Update golangci-lint config for v2 (#1034)

This brings the common files in line with other prometheus repos. Most of these settings are coppied from prometheus/prometheus. Where it was a small change, I have enabled the new linte
rs and made the fixes. The remaining linters that are commented out deserve to be enabled and the fixes applied as independent changes.

Signed-off-by: Joe Adams <[email protected]>

Author: sysadmind

.github/workflows/golangci-lint.yml

@@ -33,7 +33,7 @@ jobs:
         run: sudo apt-get update && sudo apt-get -y install libsnmp-dev
         if: github.repository == 'prometheus/snmp_exporter'
       - name: Lint
-        uses: golangci/golangci-lint-action@4696ba8babb6127d732c3c6dde519db15edab9ea # v6.5.1
+        uses: golangci/golangci-lint-action@1481404843c368bc19ca9406f87d6e0fc97bdcfd # v7.0.0
         with:
           args: --verbose
-          version: v1.64.6
+          version: v2.0.2

.golangci.yml

@@ -1,19 +1,124 @@
 ---
+version: "2"
+
+formatters:
+  enable:
+    - gci
+    - gofumpt
+  settings:
+    gci:
+      sections:
+        - standard
+        - prefix(github.com/prometheus-community/elasticsearch_exporter)
+        - default
+
 linters:
   enable:
+    - depguard
+    # TODO(@sysadmind): Enable and fix the issues.
+    # - errorlint
+    - exptostd
+    # TODO(@sysadmind): Enable and fix the issues.
+    # - gocritic
+    # - godot
+    - loggercheck
+    # TODO(@sysadmind): Enable and fix the issues.
+    # - misspell
+    - nilnesserr
+    - nolintlint
+    # TODO(@sysadmind): Enable and fix the issues.
+    # - perfsprint
+    - predeclared
     - revive
     - sloglint
+    - testifylint
+    - unconvert
+    - unused
+    - usestdlibvars
+    - whitespace
+  exclusions:
+    rules:
+      # Disable errcheck for test files.
+      - linters:
+          - errcheck
+        path: _test.go
 
-issues:
-  exclude-rules:
-    - path: _test.go
-      linters:
-        - errcheck
+      # Disable errcheck rule for some specific functions.
+      - linters:
+          - errcheck
+        # Taken from the default exclusions in v1.
+        text: Error return value of .((os\.)?std(out|err)\..*|.*Close|.*Flush|os\.Remove(All)?|.*print(f|ln)?|os\.(Un)?Setenv). is not checked
 
-linters-settings:
-  revive:
-    rules:
-      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#unused-parameter
-      - name: unused-parameter
-        severity: warning
-        disabled: true
+  settings:
+    revive:
+      rules:
+        # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md
+        - name: blank-imports
+        - name: comment-spacings
+        - name: context-as-argument
+          arguments:
+            # Allow functions with test or bench signatures.
+            - allowTypesBefore: '*testing.T,testing.TB'
+        - name: context-keys-type
+        - name: dot-imports
+        - name: early-return
+          arguments:
+            - "preserveScope"
+        # A lot of false positives: incorrectly identifies channel draining as "empty code block".
+        # See https://github.com/mgechev/revive/issues/386
+        - name: empty-block
+          disabled: true
+        - name: error-naming
+        - name: error-return
+        - name: error-strings
+        - name: errorf
+        # TODO(@sysadmind): Enable and fix the issues.
+        # - name: exported
+        - name: increment-decrement
+        - name: indent-error-flow
+          arguments:
+            - "preserveScope"
+        - name: package-comments
+          # TODO(beorn7/sysadmind): Currently, we have a lot of missing package doc comments. Maybe we should have them.
+          disabled: true
+        - name: range
+        - name: receiver-naming
+        - name: redefines-builtin-id
+        - name: superfluous-else
+          arguments:
+            - "preserveScope"
+        - name: time-naming
+        # TODO(@sysadmind): Enable and fix the issues.
+        # - name: unexported-return
+        - name: unreachable-code
+        - name: unused-parameter
+          severity: warning
+          disabled: true
+        - name: var-declaration
+        - name: var-naming
+
+    depguard:
+      rules:
+        main:
+          deny:
+            - pkg: "sync/atomic"
+              desc: "Use go.uber.org/atomic instead of sync/atomic"
+            - pkg: "github.com/stretchr/testify/assert"
+              desc: "Use github.com/stretchr/testify/require instead of github.com/stretchr/testify/assert"
+            - pkg: "github.com/go-kit/kit/log"
+              desc: "Use github.com/go-kit/log instead of github.com/go-kit/kit/log"
+            - pkg: "io/ioutil"
+              desc: "Use corresponding 'os' or 'io' functions instead."
+            - pkg: "regexp"
+              desc: "Use github.com/grafana/regexp instead of regexp"
+            - pkg: "github.com/pkg/errors"
+              desc: "Use 'errors' or 'fmt' instead of github.com/pkg/errors"
+            - pkg: "gzip"
+              desc: "Use github.com/klauspost/compress instead of gzip"
+            - pkg: "zlib"
+              desc: "Use github.com/klauspost/compress instead of zlib"
+            - pkg: "golang.org/x/exp/slices"
+              desc: "Use 'slices' instead."
+issues:
+  max-issues-per-linter: 0
+  max-same-issues: 0

Makefile.common

@@ -61,7 +61,7 @@ PROMU_URL     := https://github.com/prometheus/promu/releases/download/v$(PROMU_
 SKIP_GOLANGCI_LINT :=
 GOLANGCI_LINT :=
 GOLANGCI_LINT_OPTS ?=
-GOLANGCI_LINT_VERSION ?= v1.64.6
+GOLANGCI_LINT_VERSION ?= v2.0.2
 # golangci-lint only supports linux, darwin and windows platforms on i386/amd64/arm64.
 # windows isn't included here because of the path separator being different.
 ifeq ($(GOHOSTOS),$(filter $(GOHOSTOS),linux darwin))

collector/cluster_settings.go

@@ -151,7 +151,7 @@ func (c *ClusterSettingsCollector) Update(ctx context.Context, ch chan<- prometh
 	q.Set("include_defaults", "true")
 	u.RawQuery = q.Encode()
 
-	req, err := http.NewRequestWithContext(ctx, "GET", u.String(), nil)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), nil)
 	if err != nil {
 		return err
 	}

collector/data_stream.go

@@ -113,9 +113,7 @@ func (ds *DataStream) Update(ctx context.Context, ch chan<- prometheus.Metric) e
 			float64(dataStream.StoreSizeBytes),
 			dataStream.DataStream,
 		)
-
 	}
 
 	return nil
-
 }

collector/data_stream_test.go

@@ -27,7 +27,6 @@ import (
 )
 
 func TestDataStream(t *testing.T) {
-
 	tests := []struct {
 		name string
 		file string

collector/ilm.go

@@ -122,7 +122,6 @@ func (i *ILM) Update(ctx context.Context, ch chan<- prometheus.Metric) error {
 			bool2Float(statusActive),
 			status,
 		)
-
 	}
 
 	return nil

collector/ilm_test.go

@@ -54,14 +54,12 @@ func TestILM(t *testing.T) {
 			indexF, err := os.Open(path.Join("../fixtures/ilm_indices", tt.file))
 			if err != nil {
 				t.Fatal(err)
-
 			}
 			defer indexF.Close()
 
 			statusF, err := os.Open(path.Join("../fixtures/ilm_status", tt.file))
 			if err != nil {
 				t.Fatal(err)
-
 			}
 			defer statusF.Close()
 
@@ -75,7 +73,6 @@ func TestILM(t *testing.T) {
 				})
 
 				sm.ServeHTTP(w, r)
-
 			}))
 			defer ts.Close()
 

collector/indices.go

@@ -22,8 +22,9 @@ import (
 	"sort"
 	"strconv"
 
-	"github.com/prometheus-community/elasticsearch_exporter/pkg/clusterinfo"
 	"github.com/prometheus/client_golang/prometheus"
+
+	"github.com/prometheus-community/elasticsearch_exporter/pkg/clusterinfo"
 )
 
 var (
@@ -448,7 +449,6 @@ type Indices struct {
 
 // NewIndices defines Indices Prometheus metrics
 func NewIndices(logger *slog.Logger, client *http.Client, url *url.URL, shards bool, includeAliases bool) *Indices {
-
 	indices := &Indices{
 		logger:        logger,
 		client:        client,
@@ -661,7 +661,6 @@ func (i *Indices) Collect(ch chan<- prometheus.Metric) {
 
 	// Index stats
 	for indexName, indexStats := range indexStatsResp.Indices {
-
 		ch <- prometheus.MustNewConstMetric(
 			indicesDocsPrimary,
 			prometheus.GaugeValue,

collector/indices_mappings.go

@@ -25,9 +25,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 )
 
-var (
-	defaultIndicesMappingsLabels = []string{"index"}
-)
+var defaultIndicesMappingsLabels = []string{"index"}
 
 type indicesMappingsMetric struct {
 	Type  prometheus.ValueType
@@ -72,7 +70,6 @@ func NewIndicesMappings(logger *slog.Logger, client *http.Client, url *url.URL)
 func countFieldsRecursive(properties IndexMappingProperties, fieldCounter float64) float64 {
 	// iterate over all properties
 	for _, property := range properties {
-
 		if property.Type != nil && *property.Type != "object" {
 			// property has a type set - counts as a field unless the value is object
 			// as the recursion below will handle counting that

collector/indices_settings.go

@@ -39,8 +39,8 @@ type IndicesSettings struct {
 
 var (
 	defaultIndicesTotalFieldsLabels = []string{"index"}
-	defaultTotalFieldsValue         = 1000 //es default configuration for total fields
-	defaultDateCreation             = 0    //es index default creation date
+	defaultTotalFieldsValue         = 1000 // es default configuration for total fields
+	defaultDateCreation             = 0    // es index default creation date
 )
 
 type indicesSettingsMetric struct {
@@ -153,7 +153,6 @@ func (cs *IndicesSettings) getAndParseURL(u *url.URL, data interface{}) error {
 }
 
 func (cs *IndicesSettings) fetchAndDecodeIndicesSettings() (IndicesSettingsResponse, error) {
-
 	u := *cs.url
 	u.Path = path.Join(u.Path, "/_all/_settings")
 	var asr IndicesSettingsResponse

collector/indices_test.go

@@ -2153,7 +2153,6 @@ func TestIndices(t *testing.T) {
 				default:
 					http.Error(w, "Not Found", http.StatusNotFound)
 				}
-
 			}))
 			defer ts.Close()
 

collector/nodes.go

@@ -69,12 +69,10 @@ func getRoles(node NodeStatsNodeResponse) map[string]bool {
 	return roles
 }
 
-var (
-	nodesRolesMetric = prometheus.NewDesc(
-		prometheus.BuildFQName(namespace, "nodes", "roles"),
-		"Node roles",
-		append(defaultRoleLabels, "role"), nil,
-	)
+var nodesRolesMetric = prometheus.NewDesc(
+	prometheus.BuildFQName(namespace, "nodes", "roles"),
+	"Node roles",
+	append(defaultRoleLabels, "role"), nil,
 )
 
 var (
@@ -2012,6 +2010,5 @@ func (c *Nodes) Collect(ch chan<- prometheus.Metric) {
 				)
 			}
 		}
-
 	}
 }

collector/shards.go

@@ -21,9 +21,9 @@ import (
 	"net/url"
 	"path"
 
-	"github.com/prometheus-community/elasticsearch_exporter/pkg/clusterinfo"
-
 	"github.com/prometheus/client_golang/prometheus"
+
+	"github.com/prometheus-community/elasticsearch_exporter/pkg/clusterinfo"
 )
 
 // ShardResponse has shard's node and index info
@@ -66,7 +66,6 @@ type nodeShardMetric struct {
 
 // NewShards defines Shards Prometheus metrics
 func NewShards(logger *slog.Logger, client *http.Client, url *url.URL) *Shards {
-
 	nodeLabels := labels{
 		keys: func(...string) []string {
 			return []string{"node", "cluster"}
@@ -103,7 +102,8 @@ func NewShards(logger *slog.Logger, client *http.Client, url *url.URL) *Shards {
 					return shards
 				},
 				Labels: nodeLabels,
-			}},
+			},
+		},
 
 		jsonParseFailures: prometheus.NewCounter(prometheus.CounterOpts{
 			Name: prometheus.BuildFQName(namespace, "node_shards", "json_parse_failures"),
@@ -164,7 +164,6 @@ func (s *Shards) getAndParseURL(u *url.URL) ([]ShardResponse, error) {
 }
 
 func (s *Shards) fetchAndDecodeShards() ([]ShardResponse, error) {
-
 	u := *s.url
 	u.Path = path.Join(u.Path, "/_cat/shards")
 	q := u.Query()
@@ -179,7 +178,6 @@ func (s *Shards) fetchAndDecodeShards() ([]ShardResponse, error) {
 
 // Collect number of shards on each node
 func (s *Shards) Collect(ch chan<- prometheus.Metric) {
-
 	defer func() {
 		ch <- s.jsonParseFailures
 	}()

collector/shards_test.go

@@ -79,6 +79,5 @@ func TestShards(t *testing.T) {
 				t.Fatal(err)
 			}
 		})
-
 	}
 }

collector/slm.go

@@ -23,9 +23,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 )
 
-var (
-	statuses = []string{"RUNNING", "STOPPING", "STOPPED"}
-)
+var statuses = []string{"RUNNING", "STOPPING", "STOPPED"}
 
 var (
 	slmRetentionRunsTotal = prometheus.NewDesc(
@@ -173,7 +171,7 @@ func (s *SLM) Update(ctx context.Context, ch chan<- prometheus.Metric) error {
 	}
 
 	for _, status := range statuses {
-		var value float64 = 0
+		var value float64
 		if slmStatusResp.OperationMode == status {
 			value = 1
 		}
@@ -253,9 +251,7 @@ func (s *SLM) Update(ctx context.Context, ch chan<- prometheus.Metric) error {
 			float64(policy.SnapshotDeletionFailures),
 			policy.Policy,
 		)
-
 	}
 
 	return nil
-
 }