A proxy cache in front of Zope relies on the application providing explicit Last-Modified, Expires and Cache-Control headers.
This is currently not activated by default. In fact, Last-Modified and Expires are provided by CPSPortlets, but only on the first request on a document or section. Ex:
fermigier@ubuntu:~/tmp$ wget -S http://localhost:8080/cps/sections/test
--12:36:38-- http://localhost:8080/cps/sections/test
=> `test'
Resolving localhost... 127.0.0.1
Connecting to localhost|127.0.0.1|:8080... connected.
HTTP request sent, awaiting response...
HTTP/1.0 200 OK
Server: Zope/(Zope 2.9.2-, python 2.4.2, linux2) ZServer/1.1 CPS/3.4
Date: Wed, 19 Apr 2006 12:36:39 GMT
Content-Length: 17685
Expires: Wed, 19 Apr 2006 12:36:39 GMT
Last-Modified: Wed, 19 Apr 2006 12:36:39 GMT
Connection: Keep-Alive
Content-Type: text/html; charset=ISO-8859-15
Length: 17,685 (17K) [text/html]
100%[====================================>] 17,685 --.--K/s
12:36:39 (89.24 MB/s) - `test' saved [17685/17685]
fermigier@ubuntu:~/tmp$ wget -S http://localhost:8080/cps/sections/test
--12:36:42-- http://localhost:8080/cps/sections/test
=> `test.1'
Resolving localhost... 127.0.0.1
Connecting to localhost|127.0.0.1|:8080... connected.
HTTP request sent, awaiting response...
HTTP/1.0 200 OK
Server: Zope/(Zope 2.9.2-, python 2.4.2, linux2) ZServer/1.1 CPS/3.4
Date: Wed, 19 Apr 2006 12:36:43 GMT
Content-Length: 17685
Content-Type: text/html; charset=ISO-8859-15
Connection: Keep-Alive
Length: 17,685 (17K) [text/html]
100%[====================================>] 17,685 --.--K/s
12:36:43 (95.83 MB/s) - `test.1' saved [17685/17685]
