Support custom success codes in http input (influxdata#6549)

etc/telegraf.conf

@@ -2604,6 +2604,9 @@
 #   ## Amount of time allowed to complete the HTTP request
 #   # timeout = "5s"
 #
+#   ## List of success status codes
+#   # success_status_codes = [200]
+#
 #   ## Data format to consume.
 #   ## Each data format has its own unique set of configuration options, read
 #   ## more about them here:

plugins/inputs/http/README.md

@@ -40,6 +40,9 @@ The HTTP input plugin collects metrics from one or more HTTP(S) endpoints.  The
   ## Amount of time allowed to complete the HTTP request
   # timeout = "5s"
 
+  ## List of success status codes
+  # success_status_codes = [200]
+
   ## Data format to consume.
   ## Each data format has its own unique set of configuration options, read
   ## more about them here:

plugins/inputs/http/http.go

@@ -29,6 +29,8 @@ type HTTP struct {
 	Password string `toml:"password"`
 	tls.ClientConfig
 
+	SuccessStatusCodes []int `toml:"success_status_codes"`
+
 	Timeout internal.Duration `toml:"timeout"`
 
 	client *http.Client
@@ -71,6 +73,9 @@ var sampleConfig = `
   ## Amount of time allowed to complete the HTTP request
   # timeout = "5s"
 
+  ## List of success status codes
+  # success_status_codes = [200]
+
   ## Data format to consume.
   ## Each data format has its own unique set of configuration options, read
   ## more about them here:
@@ -101,6 +106,11 @@ func (h *HTTP) Init() error {
 		},
 		Timeout: h.Timeout.Duration,
 	}
+
+	// Set default as [200]
+	if len(h.SuccessStatusCodes) == 0 {
+		h.SuccessStatusCodes = []int{200}
+	}
 	return nil
 }
 
@@ -171,12 +181,19 @@ func (h *HTTP) gatherURL(
 	}
 	defer resp.Body.Close()
 
-	if resp.StatusCode != http.StatusOK {
-		return fmt.Errorf("Received status code %d (%s), expected %d (%s)",
+	responseHasSuccessCode := false
+	for _, statusCode := range h.SuccessStatusCodes {
+		if resp.StatusCode == statusCode {
+			responseHasSuccessCode = true
+			break
+		}
+	}
+
+	if !responseHasSuccessCode {
+		return fmt.Errorf("received status code %d (%s), expected any value out of %v",
 			resp.StatusCode,
 			http.StatusText(resp.StatusCode),
-			http.StatusOK,
-			http.StatusText(http.StatusOK))
+			h.SuccessStatusCodes)
 	}
 
 	b, err := ioutil.ReadAll(resp.Body)

plugins/inputs/http/http_test.go

@@ -106,6 +106,30 @@ func TestInvalidStatusCode(t *testing.T) {
 	require.Error(t, acc.GatherError(plugin.Gather))
 }
 
+func TestSuccessStatusCodes(t *testing.T) {
+	fakeServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusAccepted)
+	}))
+	defer fakeServer.Close()
+
+	url := fakeServer.URL + "/endpoint"
+	plugin := &plugin.HTTP{
+		URLs:               []string{url},
+		SuccessStatusCodes: []int{200, 202},
+	}
+
+	metricName := "metricName"
+	p, _ := parsers.NewParser(&parsers.Config{
+		DataFormat: "json",
+		MetricName: metricName,
+	})
+	plugin.SetParser(p)
+
+	var acc testutil.Accumulator
+	plugin.Init()
+	require.NoError(t, acc.GatherError(plugin.Gather))
+}
+
 func TestMethod(t *testing.T) {
 	fakeServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if r.Method == "POST" {