adding comments from PR

x-pack/filebeat/docs/inputs/input-httpjson.asciidoc

@@ -205,6 +205,7 @@ Some built-in helper functions are provided to work with the input state inside
 - `div`: does the integer division of two integer values.
 - `hmac`: calculates the hmac signature of a list of strings concatenated together. Supports sha1 or sha256. Example `[[hmac "sha256" "secret" "string1" "string2" (formatDate (now) "RFC1123")]]`
 - `base64Encode`: Joins and base64 encodes all supplied strings. Example `[[base64Encode "string1" "string2"]]`
+- `base64EncodeNoPad`: Joins and base64 encodes all supplied strings without padding. Example `[[base64EncodeNoPad "string1" "string2"]]`
 
 In addition to the provided functions, any of the native functions for https://golang.org/pkg/time/#Time[`time.Time`], https://golang.org/pkg/net/http/#Header[`http.Header`], and https://golang.org/pkg/net/url/#Values[`url.Values`] types can be used on the corresponding objects. Examples: `[[(now).Day]]`, `[[.last_response.header.Get "key"]]`
 

x-pack/filebeat/input/httpjson/internal/v2/value_tpl.go

@@ -56,6 +56,7 @@ func (t *valueTpl) Unpack(in string) error {
 			"div":                 div,
 			"hmac":                hmacString,
 			"base64Encode":        base64Encode,
+			"base64EncodeNoPad":   base64EncodeNoPad,
 		}).
 		Delims(leftDelim, rightDelim).
 		Parse(in)
@@ -254,6 +255,15 @@ func base64Encode(values ...string) string {
 	return base64.StdEncoding.EncodeToString([]byte(data))
 }
 
+func base64EncodeNoPad(values ...string) string {
+	data := strings.Join(values, "")
+	if data == "" {
+		return ""
+	}
+
+	return base64.RawStdEncoding.EncodeToString([]byte(data))
+}
+
 func hmacString(hmacType string, hmacKey string, values ...string) string {
 	data := strings.Join(values[:], "")
 	if data == "" {