The Trailer response header allows the sender to include additional fields at the end of chunked messages in order to supply metadata that might be dynamically generated while the message body is sent, such as a message integrity check, digital signature, or post-processing status.
Note: The TE request header needs to be set to "trailers" to allow trailer fields.
| Header type | Request header, Response header, Payload header |
|---|---|
| Forbidden header name | yes |
Trailer: header-names
header-names
HTTP header fields which will be present in the trailer part of chunked messages. These header fields are disallowed:
Transfer-Encoding and Content-Length),Host),Cache-Control, Max-Forwards, or TE),Authorization or Set-Cookie),Content-Encoding, Content-Type, Content-Range, and Trailer itself.In this example, the Expires header is used at the end of the chunked message and serves as a trailing header.
HTTP/1.1 200 OK
Content-Type: text/plain
Transfer-Encoding: chunked
Trailer: Expires
7\r\n
Mozilla\r\n
9\r\n
Developer\r\n
7\r\n
Network\r\n
0\r\n
Expires: Wed, 21 Oct 2015 07:28:00 GMT\r\n
\r\n
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
Trailer |
Yes
|
12
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
Yes
|
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https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Trailer