add new linters and fix unnecessary type conversions (#3835)

.golangci.yml

@@ -8,15 +8,20 @@ linters-settings:
 linters:
   disable-all: true
   enable:
-    - revive
     - typecheck
     - goimports
     - misspell
     - govet
+    - revive
     - ineffassign
     - gosimple
     - deadcode
     - structcheck
+    - gomodguard
+    - gofmt
+    - unused
+    - structcheck
+    - varcheck
 
 issues:
   exclude-use-default: false
@@ -24,5 +29,6 @@ issues:
     - instead of using struct literal
     - should have a package comment
     - error strings should not be capitalized or end with punctuation or a newline
+      
 service:
   golangci-lint-version: 1.20.0 # use the fixed version to not introduce new linters unexpectedly

cmd/admin-info.go

@@ -224,7 +224,7 @@ func (u clusterStruct) String() (msg string) {
 
 	// Summary on used space, total no of buckets and
 	// total no of objects at the Cluster level
-	usedTotal := humanize.IBytes(uint64(u.Info.Usage.Size))
+	usedTotal := humanize.IBytes(u.Info.Usage.Size)
 	if u.Info.Buckets.Count > 0 {
 		msg += fmt.Sprintf("%s Used, %s, %s\n", usedTotal,
 			english.Plural(int(u.Info.Buckets.Count), "Bucket", ""),
@@ -281,7 +281,7 @@ func mainAdminInfo(ctx *cli.Context) error {
 		clusterInfo.Error = ""
 	}
 	clusterInfo.Info = admInfo
-	printMsg(clusterStruct(clusterInfo))
+	printMsg(clusterInfo)
 
 	return nil
 }

cmd/admin-policy-add.go

@@ -134,7 +134,7 @@ func mainAdminPolicyAdd(ctx *cli.Context) error {
 	client, err := newAdminClient(aliasedURL)
 	fatalIf(err, "Unable to initialize admin connection.")
 
-	fatalIf(probe.NewError(client.AddCannedPolicy(globalContext, args.Get(1), []byte(policy))).Trace(args...), "Unable to add new policy")
+	fatalIf(probe.NewError(client.AddCannedPolicy(globalContext, args.Get(1), policy)).Trace(args...), "Unable to add new policy")
 
 	printMsg(userPolicyMessage{
 		op:     "add",

cmd/admin-speedtest.go

@@ -86,10 +86,10 @@ func (s speedTestResult) String() (msg string) {
 	if globalSpeedTestVerbose {
 		msg += "\n"
 	}
-	msg += fmt.Sprintf("PUT: %s/s, %d objs/s\n", humanize.IBytes(uint64(s.PUTStats.ThroughputPerSec)), s.PUTStats.ObjectsPerSec)
+	msg += fmt.Sprintf("PUT: %s/s, %d objs/s\n", humanize.IBytes(s.PUTStats.ThroughputPerSec), s.PUTStats.ObjectsPerSec)
 	if globalSpeedTestVerbose {
 		for _, node := range s.PUTStats.Servers {
-			msg += fmt.Sprintf("   * %s:, %s/s, %d objs/s", node.Endpoint, humanize.IBytes(uint64(node.ThroughputPerSec)), node.ObjectsPerSec)
+			msg += fmt.Sprintf("   * %s:, %s/s, %d objs/s", node.Endpoint, humanize.IBytes(node.ThroughputPerSec), node.ObjectsPerSec)
 			if node.Err != "" {
 				msg += " error: " + node.Err
 			}
@@ -100,10 +100,10 @@ func (s speedTestResult) String() (msg string) {
 	if globalSpeedTestVerbose {
 		msg += "\n"
 	}
-	msg += fmt.Sprintf("GET: %s/s, %d objs/s\n", humanize.IBytes(uint64(s.GETStats.ThroughputPerSec)), s.GETStats.ObjectsPerSec)
+	msg += fmt.Sprintf("GET: %s/s, %d objs/s\n", humanize.IBytes(s.GETStats.ThroughputPerSec), s.GETStats.ObjectsPerSec)
 	if globalSpeedTestVerbose {
 		for _, node := range s.GETStats.Servers {
-			msg += fmt.Sprintf("   * %s:, %s/s, %d objs/s", node.Endpoint, humanize.IBytes(uint64(node.ThroughputPerSec)), node.ObjectsPerSec)
+			msg += fmt.Sprintf("   * %s:, %s/s, %d objs/s", node.Endpoint, humanize.IBytes(node.ThroughputPerSec), node.ObjectsPerSec)
 			if node.Err != "" {
 				msg += " error: " + node.Err
 			}

cmd/admin-subnet-health.go

@@ -321,7 +321,7 @@ func uploadHealthReport(alias string, filename string, reqURL string, headers ma
 	}
 
 	msg := "MinIO Health data was successfully uploaded to SUBNET."
-	clusterURL, _ := url.PathUnescape(gjson.Get(string(resp), "cluster_url").String())
+	clusterURL, _ := url.PathUnescape(gjson.Get(resp, "cluster_url").String())
 	if len(clusterURL) > 0 {
 		msg += fmt.Sprintf(" Can be viewed at: %s", clusterURL)
 	}

cmd/admin-trace.go

@@ -478,7 +478,7 @@ func colorizedNodeName(nodeName string) string {
 	nodeHash := fnv.New32a()
 	nodeHash.Write([]byte(nodeName))
 	nHashSum := nodeHash.Sum32()
-	idx := uint32(nHashSum) % uint32(len(colors))
+	idx := nHashSum % uint32(len(colors))
 	return console.Colorize(fmt.Sprintf("Node%d", colors[idx]), nodeName)
 }
 

cmd/anonymous-main.go

@@ -164,7 +164,7 @@ type anonymousLinksMessage struct {
 
 // String colorized access message.
 func (s anonymousLinksMessage) String() string {
-	return console.Colorize("Anonymous", string(s.URL))
+	return console.Colorize("Anonymous", s.URL)
 }
 
 // JSON jsonified anonymous message.
@@ -203,7 +203,7 @@ func checkAnonymousSyntax(ctx *cli.Context) {
 			accessPerms(secondArg) != accessPrivate &&
 			accessPerms(secondArg) != accessPublic {
 			fatalIf(errDummy().Trace(),
-				"Unrecognized permission `"+string(secondArg)+"`. Allowed values are [private, public, download, upload].")
+				"Unrecognized permission `"+secondArg+"`. Allowed values are [private, public, download, upload].")
 		}
 
 	case "set-json":

cmd/client-fs.go

@@ -86,7 +86,7 @@ func isNotSupported(e error) bool {
 	}
 
 	// check if filesystem supports extended attributes
-	return errno.Err == syscall.Errno(syscall.ENOTSUP) || errno.Err == syscall.Errno(syscall.EOPNOTSUPP)
+	return errno.Err == syscall.ENOTSUP || errno.Err == syscall.EOPNOTSUPP
 }
 
 // isIgnoredFile returns true if 'filename' is on the exclude list.

cmd/client-s3.go

@@ -1900,26 +1900,6 @@ func (c *S3Client) listIncompleteRecursiveInRoutine(ctx context.Context, content
 	}
 }
 
-// Convert objectMultipartInfo to ClientContent
-func (c *S3Client) objectMultipartInfo2ClientContent(bucket string, entry minio.ObjectMultipartInfo) ClientContent {
-
-	content := ClientContent{}
-	url := c.targetURL.Clone()
-	// Join bucket and incoming object key.
-	url.Path = c.joinPath(bucket, entry.Key)
-	content.URL = url
-	content.Size = entry.Size
-	content.Time = entry.Initiated
-
-	if strings.HasSuffix(entry.Key, string(c.targetURL.Separator)) {
-		content.Type = os.ModeDir
-	} else {
-		content.Type = os.ModeTemporary
-	}
-
-	return content
-}
-
 // Returns new path by joining path segments with URL path separator.
 func (c *S3Client) joinPath(bucket string, objects ...string) string {
 	p := string(c.targetURL.Separator) + bucket

cmd/client-s3_test.go

@@ -158,9 +158,9 @@ func (h objectHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 // Test bucket operations.
 func (s *TestSuite) TestBucketOperations(c *C) {
-	bucket := bucketHandler(bucketHandler{
+	bucket := bucketHandler{
 		resource: "/bucket/",
-	})
+	}
 	server := httptest.NewServer(bucket)
 	defer server.Close()
 
@@ -205,10 +205,10 @@ func (s *TestSuite) TestBucketOperations(c *C) {
 
 // Test all object operations.
 func (s *TestSuite) TestObjectOperations(c *C) {
-	object := objectHandler(objectHandler{
+	object := objectHandler{
 		resource: "/bucket/object",
 		data:     []byte("Hello, World"),
-	})
+	}
 	server := httptest.NewServer(object)
 	defer server.Close()
 

cmd/common-methods.go

@@ -576,7 +576,7 @@ func uploadSourceToTargetURL(ctx context.Context, urls URLs, progress io.Reader,
 			md5:              urls.MD5,
 			disableMultipart: urls.DisableMultipart,
 			isPreserve:       preserve,
-			multipartSize:    uint64(multipartSize),
+			multipartSize:    multipartSize,
 			multipartThreads: uint(multipartThreads),
 		}
 

cmd/policy-main.go

@@ -162,7 +162,7 @@ type policyLinksMessage struct {
 
 // String colorized access message.
 func (s policyLinksMessage) String() string {
-	return console.Colorize("Policy", string(s.URL))
+	return console.Colorize("Policy", s.URL)
 }
 
 // JSON jsonified policy message.
@@ -200,7 +200,7 @@ func checkPolicySyntax(ctx *cli.Context) {
 			accessPerms(secondArg) != accessUpload &&
 			accessPerms(secondArg) != accessPublic {
 			fatalIf(errDummy().Trace(),
-				"Unrecognized permission `"+string(secondArg)+"`. Allowed values are [none, download, upload, public].")
+				"Unrecognized permission `"+secondArg+"`. Allowed values are [none, download, upload, public].")
 		}
 
 	case "set-json":

cmd/utils.go

@@ -343,7 +343,7 @@ func parseAtimeMtime(attr map[string]string) (atime, mtime time.Time, err *probe
 				return atime, mtime, probe.NewError(e)
 			}
 		}
-		atime = time.Unix(int64(atim), int64(atimnsec))
+		atime = time.Unix(atim, atimnsec)
 	}
 
 	if val, ok := attr["mtime"]; ok {
@@ -359,7 +359,7 @@ func parseAtimeMtime(attr map[string]string) (atime, mtime time.Time, err *probe
 				return atime, mtime, probe.NewError(e)
 			}
 		}
-		mtime = time.Unix(int64(mtim), int64(mtimnsec))
+		mtime = time.Unix(mtim, mtimnsec)
 	}
 	return atime, mtime, nil
 }