fix: Replace Context stack on clear #1598
Merged
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As identified in open-telemetry/opentelemetry-ruby-contrib#772, Rails copies all thread-local variables in
ActionController::Live
. Our use of an array to back theContext
stack results in two threads sharing the same stack.Context.clear
only clears the array, but continues to share it (in fact, its effect is visible to both threads), so there is no way to cleanly separate the thread'sContext
stacks using the public API.This PR replaces the
stack.clear
call with assignment of a new array to the thread-local. This allows a pattern like: