talos

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// This Source Code Form is subject to the terms of the Mozilla Public
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// License, v. 2.0. If a copy of the MPL was not distributed with this
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// file, You can obtain one at http://mozilla.org/MPL/2.0/.
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package logging
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import (
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	"sync/atomic"
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	"go.uber.org/zap/zapcore"
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)
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// NewControllerErrorSuppressor creates a new controller error suppressor.
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//
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// It suppresses error logs for a given controller unless it logs >= threshold errors.
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// The idea is that all controllers reconcile errors, so if the error is not transient,
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// it will be reported enough time to hit the threshold, but transient errors will be
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// suppressed.
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//
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// The suppressor records the controller name by inspecting a log field named "controller"
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// passed via `logger.With()` call.
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func NewControllerErrorSuppressor(core zapcore.Core, threshold int64) zapcore.Core {
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	return &consoleSampler{
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		Core:      core,
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		threshold: threshold,
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	}
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}
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type consoleSampler struct {
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	zapcore.Core
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	hits       *atomic.Int64
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	threshold  int64
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	controller string
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}
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var _ zapcore.Core = (*consoleSampler)(nil)
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func (s *consoleSampler) Level() zapcore.Level {
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	return zapcore.LevelOf(s.Core)
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}
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func (s *consoleSampler) With(fields []zapcore.Field) zapcore.Core {
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	controller := s.controller
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	num := s.hits
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	for _, field := range fields {
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		if field.Key == "controller" {
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			if field.String != controller {
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				controller = field.String
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				num = new(atomic.Int64)
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			}
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			break
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		}
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	}
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	return &consoleSampler{
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		threshold:  s.threshold,
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		controller: controller,
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		hits:       num,
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		Core:       s.Core.With(fields),
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	}
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}
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func (s *consoleSampler) Check(ent zapcore.Entry, ce *zapcore.CheckedEntry) *zapcore.CheckedEntry {
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	if !s.Enabled(ent.Level) {
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		return ce
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	}
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	if ent.Level == zapcore.ErrorLevel && s.controller != "" {
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		if s.hits.Add(1) <= s.threshold {
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			// suppress the log
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			return ce
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		}
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	}
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	return s.Core.Check(ent, ce)
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}
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