50 lines
1.3 KiB
Ruby
50 lines
1.3 KiB
Ruby
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# frozen_string_literal: true
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# This class is used to log messages to a specified logger from within a `Signal.trap` context. Most loggers rely on
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# methods that are prohibited within a `Signal.trap` context, so this class is used to queue up log messages and then
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# log them from a separate thread outside of the `Signal.trap` context.
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#
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# Example:
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# Signal.trap("USR1") do
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# SignalTrapLogger.instance.log(Rails.logger, "Received USR1 signal")
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# end
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#
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# Do note that you need to call `SignalTrapLogger.instance.after_fork` after forking a new process to ensure that the
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# logging thread is running in the new process.
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class SignalTrapLogger
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include Singleton
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def initialize
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@queue = Queue.new
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ensure_logging_thread_running
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end
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def log(logger, message, level: :info)
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@queue << { logger:, message:, level: }
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end
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def after_fork
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ensure_logging_thread_running
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end
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private
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def ensure_logging_thread_running
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return if @thread&.alive?
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@thread =
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Thread.new do
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loop do
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begin
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log_entry = @queue.pop
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log_entry[:logger].public_send(log_entry[:level], log_entry[:message])
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rescue => error
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Rails.logger.error(
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"Error in SignalTrapLogger thread: #{error.message}\n#{error.backtrace.join("\n")}",
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)
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end
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end
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end
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end
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end
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