Add url tag only if not already set

plugins/inputs/http/README.md

@@ -20,9 +20,6 @@ The HTTP input plugin collects metrics from one or more HTTP(S) endpoints.  The
   # username = "username"
   # password = "pa$$word"
 
-  ## Tag all metrics with the url
-  # tag_url = true
-
   ## Optional SSL Config
   # ssl_ca = "/etc/telegraf/ca.pem"
   # ssl_cert = "/etc/telegraf/cert.pem"

plugins/inputs/http/http.go

@@ -24,9 +24,6 @@ type HTTP struct {
 	Username string
 	Password string
 
-	// Option to add "url" tag to each metric
-	TagURL bool `toml:"tag_url"`
-
 	// Path to CA file
 	SSLCA string `toml:"ssl_ca"`
 	// Path to host cert file
@@ -183,7 +180,7 @@ func (h *HTTP) gatherURL(
 	}
 
 	for _, metric := range metrics {
-		if h.TagURL {
+		if !metric.HasTag("url") {
 			metric.AddTag("url", url)
 		}
 		acc.AddFields(metric.Name(), metric.Fields(), metric.Tags(), metric.Time())

plugins/inputs/http/http_test.go

@@ -23,8 +23,7 @@ func TestHTTPwithJSONFormat(t *testing.T) {
 
 	url := fakeServer.URL + "/endpoint"
 	plugin := &plugin.HTTP{
-		URLs:   []string{url},
-		TagURL: true,
+		URLs: []string{url},
 	}
 	metricName := "metricName"
 	p, _ := parsers.NewJSONParser(metricName, nil, nil)