Merge pull request 'Update workflows' (#109) from atolstikhin/micro-meter-prometheus:v3 into v3

Reviewed-on: #109

.gitea/workflows/job_lint.yml

@@ -0,0 +1,29 @@
+name: lint
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches:
+    - master
+    - v3
+    - v4
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable' 
+    - name: setup deps
+      run: go get -v ./...
+    - name: run lint
+      uses: https://github.com/golangci/golangci-lint-action@v6
+      with:
+        version: 'latest'

.gitea/workflows/job_test.yml

@@ -0,0 +1,34 @@
+name: test
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches:
+    - master
+    - v3
+    - v4
+  push:
+    branches:
+    - master
+    - v3
+    - v4
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable'
+    - name: setup deps
+      run: go get -v ./...
+    - name: run test
+      env:
+        INTEGRATION_TESTS: yes
+      run: go test -mod readonly -v ./...

.gitea/workflows/job_tests.yml

@@ -0,0 +1,53 @@
+name: test
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches:
+    - master
+    - v3
+    - v4
+  push:
+    branches:
+    - master
+    - v3
+    - v4
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: checkout tests
+      uses: actions/checkout@v4
+      with:
+        ref: master
+        filter: 'blob:none'
+        repository: unistack-org/micro-tests
+        path: micro-tests
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable'
+    - name: setup go work
+      env:
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
+      run: |
+        go work init
+        go work use .
+        go work use micro-tests
+    - name: setup deps
+      env:
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
+      run: go get -v ./...
+    - name: run tests
+      env:
+        INTEGRATION_TESTS: yes
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
+      run: |
+        cd micro-tests
+        go test -mod readonly -v ./... || true

.github/dependabot.yml

@@ -1,19 +0,0 @@
-# To get started with Dependabot version updates, you'll need to specify which
-# package ecosystems to update and where the package manifests are located.
-# Please see the documentation for all configuration options:
-# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
-
-version: 2
-updates:
-
-  # Maintain dependencies for GitHub Actions
-  - package-ecosystem: "github-actions"
-    directory: "/"
-    schedule:
-      interval: "daily"
-
-  # Maintain dependencies for Golang
-  - package-ecosystem: "gomod"
-    directory: "/"
-    schedule:
-      interval: "daily"

.github/workflows/autoapprove.yml

@@ -1,20 +0,0 @@
-name: "autoapprove"
-
-on:
-  pull_request_target:
-    types: [assigned, opened, synchronize, reopened]
-
-permissions:
-  pull-requests: write
-  contents: write
-
-jobs:
-  autoapprove:
-    runs-on: ubuntu-latest
-    steps:
-      - name: approve
-        uses: hmarr/auto-approve-action@v3
-        if: github.actor == 'vtolstov' || github.actor == 'dependabot[bot]'
-        id: approve
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/automerge.yml

@@ -1,21 +0,0 @@
-name: "automerge"
-
-on:
-  pull_request_target:
-    types: [assigned, opened, synchronize, reopened]
-
-permissions:
-  pull-requests: write
-  contents: write
-
-jobs:
-  automerge:
-    runs-on: ubuntu-latest
-    if: github.actor == 'vtolstov'
-    steps:
-      - name: merge
-        id: merge
-        run: gh pr merge --auto --merge "$PR_URL"
-        env:
-          PR_URL: ${{github.event.pull_request.html_url}}
-          GITHUB_TOKEN: ${{secrets.TOKEN}}

.github/workflows/build.yml

@@ -1,47 +0,0 @@
-name: build
-on:
- push:
-    branches:
-    - master
-    - v3
-jobs:
-  test:
-    name: test
-    runs-on: ubuntu-latest
-    steps:
-    - name: setup
-      uses: actions/setup-go@v3
-      with:
-        go-version: 1.17
-    - name: checkout
-      uses: actions/checkout@v3
-    - name: cache
-      uses: actions/cache@v3
-      with:
-        path: ~/go/pkg/mod
-        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
-        restore-keys: ${{ runner.os }}-go-
-    - name: deps
-      run: go get -v -t -d ./...
-    - name: test
-      env:
-        INTEGRATION_TESTS: yes
-      run: go test -mod readonly -v ./...
-  lint:
-    name: lint
-    runs-on: ubuntu-latest
-    steps:
-      - name: checkout
-        uses: actions/checkout@v3
-      - name: lint
-        uses: golangci/golangci-lint-action@v3.4.0
-        continue-on-error: true
-        with:
-          # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
-          version: v1.30
-          # Optional: working directory, useful for monorepos
-          # working-directory: somedir
-          # Optional: golangci-lint command line arguments.
-          # args: --issues-exit-code=0
-          # Optional: show only new issues if it's a pull request. The default value is `false`.
-          # only-new-issues: true

.github/workflows/codeql-analysis.yml

@@ -1,78 +0,0 @@
-# For most projects, this workflow file will not need changing; you simply need
-# to commit it to your repository.
-#
-# You may wish to alter this file to override the set of languages analyzed,
-# or to provide custom queries or build logic.
-#
-# ******** NOTE ********
-# We have attempted to detect the languages in your repository. Please check
-# the `language` matrix defined below to confirm you have the correct set of
-# supported CodeQL languages.
-#
-name: "codeql"
-
-on:
-  workflow_run:
-    workflows: ["prbuild"]
-    types:
-      - completed
-  push:
-    branches: [ master, v3 ]
-  pull_request:
-    # The branches below must be a subset of the branches above
-    branches: [ master, v3 ]
-  schedule:
-    - cron: '34 1 * * 0'
-
-jobs:
-  analyze:
-    name: analyze
-    runs-on: ubuntu-latest
-    permissions:
-      actions: read
-      contents: read
-      security-events: write
-
-    strategy:
-      fail-fast: false
-      matrix:
-        language: [ 'go' ]
-        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python' ]
-        # Learn more:
-        # https://docs.github.com/en/free-pro-team@latest/github/finding-security-vulnerabilities-and-errors-in-your-code/configuring-code-scanning#changing-the-languages-that-are-analyzed
-
-    steps:
-    - name: checkout
-      uses: actions/checkout@v3
-    - name: setup
-      uses: actions/setup-go@v3
-      with:
-        go-version: 1.17
-    # Initializes the CodeQL tools for scanning.
-    - name: init
-      uses: github/codeql-action/init@v2
-      with:
-        languages: ${{ matrix.language }}
-        # If you wish to specify custom queries, you can do so here or in a config file.
-        # By default, queries listed here will override any specified in a config file.
-        # Prefix the list here with "+" to use these queries and those in the config file.
-        # queries: ./path/to/local/query, your-org/your-repo/queries@main
-
-    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
-    # If this step fails, then you should remove it and run the build manually (see below)
-    - name: autobuild
-      uses: github/codeql-action/autobuild@v2
-
-    # ℹ️ Command-line programs to run using the OS shell.
-    # 📚 https://git.io/JvXDl
-
-    # ✏️ If the Autobuild fails above, remove it and uncomment the following three lines
-    #    and modify them (or add more) to build your code if your project
-    #    uses a compiled language
-
-    #- run: |
-    #   make bootstrap
-    #   make release
-
-    - name: analyze
-      uses: github/codeql-action/analyze@v2

.github/workflows/dependabot-automerge.yml

@@ -1,27 +0,0 @@
-name: "dependabot-automerge"
-
-on:
-  pull_request_target:
-    types: [assigned, opened, synchronize, reopened]
-
-permissions:
-  pull-requests: write
-  contents: write
-
-jobs:
-  automerge:
-    runs-on: ubuntu-latest
-    if: github.actor == 'dependabot[bot]'
-    steps:
-      - name: metadata
-        id: metadata
-        uses: dependabot/fetch-metadata@v1.3.6
-        with:
-          github-token: "${{ secrets.TOKEN }}"
-      - name: merge
-        id: merge
-        if: ${{contains(steps.metadata.outputs.dependency-names, 'go.unistack.org')}}
-        run: gh pr merge --auto --merge "$PR_URL"
-        env:
-          PR_URL: ${{github.event.pull_request.html_url}}
-          GITHUB_TOKEN: ${{secrets.TOKEN}}

.github/workflows/pr.yml

@@ -1,47 +0,0 @@
-name: prbuild
-on:
-  pull_request:
-    branches:
-    - master
-    - v3
-jobs:
-  test:
-    name: test
-    runs-on: ubuntu-latest
-    steps:
-    - name: setup
-      uses: actions/setup-go@v3
-      with:
-        go-version: 1.17
-    - name: checkout
-      uses: actions/checkout@v3
-    - name: cache
-      uses: actions/cache@v3
-      with:
-        path: ~/go/pkg/mod
-        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
-        restore-keys: ${{ runner.os }}-go-
-    - name: deps
-      run: go get -v -t -d ./...
-    - name: test
-      env:
-        INTEGRATION_TESTS: yes
-      run: go test -mod readonly -v ./...
-  lint:
-    name: lint
-    runs-on: ubuntu-latest
-    steps:
-      - name: checkout
-        uses: actions/checkout@v3
-      - name: lint
-        uses: golangci/golangci-lint-action@v3.4.0
-        continue-on-error: true
-        with:
-          # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
-          version: v1.30
-          # Optional: working directory, useful for monorepos
-          # working-directory: somedir
-          # Optional: golangci-lint command line arguments.
-          # args: --issues-exit-code=0
-          # Optional: show only new issues if it's a pull request. The default value is `false`.
-          # only-new-issues: true

.golangci.yml

@@ -0,0 +1,5 @@
+run:
+  concurrency: 8
+  deadline: 5m
+  issues-exit-code: 1
+  tests: true

counter.go

@@ -11,55 +11,57 @@ import (
 type prometheusCounter struct {
 	name string
 	c    *dto.Metric
+	n    float64
 }
 
 func (c *prometheusCounter) Add(n int) {
-	addFloat64(c.c.Gauge.Value, float64(n))
+	addFloat64(&(c.n), float64(n))
 }
 
 func (c *prometheusCounter) Dec() {
-	addFloat64(c.c.Gauge.Value, float64(-1))
+	addFloat64(&(c.n), float64(-1))
 }
 
 func (c *prometheusCounter) Inc() {
-	addFloat64(c.c.Gauge.Value, float64(1))
+	addFloat64(&(c.n), float64(1))
 }
 
 func (c *prometheusCounter) Get() uint64 {
-	return uint64(getFloat64(c.c.Gauge.Value))
+	return uint64(getFloat64(&(c.n)))
 }
 
 func (c *prometheusCounter) Set(n uint64) {
-	setFloat64(c.c.Gauge.Value, math.Float64frombits(n))
+	setFloat64(&(c.n), math.Float64frombits(n))
 }
 
 type prometheusFloatCounter struct {
 	name string
 	c    *dto.Metric
+	n    float64
 }
 
 func (c *prometheusFloatCounter) Add(n float64) {
-	addFloat64(c.c.Gauge.Value, n)
+	addFloat64(&(c.n), n)
 }
 
 func (c *prometheusFloatCounter) Dec() {
-	addFloat64(c.c.Gauge.Value, float64(-1))
+	addFloat64(&(c.n), float64(-1))
 }
 
 func (c *prometheusFloatCounter) Inc() {
-	addFloat64(c.c.Gauge.Value, float64(1))
+	addFloat64(&(c.n), float64(1))
 }
 
 func (c *prometheusFloatCounter) Get() float64 {
-	return getFloat64(c.c.Gauge.Value)
+	return getFloat64(&(c.n))
 }
 
 func (c *prometheusFloatCounter) Set(n float64) {
-	setFloat64(c.c.Gauge.Value, n)
+	setFloat64(&(c.n), n)
 }
 
 func (c *prometheusFloatCounter) Sub(n float64) {
-	addFloat64(c.c.Gauge.Value, -n)
+	addFloat64(&(c.n), -n)
 }
 
 func setFloat64(_addr *float64, value float64) float64 {

gauge.go

@@ -5,8 +5,9 @@ import dto "github.com/prometheus/client_model/go"
 type prometheusGauge struct {
 	name string
 	c    *dto.Metric
+	n    float64
 }
 
-func (c prometheusGauge) Get() float64 {
-	return getFloat64(c.c.Gauge.Value)
+func (c *prometheusGauge) Get() float64 {
+	return getFloat64(&(c.n))
 }

prometheus.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"regexp"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/prometheus/client_golang/prometheus"
@@ -53,82 +54,83 @@ func (m *prometheusMeter) Counter(name string, labels ...string) meter.Counter {
 	clabels := meter.BuildLabels(append(m.opts.Labels, labels...)...)
 	h := newHash(name, clabels)
 	m.mu.Lock()
-	mc, ok := m.counter[h]
+	c, ok := m.counter[h]
+	// fmt.Printf("counter name %s hash %v labels %v\n", name, h, labels)
 	m.mu.Unlock()
 	if !ok {
-		var v float64
-		mc = &prometheusCounter{
+		var n float64
+		c = &prometheusCounter{
 			name: name,
 			c: &dto.Metric{
-				Gauge: &dto.Gauge{Value: &v},
+				Gauge: &dto.Gauge{Value: &n},
 				Label: labelMetric(clabels),
 			},
 		}
 		m.mu.Lock()
-		m.counter[h] = mc
+		m.counter[h] = c
 		m.mu.Unlock()
 	}
-	return mc
+	return c
 }
 
 func (m *prometheusMeter) FloatCounter(name string, labels ...string) meter.FloatCounter {
 	clabels := meter.BuildLabels(append(m.opts.Labels, labels...)...)
 	h := newHash(name, clabels)
 	m.mu.Lock()
-	mc, ok := m.floatCounter[h]
+	c, ok := m.floatCounter[h]
 	m.mu.Unlock()
 	if !ok {
-		var v float64
-		mc = &prometheusFloatCounter{
+		var n float64
+		c = &prometheusFloatCounter{
 			name: name,
 			c: &dto.Metric{
-				Gauge: &dto.Gauge{Value: &v},
+				Gauge: &dto.Gauge{Value: &n},
 				Label: labelMetric(clabels),
 			},
 		}
 		m.mu.Lock()
-		m.floatCounter[h] = mc
+		m.floatCounter[h] = c
 		m.mu.Unlock()
 	}
-	return mc
+	return c
 }
 
 func (m *prometheusMeter) Gauge(name string, fn func() float64, labels ...string) meter.Gauge {
 	clabels := meter.BuildLabels(append(m.opts.Labels, labels...)...)
 	h := newHash(name, clabels)
 	m.mu.Lock()
-	mc, ok := m.gauge[h]
+	c, ok := m.gauge[h]
 	m.mu.Unlock()
 	if !ok {
-		var v float64
-		mc = &prometheusGauge{
+		var n float64
+		c = &prometheusGauge{
 			name: name,
 			c: &dto.Metric{
-				Gauge: &dto.Gauge{Value: &v},
+				Gauge: &dto.Gauge{Value: &n},
 				Label: labelMetric(clabels),
 			},
 		}
 		m.mu.Lock()
-		m.gauge[h] = mc
+		m.gauge[h] = c
 		m.mu.Unlock()
 	}
-	return mc
+	return c
 }
 
 func (m *prometheusMeter) Histogram(name string, labels ...string) meter.Histogram {
 	clabels := meter.BuildLabels(append(m.opts.Labels, labels...)...)
 	h := newHash(name, clabels)
 	m.mu.Lock()
-	mc, ok := m.histogram[h]
+	c, ok := m.histogram[h]
 	m.mu.Unlock()
 	if !ok {
-		var c uint64
+		var n uint64
 		var s float64
 		buckets := make([]float64, len(prometheus.DefBuckets))
 		copy(buckets, prometheus.DefBuckets)
 		mdto := &dto.Metric{
 			Histogram: &dto.Histogram{
-				SampleCount:      &c,
+				SampleCount:      &n,
 				SampleSum:        &s,
 				CreatedTimestamp: timestamppb.Now(),
 				Bucket:           make([]*dto.Bucket, len(buckets)),
@@ -139,31 +141,31 @@ func (m *prometheusMeter) Histogram(name string, labels ...string) meter.Histogr
 			var cc uint64
 			mdto.Histogram.Bucket[idx] = &dto.Bucket{CumulativeCount: &cc, UpperBound: &b}
 		}
-		mc = &prometheusHistogram{
+		c = &prometheusHistogram{
 			name: name,
 			c:    mdto,
 		}
 		m.mu.Lock()
-		m.histogram[h] = mc
+		m.histogram[h] = c
 		m.mu.Unlock()
 	}
-	return mc
+	return c
 }
 
 func (m *prometheusMeter) Summary(name string, labels ...string) meter.Summary {
 	clabels := meter.BuildLabels(append(m.opts.Labels, labels...)...)
 	h := newHash(name, clabels)
 	m.mu.Lock()
-	mc, ok := m.summary[h]
+	c, ok := m.summary[h]
 	m.mu.Unlock()
 	if !ok {
-		var c uint64
+		var n uint64
 		var s float64
-		mc = &prometheusSummary{
+		c = &prometheusSummary{
 			name: name,
 			c: &dto.Metric{
 				Summary: &dto.Summary{
-					SampleCount:      &c,
+					SampleCount:      &n,
 					SampleSum:        &s,
 					CreatedTimestamp: timestamppb.Now(),
 				},
@@ -171,36 +173,36 @@ func (m *prometheusMeter) Summary(name string, labels ...string) meter.Summary {
 			},
 		}
 		m.mu.Lock()
-		m.summary[h] = mc
+		m.summary[h] = c
 		m.mu.Unlock()
 	}
-	return mc
+	return c
 }
 
 func (m *prometheusMeter) SummaryExt(name string, window time.Duration, quantiles []float64, labels ...string) meter.Summary {
 	clabels := meter.BuildLabels(append(m.opts.Labels, labels...)...)
 	h := newHash(name, clabels)
 	m.mu.Lock()
-	mc, ok := m.summary[h]
+	c, ok := m.summary[h]
 	m.mu.Lock()
 	if !ok {
-		var c uint64
+		var n uint64
 		var s float64
-		mc = &prometheusSummary{
+		c = &prometheusSummary{
 			name: name,
 			c: &dto.Metric{
 				Summary: &dto.Summary{
-					SampleCount: &c,
+					SampleCount: &n,
 					SampleSum:   &s,
 				},
 				Label: labelMetric(clabels),
 			},
 		}
 		m.mu.Lock()
-		m.summary[h] = mc
+		m.summary[h] = c
 		m.mu.Unlock()
 	}
-	return mc
+	return c
 }
 
 func (m *prometheusMeter) Init(opts ...meter.Option) error {
@@ -238,27 +240,33 @@ func (m *prometheusMeter) Write(w io.Writer, opts ...meter.Option) error {
 
 	m.mu.Lock()
 
-	for _, c := range m.counter {
+	for _, mc := range m.counter {
 		mf := m.mfPool.Get()
-		mf.Name = &c.name
+		mf.Name = &mc.name
 		mf.Type = dto.MetricType_GAUGE.Enum()
-		mf.Metric = append(mf.Metric, c.c)
+		n := getFloat64(&(mc.n))
+		mc.c.Gauge.Value = &n
+		mf.Metric = append(mf.Metric, mc.c)
 		mfs = append(mfs, mf)
 	}
 
-	for _, c := range m.floatCounter {
+	for _, mc := range m.floatCounter {
 		mf := m.mfPool.Get()
-		mf.Name = &c.name
+		mf.Name = &mc.name
 		mf.Type = dto.MetricType_GAUGE.Enum()
-		mf.Metric = append(mf.Metric, c.c)
+		n := getFloat64(&(mc.n))
+		mc.c.Gauge.Value = &n
+		mf.Metric = append(mf.Metric, mc.c)
 		mfs = append(mfs, mf)
 	}
 
-	for _, c := range m.gauge {
+	for _, mc := range m.gauge {
 		mf := m.mfPool.Get()
-		mf.Name = &c.name
+		mf.Name = &mc.name
 		mf.Type = dto.MetricType_GAUGE.Enum()
-		mf.Metric = append(mf.Metric, c.c)
+		n := getFloat64(&(mc.n))
+		mc.c.Gauge.Value = &n
+		mf.Metric = append(mf.Metric, mc.c)
 		mfs = append(mfs, mf)
 	}
 
@@ -270,11 +278,15 @@ func (m *prometheusMeter) Write(w io.Writer, opts ...meter.Option) error {
 		mfs = append(mfs, mf)
 	}
 
-	for _, c := range m.summary {
+	for _, mc := range m.summary {
 		mf := m.mfPool.Get()
-		mf.Name = &c.name
+		mf.Name = &mc.name
 		mf.Type = dto.MetricType_SUMMARY.Enum()
-		mf.Metric = append(mf.Metric, c.c)
+		sc := atomic.LoadUint64(&(mc.sampleCount))
+		mc.c.Summary.SampleCount = &sc
+		ss := getFloat64(&(mc.SampleSum))
+		mc.c.Summary.SampleSum = &ss
+		mf.Metric = append(mf.Metric, mc.c)
 		mfs = append(mfs, mf)
 	}
 

prometheus_test.go

@@ -15,11 +15,25 @@ import (
 )
 
 func TestHash(t *testing.T) {
-	t.Skip()
-	h1 := newHash("micro_server_request_total", []string{"code", "16", "endpoint", "/clientprofile.ClientProfileService/GetClientProfile", "status", "failure"})
-	h2 := newHash("micro_server_request_total", []string{"code", "16", "endpoint", "/clientproduct.ClientProductService/GetDepositProducts", "status", "failure"})
-	h3 := newHash("micro_server_request_total", []string{"code", "16", "endpoint", "/operationsinfo.OperationsInfoService/GetOperations", "status", "failure"})
-	t.Logf("h1: %v\nh2: %v\nh3: %v\n", h1, h2, h3)
+	m := NewMeter() // meter.Labels("test_key", "test_val"))
+
+	buf := bytes.NewBuffer(nil)
+
+	for i := 0; i < 100000; i++ {
+		go func() {
+			m.Counter("micro_server_request_total", "code", "16",
+				"endpoint", "/clientprofile.ClientProfileService/GetClientProfile",
+				"status", "failure").Inc()
+			m.Counter("micro_server_request_total", "code", "16",
+				"endpoint", "/clientproduct.ClientProductService/GetDepositProducts",
+				"status", "failure").Inc()
+			m.Counter("micro_server_request_total", "code", "16",
+				"endpoint", "/operationsinfo.OperationsInfoService/GetOperations",
+				"status", "failure").Inc()
+		}()
+	}
+	_ = m.Write(buf)
+	t.Logf("h1: %s\n", buf.Bytes())
 }
 
 func TestHistogram(t *testing.T) {
@@ -51,7 +65,7 @@ func TestHistogram(t *testing.T) {
 	p.Observe(10)
 	p.Observe(30)
 	mdto := &dto.Metric{}
-	p.Write(mdto)
+	_ = p.Write(mdto)
 	pbuf := bytes.NewBuffer(nil)
 	enc := expfmt.NewEncoder(pbuf, expfmt.NewFormat(expfmt.TypeTextPlain))
 	mf := &dto.MetricFamily{Name: &name, Type: dto.MetricType_HISTOGRAM.Enum(), Metric: []*dto.Metric{mdto}}

summary.go

@@ -8,17 +8,19 @@ import (
 )
 
 type prometheusSummary struct {
-	name string
-	c    *dto.Metric
+	name        string
+	c           *dto.Metric
+	sampleCount uint64
+	SampleSum   float64
 }
 
-func (c prometheusSummary) Update(n float64) {
-	atomic.AddUint64(c.c.Summary.SampleCount, 1)
-	addFloat64(c.c.Summary.SampleSum, n)
+func (c *prometheusSummary) Update(n float64) {
+	atomic.AddUint64(&(c.sampleCount), 1)
+	addFloat64(&(c.SampleSum), n)
 }
 
-func (c prometheusSummary) UpdateDuration(n time.Time) {
-	x := time.Since(n).Seconds()
-	atomic.AddUint64(c.c.Summary.SampleCount, 1)
-	addFloat64(c.c.Summary.SampleSum, x)
+func (c *prometheusSummary) UpdateDuration(t time.Time) {
+	n := time.Since(t).Seconds()
+	atomic.AddUint64(&(c.sampleCount), 1)
+	addFloat64(&(c.SampleSum), n)
 }