Use constant for GET/PUT/POST methods

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

commands/fetch_templates.go

@@ -78,7 +78,7 @@ func fetchMasterZip(templateUrl string) error {
 		timeout := 120 * time.Second
 		client := proxy.MakeHTTPClient(&timeout)
 
-		req, err := http.NewRequest("GET", templateUrl, nil)
+		req, err := http.NewRequest(http.MethodGet, templateUrl, nil)
 		if err != nil {
 			log.Println(err.Error())
 			return err

proxy/deploy.go

@@ -60,10 +60,10 @@ func DeployFunction(fprocess string, gateway string, functionName string, image
 	timeout := 120 * time.Second
 	client := MakeHTTPClient(&timeout)
 
-	method := "POST"
+	method := http.MethodPost
 	// "application/json"
 	if update {
-		method = "PUT"
+		method = http.MethodPut
 	}
 
 	request, _ = http.NewRequest(method, gateway+"/system/functions", reader)

proxy/invoke.go

@@ -22,7 +22,7 @@ func InvokeFunction(gateway string, name string, bytesIn *[]byte, contentType st
 	var timeout *time.Duration
 	client := MakeHTTPClient(timeout)
 
-	postRequest, _ := http.NewRequest("POST", gateway+"/function/"+name, reader)
+	postRequest, _ := http.NewRequest(http.MethodPost, gateway+"/function/"+name, reader)
 	res, err := client.Do(postRequest)
 
 	if err != nil {

proxy/list.go

@@ -23,7 +23,7 @@ func ListFunctions(gateway string) ([]requests.Function, error) {
 	timeout := 120 * time.Second
 	client := MakeHTTPClient(&timeout)
 
-	getRequest, _ := http.NewRequest("GET", gateway+"/system/functions", nil)
+	getRequest, _ := http.NewRequest(http.MethodGet, gateway+"/system/functions", nil)
 	res, err := client.Do(getRequest)
 	if err != nil {
 		fmt.Println()

stack/stack.go

@@ -90,7 +90,7 @@ func ParseYAMLData(fileData []byte, regex string, filter string) (*Services, err
 
 // fetchYAML pulls in file from remote location such as GitHub raw file-view
 func fetchYAML(address *url.URL) ([]byte, error) {
-	req, err := http.NewRequest("GET", address.String(), nil)
+	req, err := http.NewRequest(http.MethodGet, address.String(), nil)
 	if err != nil {
 		return nil, err
 	}