Add support for sending a request body to http input (#5074)

plugins/inputs/http/http.go

@@ -3,6 +3,7 @@ package http
 import (
 	"errors"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"net/http"
 	"strings"
@@ -17,17 +18,19 @@ import (
 )
 
 type HTTP struct {
-	URLs   []string `toml:"urls"`
-	Method string
+	URLs            []string `toml:"urls"`
+	Method          string   `toml:"method"`
+	Body            string   `toml:"body"`
+	ContentEncoding string   `toml:"content_encoding"`
 
-	Headers map[string]string
+	Headers map[string]string `toml:"headers"`
 
 	// HTTP Basic Auth Credentials
-	Username string
-	Password string
+	Username string `toml:"username"`
+	Password string `toml:"password"`
 	tls.ClientConfig
 
-	Timeout internal.Duration
+	Timeout internal.Duration `toml:"timeout"`
 
 	client *http.Client
 
@@ -52,6 +55,13 @@ var sampleConfig = `
   # username = "username"
   # password = "pa$$word"
 
+  ## HTTP entity-body to send with POST/PUT requests.
+  # body = ""
+
+  ## HTTP Content-Encoding for write request body, can be set to "gzip" to
+  ## compress body or "identity" to apply no encoding.
+  # content_encoding = "identity"
+
   ## Optional TLS Config
   # tls_ca = "/etc/telegraf/ca.pem"
   # tls_cert = "/etc/telegraf/cert.pem"
@@ -132,11 +142,20 @@ func (h *HTTP) gatherURL(
 	acc telegraf.Accumulator,
 	url string,
 ) error {
-	request, err := http.NewRequest(h.Method, url, nil)
+	body, err := makeRequestBodyReader(h.ContentEncoding, h.Body)
 	if err != nil {
 		return err
 	}
 
+	request, err := http.NewRequest(h.Method, url, body)
+	if err != nil {
+		return err
+	}
+
+	if h.ContentEncoding == "gzip" {
+		request.Header.Set("Content-Encoding", "gzip")
+	}
+
 	for k, v := range h.Headers {
 		if strings.ToLower(k) == "host" {
 			request.Host = v
@@ -183,6 +202,18 @@ func (h *HTTP) gatherURL(
 	return nil
 }
 
+func makeRequestBodyReader(contentEncoding, body string) (io.Reader, error) {
+	var err error
+	var reader io.Reader = strings.NewReader(body)
+	if contentEncoding == "gzip" {
+		reader, err = internal.CompressWithGzip(reader)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return reader, nil
+}
+
 func init() {
 	inputs.Add("http", func() telegraf.Input {
 		return &HTTP{