Notes:

How to test the change?

I was able to monkey-patch our service in the meantime and I'm see the expected values in the dashboard.

module DatadogGrapeFix
  def api_view(api)
    if defined?(::Grape::API::Instance) && api <= ::Grape::API::Instance && api.respond_to?(:base)
      api.base.to_s
    else
      api.to_s
    end
  end
end

Datadog::Tracing::Contrib::Grape::Endpoint.singleton_class.prepend(DatadogGrapeFix)

[vpellan]

Launched CI

[p-datadog]

Looking at our appraisals, ruby 4.0 specifies grape < 2.3 (I find it weird that most recent ruby has a requirement of an old grape) and the other MRIs have no grape version constraint. Should we distribute < 1.2, <2.3, 2.3 and 3.0 / 3.1 grape versions throughout the various ruby versions?

[p-datadog]

Looking at our appraisals, ruby 4.0 specifies grape < 2.3 (I find it weird that most recent ruby has a requirement of an old grape) and the other MRIs have no grape version constraint. Should we distribute < 1.2, <2.3, 2.3 and 3.0 / 3.1 grape versions throughout the various ruby versions?

[vpellan]

Hello! Thanks for your contribution! We're looking at merging this PR and once it's done, we'll merge this one too

[ivoanjo]

I believe this fixes #5359

[vpellan]

@ivoanjo is right, we need this fix to be able to support 3.1.x, which means we first need to merge this PR before merging #5414. I'm going to update it with latest master, apply reviews and merge it