HTTP instrumentation incompatible with http gem v6.0

[timrossinfo]

The HTTP client instrumentation in ScoutApm::Instruments::HTTP is incompatible with http gem v6.0+, which changed HTTP::Client#request from positional arguments to keyword arguments.

Error

ArgumentError: wrong number of arguments (given 3, expected 2)

Root Cause

Both the prepend and alias instrumentation paths in lib/scout_apm/instruments/http.rb pass opts as a third positional argument to HTTP::Client#request. In http v5, the method accepted (verb, uri, opts = {}). In v6, the signature changed to (verb, uri, **opts) - keyword arguments only - so the third positional argument raises an ArgumentError.

[lancetarn]

Proposed Fix

Root cause: ScoutApm::Instruments::HTTP passes opts as a positional third argument to HTTP::Client#request. In http gem v6.0+, the method signature changed from (verb, uri, opts = {}) to (verb, uri, **opts) (keyword arguments only), causing ArgumentError: wrong number of arguments (given 3, expected 2).

Fix: Add version detection via Gem::Version.new(::HTTP::VERSION) and branch instrumentation accordingly:

• http gem < 6.0: Keep existing positional opts = {} (unchanged behavior)
• http gem >= 6.0: Use keyword splat **opts via new HTTPInstrumentationPrependV6 module and corresponding alias path

Files changed:

• lib/scout_apm/instruments/http.rb — version-aware instrumentation for both prepend and alias paths
• test/unit/instruments/http_test.rb — updated to assert correct module used per version

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Plan generated with Claude Code