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				https://github.com/superseriousbusiness/gotosocial.git
				synced 2025-10-29 19:52:24 -05:00 
			
		
		
		
	* feat: Initial OTEL metrics * docs: add metrics documentation * fix: metrics endpoint conditional check * feat: metrics endpoint basic auth * fix: make metrics-auth-enabled default false * fix: go fmt helpers.gen.go * fix: add metric-related env vars to envparsing.sh * fix: metrics docs * fix: metrics related stuff in envparsing.sh * fix: metrics docs * chore: metrics docs wording * fix: metrics stuff in envparsing? * bump otel versions --------- Co-authored-by: Tsuribori <user@acertaindebian> Co-authored-by: Tsuribori <none@example.org> Co-authored-by: tsmethurst <tobi.smethurst@protonmail.com>
		
			
				
	
	
		
			527 lines
		
	
	
	
		
			13 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			527 lines
		
	
	
	
		
			13 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // Copyright 2020 The Prometheus Authors
 | |
| // Licensed under the Apache License, Version 2.0 (the "License");
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| // you may not use this file except in compliance with the License.
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| // You may obtain a copy of the License at
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| //
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| // http://www.apache.org/licenses/LICENSE-2.0
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| //
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| // Unless required by applicable law or agreed to in writing, software
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| // distributed under the License is distributed on an "AS IS" BASIS,
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| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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| // See the License for the specific language governing permissions and
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| // limitations under the License.
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| 
 | |
| package expfmt
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| 
 | |
| import (
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| 	"bufio"
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| 	"bytes"
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| 	"fmt"
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| 	"io"
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| 	"math"
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| 	"strconv"
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| 	"strings"
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| 
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| 	"github.com/prometheus/common/model"
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| 
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| 	dto "github.com/prometheus/client_model/go"
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| )
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| 
 | |
| // MetricFamilyToOpenMetrics converts a MetricFamily proto message into the
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| // OpenMetrics text format and writes the resulting lines to 'out'. It returns
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| // the number of bytes written and any error encountered. The output will have
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| // the same order as the input, no further sorting is performed. Furthermore,
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| // this function assumes the input is already sanitized and does not perform any
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| // sanity checks. If the input contains duplicate metrics or invalid metric or
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| // label names, the conversion will result in invalid text format output.
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| //
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| // This function fulfills the type 'expfmt.encoder'.
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| //
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| // Note that OpenMetrics requires a final `# EOF` line. Since this function acts
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| // on individual metric families, it is the responsibility of the caller to
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| // append this line to 'out' once all metric families have been written.
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| // Conveniently, this can be done by calling FinalizeOpenMetrics.
 | |
| //
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| // The output should be fully OpenMetrics compliant. However, there are a few
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| // missing features and peculiarities to avoid complications when switching from
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| // Prometheus to OpenMetrics or vice versa:
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| //
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| //   - Counters are expected to have the `_total` suffix in their metric name. In
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| //     the output, the suffix will be truncated from the `# TYPE` and `# HELP`
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| //     line. A counter with a missing `_total` suffix is not an error. However,
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| //     its type will be set to `unknown` in that case to avoid invalid OpenMetrics
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| //     output.
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| //
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| //   - No support for the following (optional) features: `# UNIT` line, `_created`
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| //     line, info type, stateset type, gaugehistogram type.
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| //
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| //   - The size of exemplar labels is not checked (i.e. it's possible to create
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| //     exemplars that are larger than allowed by the OpenMetrics specification).
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| //
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| //   - The value of Counters is not checked. (OpenMetrics doesn't allow counters
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| //     with a `NaN` value.)
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| func MetricFamilyToOpenMetrics(out io.Writer, in *dto.MetricFamily) (written int, err error) {
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| 	name := in.GetName()
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| 	if name == "" {
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| 		return 0, fmt.Errorf("MetricFamily has no name: %s", in)
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| 	}
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| 
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| 	// Try the interface upgrade. If it doesn't work, we'll use a
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| 	// bufio.Writer from the sync.Pool.
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| 	w, ok := out.(enhancedWriter)
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| 	if !ok {
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| 		b := bufPool.Get().(*bufio.Writer)
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| 		b.Reset(out)
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| 		w = b
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| 		defer func() {
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| 			bErr := b.Flush()
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| 			if err == nil {
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| 				err = bErr
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| 			}
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| 			bufPool.Put(b)
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| 		}()
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| 	}
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| 
 | |
| 	var (
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| 		n          int
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| 		metricType = in.GetType()
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| 		shortName  = name
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| 	)
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| 	if metricType == dto.MetricType_COUNTER && strings.HasSuffix(shortName, "_total") {
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| 		shortName = name[:len(name)-6]
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| 	}
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| 
 | |
| 	// Comments, first HELP, then TYPE.
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| 	if in.Help != nil {
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| 		n, err = w.WriteString("# HELP ")
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| 		written += n
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| 		if err != nil {
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| 			return
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| 		}
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| 		n, err = w.WriteString(shortName)
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| 		written += n
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| 		if err != nil {
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| 			return
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| 		}
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| 		err = w.WriteByte(' ')
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| 		written++
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| 		if err != nil {
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| 			return
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| 		}
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| 		n, err = writeEscapedString(w, *in.Help, true)
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| 		written += n
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| 		if err != nil {
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| 			return
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| 		}
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| 		err = w.WriteByte('\n')
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| 		written++
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| 		if err != nil {
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| 			return
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| 		}
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| 	}
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| 	n, err = w.WriteString("# TYPE ")
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| 	written += n
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| 	if err != nil {
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| 		return
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| 	}
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| 	n, err = w.WriteString(shortName)
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| 	written += n
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| 	if err != nil {
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| 		return
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| 	}
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| 	switch metricType {
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| 	case dto.MetricType_COUNTER:
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| 		if strings.HasSuffix(name, "_total") {
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| 			n, err = w.WriteString(" counter\n")
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| 		} else {
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| 			n, err = w.WriteString(" unknown\n")
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| 		}
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| 	case dto.MetricType_GAUGE:
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| 		n, err = w.WriteString(" gauge\n")
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| 	case dto.MetricType_SUMMARY:
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| 		n, err = w.WriteString(" summary\n")
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| 	case dto.MetricType_UNTYPED:
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| 		n, err = w.WriteString(" unknown\n")
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| 	case dto.MetricType_HISTOGRAM:
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| 		n, err = w.WriteString(" histogram\n")
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| 	default:
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| 		return written, fmt.Errorf("unknown metric type %s", metricType.String())
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| 	}
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| 	written += n
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| 	if err != nil {
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| 		return
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| 	}
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| 
 | |
| 	// Finally the samples, one line for each.
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| 	for _, metric := range in.Metric {
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| 		switch metricType {
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| 		case dto.MetricType_COUNTER:
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| 			if metric.Counter == nil {
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| 				return written, fmt.Errorf(
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| 					"expected counter in metric %s %s", name, metric,
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| 				)
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| 			}
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| 			// Note that we have ensured above that either the name
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| 			// ends on `_total` or that the rendered type is
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| 			// `unknown`. Therefore, no `_total` must be added here.
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| 			n, err = writeOpenMetricsSample(
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| 				w, name, "", metric, "", 0,
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| 				metric.Counter.GetValue(), 0, false,
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| 				metric.Counter.Exemplar,
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| 			)
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| 		case dto.MetricType_GAUGE:
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| 			if metric.Gauge == nil {
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| 				return written, fmt.Errorf(
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| 					"expected gauge in metric %s %s", name, metric,
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| 				)
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| 			}
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| 			n, err = writeOpenMetricsSample(
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| 				w, name, "", metric, "", 0,
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| 				metric.Gauge.GetValue(), 0, false,
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| 				nil,
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| 			)
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| 		case dto.MetricType_UNTYPED:
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| 			if metric.Untyped == nil {
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| 				return written, fmt.Errorf(
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| 					"expected untyped in metric %s %s", name, metric,
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| 				)
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| 			}
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| 			n, err = writeOpenMetricsSample(
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| 				w, name, "", metric, "", 0,
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| 				metric.Untyped.GetValue(), 0, false,
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| 				nil,
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| 			)
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| 		case dto.MetricType_SUMMARY:
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| 			if metric.Summary == nil {
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| 				return written, fmt.Errorf(
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| 					"expected summary in metric %s %s", name, metric,
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| 				)
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| 			}
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| 			for _, q := range metric.Summary.Quantile {
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| 				n, err = writeOpenMetricsSample(
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| 					w, name, "", metric,
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| 					model.QuantileLabel, q.GetQuantile(),
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| 					q.GetValue(), 0, false,
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| 					nil,
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| 				)
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| 				written += n
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| 				if err != nil {
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| 					return
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| 				}
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| 			}
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| 			n, err = writeOpenMetricsSample(
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| 				w, name, "_sum", metric, "", 0,
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| 				metric.Summary.GetSampleSum(), 0, false,
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| 				nil,
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| 			)
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| 			written += n
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| 			if err != nil {
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| 				return
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| 			}
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| 			n, err = writeOpenMetricsSample(
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| 				w, name, "_count", metric, "", 0,
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| 				0, metric.Summary.GetSampleCount(), true,
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| 				nil,
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| 			)
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| 		case dto.MetricType_HISTOGRAM:
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| 			if metric.Histogram == nil {
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| 				return written, fmt.Errorf(
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| 					"expected histogram in metric %s %s", name, metric,
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| 				)
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| 			}
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| 			infSeen := false
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| 			for _, b := range metric.Histogram.Bucket {
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| 				n, err = writeOpenMetricsSample(
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| 					w, name, "_bucket", metric,
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| 					model.BucketLabel, b.GetUpperBound(),
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| 					0, b.GetCumulativeCount(), true,
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| 					b.Exemplar,
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| 				)
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| 				written += n
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| 				if err != nil {
 | |
| 					return
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| 				}
 | |
| 				if math.IsInf(b.GetUpperBound(), +1) {
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| 					infSeen = true
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| 				}
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| 			}
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| 			if !infSeen {
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| 				n, err = writeOpenMetricsSample(
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| 					w, name, "_bucket", metric,
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| 					model.BucketLabel, math.Inf(+1),
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| 					0, metric.Histogram.GetSampleCount(), true,
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| 					nil,
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| 				)
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| 				written += n
 | |
| 				if err != nil {
 | |
| 					return
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| 				}
 | |
| 			}
 | |
| 			n, err = writeOpenMetricsSample(
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| 				w, name, "_sum", metric, "", 0,
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| 				metric.Histogram.GetSampleSum(), 0, false,
 | |
| 				nil,
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| 			)
 | |
| 			written += n
 | |
| 			if err != nil {
 | |
| 				return
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| 			}
 | |
| 			n, err = writeOpenMetricsSample(
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| 				w, name, "_count", metric, "", 0,
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| 				0, metric.Histogram.GetSampleCount(), true,
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| 				nil,
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| 			)
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| 		default:
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| 			return written, fmt.Errorf(
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| 				"unexpected type in metric %s %s", name, metric,
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| 			)
 | |
| 		}
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return
 | |
| 		}
 | |
| 	}
 | |
| 	return
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| }
 | |
| 
 | |
| // FinalizeOpenMetrics writes the final `# EOF\n` line required by OpenMetrics.
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| func FinalizeOpenMetrics(w io.Writer) (written int, err error) {
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| 	return w.Write([]byte("# EOF\n"))
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| }
 | |
| 
 | |
| // writeOpenMetricsSample writes a single sample in OpenMetrics text format to
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| // w, given the metric name, the metric proto message itself, optionally an
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| // additional label name with a float64 value (use empty string as label name if
 | |
| // not required), the value (optionally as float64 or uint64, determined by
 | |
| // useIntValue), and optionally an exemplar (use nil if not required). The
 | |
| // function returns the number of bytes written and any error encountered.
 | |
| func writeOpenMetricsSample(
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| 	w enhancedWriter,
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| 	name, suffix string,
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| 	metric *dto.Metric,
 | |
| 	additionalLabelName string, additionalLabelValue float64,
 | |
| 	floatValue float64, intValue uint64, useIntValue bool,
 | |
| 	exemplar *dto.Exemplar,
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| ) (int, error) {
 | |
| 	var written int
 | |
| 	n, err := w.WriteString(name)
 | |
| 	written += n
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	if suffix != "" {
 | |
| 		n, err = w.WriteString(suffix)
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 	}
 | |
| 	n, err = writeOpenMetricsLabelPairs(
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| 		w, metric.Label, additionalLabelName, additionalLabelValue,
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| 	)
 | |
| 	written += n
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	err = w.WriteByte(' ')
 | |
| 	written++
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	if useIntValue {
 | |
| 		n, err = writeUint(w, intValue)
 | |
| 	} else {
 | |
| 		n, err = writeOpenMetricsFloat(w, floatValue)
 | |
| 	}
 | |
| 	written += n
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	if metric.TimestampMs != nil {
 | |
| 		err = w.WriteByte(' ')
 | |
| 		written++
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		// TODO(beorn7): Format this directly without converting to a float first.
 | |
| 		n, err = writeOpenMetricsFloat(w, float64(*metric.TimestampMs)/1000)
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 	}
 | |
| 	if exemplar != nil {
 | |
| 		n, err = writeExemplar(w, exemplar)
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 	}
 | |
| 	err = w.WriteByte('\n')
 | |
| 	written++
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	return written, nil
 | |
| }
 | |
| 
 | |
| // writeOpenMetricsLabelPairs works like writeOpenMetrics but formats the float
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| // in OpenMetrics style.
 | |
| func writeOpenMetricsLabelPairs(
 | |
| 	w enhancedWriter,
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| 	in []*dto.LabelPair,
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| 	additionalLabelName string, additionalLabelValue float64,
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| ) (int, error) {
 | |
| 	if len(in) == 0 && additionalLabelName == "" {
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| 		return 0, nil
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| 	}
 | |
| 	var (
 | |
| 		written   int
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| 		separator byte = '{'
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| 	)
 | |
| 	for _, lp := range in {
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| 		err := w.WriteByte(separator)
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| 		written++
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		n, err := w.WriteString(lp.GetName())
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		n, err = w.WriteString(`="`)
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| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		n, err = writeEscapedString(w, lp.GetValue(), true)
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		err = w.WriteByte('"')
 | |
| 		written++
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		separator = ','
 | |
| 	}
 | |
| 	if additionalLabelName != "" {
 | |
| 		err := w.WriteByte(separator)
 | |
| 		written++
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		n, err := w.WriteString(additionalLabelName)
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		n, err = w.WriteString(`="`)
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		n, err = writeOpenMetricsFloat(w, additionalLabelValue)
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		err = w.WriteByte('"')
 | |
| 		written++
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 	}
 | |
| 	err := w.WriteByte('}')
 | |
| 	written++
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	return written, nil
 | |
| }
 | |
| 
 | |
| // writeExemplar writes the provided exemplar in OpenMetrics format to w. The
 | |
| // function returns the number of bytes written and any error encountered.
 | |
| func writeExemplar(w enhancedWriter, e *dto.Exemplar) (int, error) {
 | |
| 	written := 0
 | |
| 	n, err := w.WriteString(" # ")
 | |
| 	written += n
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	n, err = writeOpenMetricsLabelPairs(w, e.Label, "", 0)
 | |
| 	written += n
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	err = w.WriteByte(' ')
 | |
| 	written++
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	n, err = writeOpenMetricsFloat(w, e.GetValue())
 | |
| 	written += n
 | |
| 	if err != nil {
 | |
| 		return written, err
 | |
| 	}
 | |
| 	if e.Timestamp != nil {
 | |
| 		err = w.WriteByte(' ')
 | |
| 		written++
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		err = (*e).Timestamp.CheckValid()
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 		ts := (*e).Timestamp.AsTime()
 | |
| 		// TODO(beorn7): Format this directly from components of ts to
 | |
| 		// avoid overflow/underflow and precision issues of the float
 | |
| 		// conversion.
 | |
| 		n, err = writeOpenMetricsFloat(w, float64(ts.UnixNano())/1e9)
 | |
| 		written += n
 | |
| 		if err != nil {
 | |
| 			return written, err
 | |
| 		}
 | |
| 	}
 | |
| 	return written, nil
 | |
| }
 | |
| 
 | |
| // writeOpenMetricsFloat works like writeFloat but appends ".0" if the resulting
 | |
| // number would otherwise contain neither a "." nor an "e".
 | |
| func writeOpenMetricsFloat(w enhancedWriter, f float64) (int, error) {
 | |
| 	switch {
 | |
| 	case f == 1:
 | |
| 		return w.WriteString("1.0")
 | |
| 	case f == 0:
 | |
| 		return w.WriteString("0.0")
 | |
| 	case f == -1:
 | |
| 		return w.WriteString("-1.0")
 | |
| 	case math.IsNaN(f):
 | |
| 		return w.WriteString("NaN")
 | |
| 	case math.IsInf(f, +1):
 | |
| 		return w.WriteString("+Inf")
 | |
| 	case math.IsInf(f, -1):
 | |
| 		return w.WriteString("-Inf")
 | |
| 	default:
 | |
| 		bp := numBufPool.Get().(*[]byte)
 | |
| 		*bp = strconv.AppendFloat((*bp)[:0], f, 'g', -1, 64)
 | |
| 		if !bytes.ContainsAny(*bp, "e.") {
 | |
| 			*bp = append(*bp, '.', '0')
 | |
| 		}
 | |
| 		written, err := w.Write(*bp)
 | |
| 		numBufPool.Put(bp)
 | |
| 		return written, err
 | |
| 	}
 | |
| }
 | |
| 
 | |
| // writeUint is like writeInt just for uint64.
 | |
| func writeUint(w enhancedWriter, u uint64) (int, error) {
 | |
| 	bp := numBufPool.Get().(*[]byte)
 | |
| 	*bp = strconv.AppendUint((*bp)[:0], u, 10)
 | |
| 	written, err := w.Write(*bp)
 | |
| 	numBufPool.Put(bp)
 | |
| 	return written, err
 | |
| }
 |