HTTP Entity: Difference between revisions

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==Entity Body Type==
==Entity Body Type==


When an entity body is included with a message, the data type of that body is determined via the header fields Content-Type and Content- Encoding. These define a two-layer, ordered encoding model:
When an entity body is included with a message, the data type of that body is determined from the entity header fields Content-Type and Content- Encoding. These define a two-layer, ordered encoding model:


<pre>
<pre>
entity-body = Content-Encoding(Content-Type(data) )
entity-body = Content-Encoding(Content-Type(data) )
</pre>
</pre>
Content-Type specifies the media type of the underlying data. Content-Encoding may be used to indicate any additional content codings applied to the data, usually for the purpose of data compression, that are a property of the requested resource. There is no default encoding.


Any HTTP/1.1 message containing an entity-body SHOULD include a Content-Type header field defining the media type of that body. If and only if the media type is not given by a Content-Type field, the recipient MAY attempt to guess the media type via inspection of its content and/or the name extension(s) of the URI used to identify the resource. If the media type remains unknown, the recipient SHOULD treat it as type "application/octet-stream".
Any HTTP/1.1 message containing an entity-body SHOULD include a Content-Type header field defining the media type of that body. If and only if the media type is not given by a Content-Type field, the recipient MAY attempt to guess the media type via inspection of its content and/or the name extension(s) of the URI used to identify the resource. If the media type remains unknown, the recipient SHOULD treat it as type "application/octet-stream".

Revision as of 04:08, 6 January 2017

External

Internal

Overview

The HTTP request/response may optionally transfer an entity. An entity consists of entity header fields, which are grouped together with the other headers of the request or response, and an entity-body.

The HTTP protocol requires that requests/response which include a body either use chunked transfer encoding or send a Content-Length request header.

Entity Headers

Entity Headers

Entity Body

https://www.w3.org/Protocols/rfc2616/rfc2616-sec7.html#sec7.2

The entity body (if any) sent with the HTTP request/response is in a format and encoding defined by the Entity Headers.

Entity Body Type

When an entity body is included with a message, the data type of that body is determined from the entity header fields Content-Type and Content- Encoding. These define a two-layer, ordered encoding model:

entity-body = Content-Encoding(Content-Type(data) )

Any HTTP/1.1 message containing an entity-body SHOULD include a Content-Type header field defining the media type of that body. If and only if the media type is not given by a Content-Type field, the recipient MAY attempt to guess the media type via inspection of its content and/or the name extension(s) of the URI used to identify the resource. If the media type remains unknown, the recipient SHOULD treat it as type "application/octet-stream".

Entity Body Length

7.2.2 Entity Length

The entity-length of a message is the length of the message-body before any transfer-codings have been applied. Section 4.4 defines how the transfer-length of a message-body is determined.