fix golangci-lint reported errors, update configuration

.golangci.yml

@@ -1,12 +1,9 @@
 linters-settings:
   govet:
-    check-shadowing: true
-  golint:
-    min-confidence: 0
+    enable:
+      - shadow
   gocyclo:
     min-complexity: 15
-  maligned:
-    suggest-new: true
   dupl:
     threshold: 100
   goconst:
@@ -26,44 +23,34 @@ linters-settings:
 
 linters:
   enable:
-    - megacheck
+    - staticcheck
+    - gosimple
     - revive
     - govet
     - unconvert
-    - megacheck
-    - gas
+    - unused
+    - gosec
     - gocyclo
     - dupl
     - misspell
     - unparam
-    - unused
     - typecheck
     - ineffassign
     - stylecheck
     - gochecknoinits
     - exportloopref
     - gocritic
     - nakedret
-    - gosimple
     - prealloc
   fast: false
   disable-all: true
 
-run:
-  output:
-    format: tab
-  skip-dirs:
-    - vendor
-
 issues:
   exclude-rules:
     - text: 'Deferring unsafe method "Close" on type "io.ReadCloser"'
       linters:
         - gosec
-    - text: "should have a package comment, unless it's in another file for this package"
-      linters:
-        - golint
     - path: _test\.go
       linters:
         - dupl
-  exclude-use-default: false
+  exclude-use-default: false

benchmarks.go

@@ -55,10 +55,10 @@ func NewBenchmarks() *Benchmarks {
 // Default is 15 minutes. The increase of this range will change memory utilization as each second of the range
 // kept as benchData aggregate. The default means 15*60 = 900 seconds of data aggregate.
 // Larger range allows for longer time periods to be benchmarked.
-func (b *Benchmarks) WithTimeRange(max time.Duration) *Benchmarks {
+func (b *Benchmarks) WithTimeRange(maximum time.Duration) *Benchmarks {
 	b.lock.Lock()
 	defer b.lock.Unlock()
-	b.maxTimeRange = max
+	b.maxTimeRange = maximum
 	return b
 }
 

logger/options.go

@@ -13,10 +13,10 @@ func WithBody(l *Middleware) {
 }
 
 // MaxBodySize sets size of the logged part of the request body.
-func MaxBodySize(max int) Option {
+func MaxBodySize(maximum int) Option {
 	return func(l *Middleware) {
-		if max >= 0 {
-			l.maxBodySize = max
+		if maximum >= 0 {
+			l.maxBodySize = maximum
 		}
 	}
 }