fix variable shadowing error and linter config

Author: junedev

.golangci.yml

@@ -11,15 +11,28 @@ linters:
 
 run:
   deadline: 10m
+  modules-download-mode: vendor
 
 issues:
+  exclude-use-default: false
   exclude-rules:
     - path: _test\.go
       linters:
         - dupl
         - goconst
         - gosec
+    - linters:
+        - govet
+      text: 'shadow: declaration of "err" shadows declaration'
+    - linters:
+        - golint
+      text: 'in another file for this package'
 
 linters-settings:
   gocyclo:
     min-complexity: 10
+  golint:
+    min-confidence: 0
+  govet:
+    check-shadowing: true
+

request.go

@@ -13,20 +13,20 @@ import (
 	"github.com/pkg/errors"
 )
 
-// client is the global client instance.
-var client *http.Client
+// cachedClient is the global client instance.
+var cachedClient *http.Client
 
 // defaultTimeout is the timeout applied if there is none provided.
 var defaultTimeout = 30 * time.Second
 
 // getCachedClient returns the client instance or creates it if it did not exist.
 // The client does not follow redirects and has a timeout of defaultTimeout.
 func getCachedClient() *http.Client {
-	if client == nil {
-		client = GetClient()
+	if cachedClient == nil {
+		cachedClient = GetClient()
 	}
 
-	return client
+	return cachedClient
 }
 
 // GetClient returns an http client that does not follow redirects and has a timeout of defaultTimeout.
@@ -58,7 +58,7 @@ func Do(params Params, responseBody interface{}) (returnErr error) {
 		return err
 	}
 
-	client := getClient(params.Timeout)
+	client := selectClient(params.Timeout)
 	res, err := client.Do(req)
 	if err != nil {
 		return errors.Wrap(err, "failed to send request")
@@ -90,7 +90,7 @@ func DoWithStringResponse(params Params) (result string, returnErr error) {
 		return "", err
 	}
 
-	client := getClient(params.Timeout)
+	client := selectClient(params.Timeout)
 	res, err := client.Do(req)
 	if err != nil {
 		return "", errors.Wrap(err, "failed to send request")
@@ -171,9 +171,9 @@ func convertToReader(body interface{}) (io.Reader, error) {
 	return buffer, nil
 }
 
-func getClient(timeout time.Duration) *http.Client {
+func selectClient(timeout time.Duration) *http.Client {
 	if timeout != 0 {
-		client = GetClient()
+		client := GetClient()
 		client.Timeout = timeout
 		return client
 	}

request_test.go

@@ -41,12 +41,12 @@ func TestGetClient(t *testing.T) {
 		stdClient := http.Client{}
 		r, err := stdClient.Get(ts.URL)
 		assert.Error(t, err)
-		r.Body.Close()
+		assert.NoError(t, r.Body.Close())
 
 		client := GetClient()
 		res, err := client.Get(ts.URL)
 		assert.Equal(t, "/////", res.Header.Get("Location"))
-		res.Body.Close()
+		assert.NoError(t, res.Body.Close())
 		assert.NoError(t, err)
 	})
 }