Fix lint issues and enable lint in GHA (#45)

* Update all the deprecated references to ioutil so that lint passes

.github/workflows/test-go.yaml

@@ -16,3 +16,13 @@ jobs:
           go-version: '1.19.2' # The Go version to download (if necessary) and use.
       - run: go test ./...
       - run: go build ./cmd/...
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v3
+        with:
+          # Optional: version of golangci-lint to use in form of v1.2 or v1.2.3 or `latest` to use the latest version
+          # https://github.com/golangci/golangci-lint/releases
+          version: v1.50
+          # These options work around the errors in this issue
+          # https://github.com/golangci/golangci-lint-action/issues/244
+          skip-pkg-cache: true
+          skip-build-cache: true

pkg/gitops/syncer.go

@@ -3,7 +3,6 @@ package gitops
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path"
@@ -99,7 +98,7 @@ func NewSyncer(m *v1alpha1.ManifestSync, manager *github.TransportManager, opts
 	}
 	s.log.Info("Creating NewSyncer", "manifest", m)
 	if s.workDir == "" {
-		newDir, err := ioutil.TempDir("", "manifestSync")
+		newDir, err := os.MkdirTemp("", "manifestSync")
 		if err != nil {
 			return nil, errors.Wrapf(err, "Failed to create a temporary working directorry")
 		}
@@ -1192,7 +1191,7 @@ func (s *Syncer) buildImages(sourcePath string, sourceCommit string) error {
 
 		if missingImages {
 			// Since the skaffold config could have been modified to change the registry we need to write it back out
-			f, err := ioutil.TempFile("", "skaffold.*.yaml")
+			f, err := os.CreateTemp("", "skaffold.*.yaml")
 
 			newFile := f.Name()
 
@@ -1324,7 +1323,7 @@ func findKustomizationFiles(root string, repoRoot string, excludes []string, log
 
 // readKustomization will read a kustomization.yaml and return the kustomize object
 func readKustomization(kfDefFile string) (*kustomize.Kustomization, error) {
-	data, err := ioutil.ReadFile(kfDefFile)
+	data, err := os.ReadFile(kfDefFile)
 	if err != nil {
 		return nil, err
 	}

pkg/gitutil/gitutil_test.go

@@ -1,7 +1,6 @@
 package gitutil
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -41,7 +40,7 @@ func Test_LocateRoot(t *testing.T) {
 
 	for _, c := range cases {
 		t.Run(c.name, func(t *testing.T) {
-			outDir, err := ioutil.TempDir("", "LocateRoot")
+			outDir, err := os.MkdirTemp("", "LocateRoot")
 			if err != nil {
 				t.Errorf("Failed to create temporary directory; %v", err)
 				return

pkg/kustomize/dispatcher_test.go

@@ -1,7 +1,6 @@
 package kustomize
 
 import (
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -38,7 +37,7 @@ func Test_runOnDir(t *testing.T) {
 	sourceDir := path.Join(testDir, "source")
 
 	// Create a temporary directory because the function will modify the directory.
-	outDir, err := ioutil.TempDir("", "runOnDir")
+	outDir, err := os.MkdirTemp("", "runOnDir")
 	if err != nil {
 		t.Errorf("Failed to create temporary directory; %v", err)
 		return
@@ -71,7 +70,7 @@ func Test_runOnDir(t *testing.T) {
 
 	for _, n := range names {
 		p := path.Join(outDir, n)
-		actualB, err := ioutil.ReadFile(p)
+		actualB, err := os.ReadFile(p)
 		if err != nil {
 			t.Errorf("Failed to read file: %v; error %v", p, err)
 			continue
@@ -82,7 +81,7 @@ func Test_runOnDir(t *testing.T) {
 		}
 
 		ePath := path.Join(testDir, "expected", n)
-		expectedB, err := ioutil.ReadFile(ePath)
+		expectedB, err := os.ReadFile(ePath)
 		if err != nil {
 			t.Errorf("Failed to read file: %v; error %v", ePath, err)
 			continue

pkg/s3assets/io.go

@@ -4,7 +4,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -17,7 +16,7 @@ import (
 
 // Load reads s3 assets from an S3AssetsList yaml file.
 func Load(assetsFile string) ([]string, error) {
-	data, err := ioutil.ReadFile(assetsFile)
+	data, err := os.ReadFile(assetsFile)
 	if err != nil {
 		return nil, err
 	}
@@ -397,7 +396,7 @@ func (m *uploadManager) Run(asset string) (err error) {
 	}
 	fmt.Printf("Uploading %s\n", asset)
 	sPath := s3.Path{Bucket: m.Bucket, Key: asset}
-	bytes, err := ioutil.ReadFile(filepath.Join(m.absAssetDir, asset))
+	bytes, err := os.ReadFile(filepath.Join(m.absAssetDir, asset))
 	if err != nil {
 		m.err = err
 		return

pkg/s3assets/io_test.go

@@ -1,7 +1,6 @@
 package s3assets
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -55,7 +54,7 @@ func (s *S3IOTestSuite) TestMakeLocalWriter() {
 		},
 	}
 	for name, tc := range testCases {
-		dir, err := ioutil.TempDir(".", "localWriterTest")
+		dir, err := os.MkdirTemp(".", "localWriterTest")
 		s.Assert().NoError(err, "Error making tmp dir", name)
 
 		tc.setup(dir, tc.testPath)

pkg/skaffold/build_output.go

@@ -5,7 +5,7 @@ package skaffold
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"os"
 )
 
@@ -44,12 +44,12 @@ func (t *BuildOutputFileFlag) Set(value string) error {
 	)
 
 	if value == "-" {
-		buf, err = ioutil.ReadAll(os.Stdin)
+		buf, err = io.ReadAll(os.Stdin)
 	} else {
 		if _, err := os.Stat(value); os.IsNotExist(err) {
 			return err
 		}
-		buf, err = ioutil.ReadFile(value)
+		buf, err = os.ReadFile(value)
 	}
 	if err != nil {
 		return err

pkg/skaffold/skaffold.go

@@ -2,7 +2,6 @@ package skaffold
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path"
@@ -151,7 +150,7 @@ func RunBuild(skaffoldFile string, buildDir string, tags []string, sess *session
 		Log: log,
 	}
 
-	dir, err := ioutil.TempDir("", "hydrosSkaffoldBuild")
+	dir, err := os.MkdirTemp("", "hydrosSkaffoldBuild")
 	if err != nil {
 		return errors.Wrapf(err, "Failed to create temporary directory for skaffold")
 	}
@@ -182,7 +181,7 @@ func RunBuild(skaffoldFile string, buildDir string, tags []string, sess *session
 	}
 
 	// TODO(jeremy): Really need to accumulate errors and check no errors occurred.
-	data, err := ioutil.ReadFile(outFile)
+	data, err := os.ReadFile(outFile)
 	if err != nil {
 		return errors.Wrapf(err, "Could not open skaffold output file; %v", outFile)
 	}

tests/configs_test.go

@@ -1,7 +1,6 @@
 package tests
 
 import (
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path"
@@ -51,7 +50,7 @@ func Test_kustomizations(t *testing.T) {
 			t.Errorf("Files should be listed in sorted order in the configMapGenerator in %v;\nGot: %v,\nWant: %v\nDiff: %v", kustomizeFile, actual, want, d)
 		}
 
-		files, err := ioutil.ReadDir(d)
+		files, err := os.ReadDir(d)
 		if err != nil {
 			t.Errorf("Failed to readDir: %v", d)
 			continue
@@ -116,7 +115,7 @@ func Test_build(t *testing.T) {
 // Test_ValidManifestSync validates the manifestsyncs
 func Test_ValidManifestSync(t *testing.T) {
 	for _, d := range testDirs {
-		files, err := ioutil.ReadDir(d)
+		files, err := os.ReadDir(d)
 		if err != nil {
 			if os.IsNotExist(err) {
 				t.Logf("Directory %v doesn't exist; test skipped", d)