Changeset 888

Timestamp:

Jul 23, 2010, 7:45:21 AM (9 years ago)

Author:

mnot@…

Message:

Define caching requirements for methods (see #139).

File:

• draft-ietf-httpbis/latest/p2-semantics.xml (modified) (6 diffs)

draft-ietf-httpbis/latest/p2-semantics.xml

@@ -76 +76 @@
   <!ENTITY p6-heuristic               "<xref target='Part6' x:rel='#heuristic.freshness'
 xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
+  <!ENTITY p6-explicit               "<xref target='Part6' x:rel='#calculating.freshness.lifetime'
+xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
+  <!ENTITY p6-combine               "<xref target='Part6' x:rel='#combining.headers'
+xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
 ]>
 <?rfc toc="yes" ?>
@@ -864 +868 @@
 </t>
 <t>
-   The response to a GET request is cacheable if and only if it meets
-   the requirements for HTTP caching described in &caching;.
+   The response to a GET request is cacheable and &MAY; be used to satisfy
+   subsequent GET and HEAD requests (see &caching;).
 </t>
 <t>
@@ -889 +893 @@
 </t>
 <t>
-   The response to a HEAD request &MAY; be cacheable in the sense that the
-   information contained in the response &MAY; be used to update a
-   previously cached representation from that resource. If the new field values
+   The response to a HEAD request is cacheable and &MAY; be used to satisfy
+   a subsequent HEAD request; see &caching;. It also &MAY; be used to update a previously cached
+   representation from that resource; if the new field values
    indicate that the cached representation differs from the current representation (as
    would be indicated by a change in Content-Length, Content-MD5, ETag
@@ -942 +946 @@
 </t>
 <t>
-   Responses to this method are not cacheable, unless the response
-   includes appropriate Cache-Control or Expires header fields. However,
-   the 303 (See Other) response can be used to direct the user agent to
-   retrieve a cacheable resource.
+   Responses to POST requests are cacheable only when they
+   include explicit freshness information (see &p6-explicit;). Such 
+   cached POST responses &MAY; be used to satisfy subsequent GET and 
+   HEAD requests. Note that POST caching is not widely implemented. 
+   However, the 303 (See Other) response can be used to direct the 
+   user agent to retrieve a cacheable resource.
 </t>
 </section>
@@ -1039 +1045 @@
    If the request passes through a cache and the Effective Request URI
    identifies one or more currently cached representations, those entries &SHOULD; be
-   treated as stale. Responses to the DELETE method &MUST-NOT; be cached.
+   treated as stale. Responses to the DELETE method are not cacheable.
 </t>
 </section>
@@ -1071 +1077 @@
    "message/http" (see &media-type-message-http;) and contain a message-body
    that encloses a copy of the entire request message.
-   Responses to the TRACE method &MUST-NOT; be cached.
+   Responses to the TRACE method are not cacheable.
 </t>
 </section>