[improvement] bump golangci-lint, address linting comments and remove endpoint pkg (#227)

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- [ ] squashed commits
- [ ] includes documentation
- [ ] adds unit tests
- [ ] adds or updates e2e tests

Author: eljohnson92

.golangci.yml

@@ -1,60 +1,185 @@
+version: "2"
 run:
-  timeout: 5m
-  tests: true
-  build-tags:
-    - integration
-
-issues:
-  max-issues-per-linter: 0
-  max-same-issues: 0
-  uniq-by-line: false
-
+  issues-exit-code: 1
 output:
-  sort-results: true
-
+  formats:
+    text:
+      path: stdout
 linters:
   enable:
+    - asasalint
+    - asciicheck
+    - bidichk
+    - bodyclose
     - containedctx
     - contextcheck
+    - copyloopvar
+    - cyclop
+    - decorder
+    - depguard
     - dogsled
-    - errcheck
+    - dupword
+    - durationcheck
+    - errchkjson
+    - errname
     - errorlint
-    - gci
-    - gosec
+    - exhaustive
+    - forbidigo
+    - forcetypeassert
     - gocheckcompilerdirectives
+    - gochecksumtype
     - gocognit
     - goconst
-    - gocritic
-    - gocyclo
-    - godot
-    - gofumpt
-    - gosimple
-    - govet
-    - ineffassign
+    # TODO: enable in gocritic in it's own PR
+#    - gocritic
+    - goprintffuncname
+    - gosec
+    - gosmopolitan
+    - loggercheck
+    - maintidx
+    - makezero
     - misspell
     - mnd
+    - musttag
+    - nestif
     - nilerr
+    - nilnesserr
     - nilnil
+    - noctx
+    - nolintlint
     - paralleltest
+    - prealloc
+    - predeclared
     - protogetter
-    - revive
-    - sloglint
-    - staticcheck
+    - reassign
+    - recvcheck
+    - rowserrcheck
+    - spancheck
+    - sqlclosecheck
+    - testifylint
+    - thelper
+    - unconvert
+    - unparam
+    - usestdlibvars
+    - usetesting
+    - varnamelen
+    - whitespace
+    - zerologlint
+    - govet
+    - ineffassign
     - unused
-    - wsl
-
-linters-settings:
-  paralleltest:
-    ignore-missing: false
-
-  sloglint:
-    kv-only: true
-    key-naming-case: snake
-
-  gci:
-    sections:
-      - standard
-      - default
-      - blank
-      - dot
-      - prefix(github.com/linode)
+  settings:
+    exhaustive:
+      default-signifies-exhaustive: true
+    cyclop:
+      max-complexity: 15
+    depguard:
+      rules:
+        main:
+          files:
+            - $all
+            - '!$test'
+          deny:
+            - pkg: reflect
+              desc: Reflection is never clear.
+            - pkg: gob
+              desc: Please convert types manually
+    dupl:
+      threshold: 100
+    errcheck:
+      check-type-assertions: true
+      check-blank: true
+    goconst:
+      min-len: 3
+      min-occurrences: 5
+    gocritic:
+      enabled-tags:
+        - diagnostic
+        - experimental
+        - opinionated
+        - performance
+        - style
+      settings:
+        captLocal:
+          paramsOnly: true
+        rangeValCopy:
+          sizeThreshold: 32
+    lll:
+      tab-width: 1
+    nolintlint:
+      require-explanation: true
+      require-specific: true
+    prealloc:
+      simple: true
+      range-loops: true
+      for-loops: false
+    unparam:
+      check-exported: false
+    varnamelen:
+      min-name-length: 2
+  exclusions:
+    generated: lax
+    rules:
+      - linters:
+          - copyloopvar
+          - dupl
+          - errcheck
+          - gocyclo
+          - gosec
+          - maintidx
+          - unparam
+          - containedctx
+        path: _test\.go
+      - linters:
+          - dupl
+        path: _conversion\.go
+      - linters:
+          - gocritic
+        path: _test\.go
+        text: (unnamedResult|exitAfterDefer)
+      - linters:
+          - gocritic
+        text: '(hugeParam|rangeValCopy):'
+      - linters:
+          - staticcheck
+        text: 'SA3000:'
+      - linters:
+          - gosec
+        text: 'G101:'
+      - linters:
+          - gosec
+        text: 'G104:'
+    paths:
+      - cmd/main.go
+      - third_party$
+      - builtin$
+      - examples$
+issues:
+  max-issues-per-linter: 0
+  max-same-issues: 0
+  new: false
+formatters:
+  enable:
+    - gci
+    - gofmt
+    - goimports
+  settings:
+    gci:
+      sections:
+        - standard
+        - default
+        - blank
+        - dot
+        - prefix(github.com/linode/linode-cosi-driver)
+    gofmt:
+      simplify: true
+    goimports:
+      local-prefixes:
+        - github.com/linode/linode-cosi-driver
+  exclusions:
+    generated: lax
+    paths:
+      - cmd/main.go
+      - third_party$
+      - builtin$
+      - examples$

Makefile

@@ -221,7 +221,7 @@ TILT           			?= $(LOCALBIN)/tilt
 ## Tool Versions
 CHAINSAW_VERSION                ?= v0.2.12
 CTLPTL_VERSION                  ?= v0.8.39
-GOLANGCI_LINT_VERSION           ?= v1.64.5
+GOLANGCI_LINT_VERSION           ?= v2.7.1
 HELM_VERSION                    ?= v3.17.1
 HELM_DOCS_VERSION               ?= v1.14.2
 HELM_VALUES_SCHEMA_JSON_VERSION ?= v1.7.0
@@ -242,7 +242,7 @@ $(CTLPTL)-$(CTLPTL_VERSION): $(LOCALBIN)
 .PHONY: golangci-lint
 golangci-lint: $(GOLANGCI_LINT)-$(GOLANGCI_LINT_VERSION) ## Download golangci-lint locally if necessary.
 $(GOLANGCI_LINT)-$(GOLANGCI_LINT_VERSION): $(LOCALBIN)
-	$(call go-install-tool,$(GOLANGCI_LINT),github.com/golangci/golangci-lint/cmd/golangci-lint,$(GOLANGCI_LINT_VERSION))
+	$(call go-install-tool,$(GOLANGCI_LINT),github.com/golangci/golangci-lint/v2/cmd/golangci-lint,$(GOLANGCI_LINT_VERSION))
 
 .PHONY: helm
 helm: $(HELM)-$(HELM_VERSION) ## Download helm locally if necessary.

cmd/linode-cosi-driver/main.go

@@ -19,6 +19,7 @@ import (
 	"errors"
 	"fmt"
 	"log/slog"
+	"net"
 	"net/url"
 	"os"
 	"os/signal"
@@ -32,7 +33,6 @@ import (
 	"google.golang.org/grpc"
 	cosi "sigs.k8s.io/container-object-storage-interface-spec"
 
-	"github.com/linode/linode-cosi-driver/pkg/endpoint"
 	"github.com/linode/linode-cosi-driver/pkg/envflag"
 	grpchandlers "github.com/linode/linode-cosi-driver/pkg/grpc"
 	"github.com/linode/linode-cosi-driver/pkg/linodeclient"
@@ -89,6 +89,7 @@ type mainOptions struct {
 	s3SecretKey            string
 }
 
+//nolint:cyclop //TODO: reduce complexity
 func run(ctx context.Context, log *slog.Logger, opts mainOptions) error {
 	_, err := maxprocs.Set(maxprocs.Logger(logutils.ForMaxprocs(log.Handler())))
 	if err != nil {
@@ -171,15 +172,19 @@ func run(ctx context.Context, log *slog.Logger, opts mainOptions) error {
 		return fmt.Errorf("unable to parse COSI endpoint: %w", err)
 	}
 
-	// create the endpoint handler
-	ep := endpoint.New(endpointURL)
-	defer ep.Close()
-
-	lis, err := ep.Listener(ctx)
+	// create the unix socket listener directly
+	if endpointURL.Scheme != "unix" {
+		return fmt.Errorf("only unix scheme is supported for endpoint")
+	}
+	listenConfig := net.ListenConfig{}
+	lis, err := listenConfig.Listen(ctx, "unix", endpointURL.Path)
 	if err != nil {
-		return fmt.Errorf("unable to create new listener: %w", err)
+		return fmt.Errorf("unable to create unix listener: %w", err)
 	}
-	defer lis.Close()
+	defer func() {
+		lis.Close()                 //nolint:errcheck //ignore close error
+		os.Remove(endpointURL.Path) //nolint:errcheck //ignore close error
+	}()
 
 	// create the grpcServer
 	srv, err := grpcServer(ctx, log, idSrv, prvSrv)
@@ -232,7 +237,7 @@ func grpcServer(ctx context.Context,
 // shutdown handles shutdown with grace period consideration.
 func shutdown(ctx context.Context,
 	wg *sync.WaitGroup,
-	g *grpc.Server,
+	server *grpc.Server,
 ) {
 	<-ctx.Done()
 	defer wg.Done()
@@ -243,22 +248,22 @@ func shutdown(ctx context.Context,
 	dctx, stop := context.WithTimeout(context.Background(), gracePeriod)
 	defer stop()
 
-	c := make(chan struct{})
+	channel := make(chan struct{})
 
-	if g != nil {
+	if server != nil {
 		go func() {
-			g.GracefulStop()
-			c <- struct{}{}
+			server.GracefulStop()
+			channel <- struct{}{}
 		}()
 
 		for {
 			select {
 			case <-dctx.Done():
 				slog.Warn("Forcing shutdown")
-				g.Stop()
+				server.Stop()
 
 				return
-			case <-c:
+			case <-channel:
 				return
 			}
 		}

cmd/linode-cosi-driver/main_test.go

@@ -19,15 +19,12 @@ import (
 	"errors"
 	"io"
 	"log/slog"
-	"os"
 	"testing"
 	"time"
-
-	"github.com/linode/linode-cosi-driver/pkg/testutils"
 )
 
 func TestRun(t *testing.T) {
-	t.Parallel()
+	t.Setenv("LINODE_TOKEN", "test")
 
 	for _, tc := range []struct {
 		testName      string // required
@@ -46,8 +43,6 @@ func TestRun(t *testing.T) {
 		t.Run(tc.testName, func(t *testing.T) {
 			t.Parallel()
 
-			os.Setenv("LINODE_TOKEN", "test")
-
 			noopLog := slog.New(slog.NewTextHandler(
 				io.Discard,
 				&slog.HandlerOptions{Level: slog.LevelError},
@@ -67,8 +62,7 @@ func TestRun(t *testing.T) {
 			ctx, cancel := context.WithTimeout(t.Context(), time.Second)
 			defer cancel()
 
-			tmp := testutils.MustMkdirTemp()
-			defer os.RemoveAll(tmp)
+			tmp := t.TempDir()
 
 			defaultOpts.cosiEndpoint = "unix://" + tmp + defaultOpts.cosiEndpoint