Prevent exchange logging crash #12100
Merged
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Proposed Changes
Don't let the
log
callback of exchange_logging handler crash, because in case of a crash OTP logger removes theexchange_logger handler (https://github.com/erlang/otp/blob/OTP-27.0/lib/kernel/src/logger_backend.erl#L54), which in turn deletes the log exchange and its bindings.
It was seen several times in production (even on 3.13.x) that the log exchange suddenly disappears and without debug logging there is no trace of why. (The OTP logger framework does print the details, but on debug level only https://github.com/erlang/otp/blob/OTP-27.0/lib/kernel/src/logger_backend.erl#L59)
With this commit
erlang:display
will print the reason and stacktrace to stderr without using the logging infrastructure.This hopefully will give some hints about the root cause (which is still unknown)
Tested the change manually using
meck
to mock a crash of the logging for a certain log event.Types of Changes
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