How do I use Sun Web Server 7.0u1 reverse proxy to change public URLs?

Question

Some of our installations use the Sun Web Server 7.0 (update 1, usually)
for hosting some of the public resource and reverse-proxying other parts
of the URI namespace from other backend servers (content, application
and other types of servers).
So far every type of backend server served a unique part of the namespace
and there was no collision of names, and the backend resources were
published in a one-to-one manner. That is, a backend resource like, say,
http://appserver:8080/content/page.html would be published in the internet
as http://www.publicsite.com/content/page.html
I was recently asked to research whether we can rename some parts of
the public URI namespace, to publish some or all resources as, say,
http://www.publicsite.com/data/page.html while using the same backend
resources.
Another quest, possibly related in solution, was to make a tidy url for the
first page the user opens of the site. That is, in the current solution when
a visitor types the url "www.publicsite.com" in his or her browser, our web
server returns an HTTP-302 redirect to the actual first page URL, so the
browser sends a second request (and changes the URL in its location bar).
One customer said that it is not "tidy". They don't want the URL to change
right upon first rendering the page. They want the root page to be rendered
instantly i the first HTTP request.
So far I found that I can't solve these problems. I believe these problems
share a solution because it relies on ability to control the actual URI strings
requested by Sun Web Server from backend servers.
Some details follow, now:
It seems that the reverse proxy (Service fn="service-passthrough") takes
only the $uri value which was originally requested by the browser. I didn't
yet manage to override this value while processing a request, not even if
I "restart" a request. Turning the error log up to "finest" I see that even
when making the "service-passthrough" operation, the Sun Web Server
still remembers that the request was for "/test" (in my test case below);
it does indeed ask the backend server for an URI "/test" and that fails.
[04/Mar/2009:21:45:34] finest (25095) www.publicsite.com: for host xx.xx.xx.83
trying to GET /content/MainPage.html while trying to GET /test, func_exec reports:
fn="service-passthrough" rewrite-host="true" rewrite-location="true"
servers="http://10.16.2.127:8080" Directive="Service" DaemonPool="2b1348"
returned 0 (REQ_PROCEED)My obj.conf file currently has simple clauses like this:
# this causes /content/* to be taken from another (backend) server
NameTrans fn="assign-name" from="/content" name="content-test" nostat="/content"
# this causes requests to site root to be HTTP-redirected to a certain page URI
<If $uri =~ '^/$'>
    NameTrans fn="redirect"
        url="http://www.publicsite.com/content/MainPage.html"
</If>
<Object name="content-test">
### This maps http://public/content/* to http://10.16.2.127:8080/content/*
### Somehow the desired solution should instead map http://public/data/* to http://10.16.2.127:8080/content/*
    Service fn="service-passthrough" rewrite-host="true" rewrite-location="true" servers="http://10.16.2.127:8080"
    Service fn="set-variable" set-srvhdrs="host=www.publicsite.com:80"
</Object>
I have also tried "restart"ing the request like this:
    NameTrans fn="restart" uri="/data"or desperately trying to set the new request uri like this:
    Service fn="set-variable"  uri="/magnoliaPublic/Main.html"Thanks for any ideas (including a statement whether this can be done at all
in some version of Sun Web Server 7.0 or its opensourced siblings) ;)
//Jim

Answer 1

Some of our installations use the Sun Web Server 7.0 (update 1, usually)please plan on installing the latest service pack - 7.0 Update 4. these updates addresses potentially critical bug fixes.
I was recently asked to research whether we can rename some parts of
the public URI namespace, to publish some or all resources as, say,
http://www.publicsite.com/data/page.html while using the same backend
resources.> now, if all the resources are under say /data, then how will you know which pages need to be sent to which back end resources. i guess, you probably meant to check for /data/page.html should go to <back-end>/content/page.html
yes, you could do something like
- edit your corresponding obj.conf (<hostname>-obj.conf or obj.conf depending on your configuration)
<Object name=¨default¨>
<If $uri = ¨/page/¨>
#move this nametrans SAF (for map directive - which is for reverse proxy within <if> clause)
NameTrans.. fn=map
</If
</Object>
and you could do https-<hostname>/bin/reconfig (dynamic reconfiguration) to check out if this is what you wanted. also, you might want to move config/server.xml <log-level> to finest and do your configuration . this way, you would get enough information on what is going on within your server logs.
finally,when you are satisfied, you might have to run the following command to make your manual change into admin config repository.
<install-root>/bin/wadm pull-config user=admin config=<hostname> <hostname>
<install-root>/bin/wadm deploy-config --user=admin <hostname>
you might want to check out this for more info on how you could use <if> else condition to handle your requirement.
http://docs.sun.com/app/docs/doc/820-6599/gdaer?a=view
finally, you might want to refer to this doc - which explains on ws7 request processing overview. this should provide you with some pointers as to what these different directives mean
http://docs.sun.com/app/docs/doc/820-6599/gbysz?a=view
>
One customer said that it is not "tidy". They don't want the URL to change
right upon first rendering the page. They want the root page to be rendered
instantly i the first HTTP request.
please check out the rewrite / restart SAF. this should help you.
http://docs.sun.com/app/docs/doc/820-6599/gdada?a=view
pl. understand that - like with more web servers - ordering of directives is very important within obj.conf. so, you might want to make sure that you verify the obj.conf directive ordering is what you want it to do..
It seems that the reverse proxy (Service fn="service-passthrough") takes
only the $uri value which was originally requested by the browser. I didn't
yet manage to override this value while processing a request, not even if
I "restart" a request. Turning the error log up to "finest" I see that even
when making the "service-passthrough" operation, the Sun Web Server
still remembers that the request was for "/test" (in my test case below);
it does indeed ask the backend server for an URI "/test" and that fails.
now, you are in the totally wrong direction. web server 7 includes a highly integrated reverse proxy solution compared to 6.1. unlike 6.1, you don´t have to download a separate plugin . however, you will need to manually migrate your 6.1 based reverse proxy settings into 7.0. please check out this blog link on how to set up a reverse proxy
http://blogs.sun.com/amit/entry/setting_up_a_reverse_proxy
feel free to post to us if you need any futher help
you are probably better off - starting fresh
- install ws7u4
- use gui or CLI to create a reverse proxy and map one on one - say content
http://docs.sun.com/app/docs/doc/820-6601/create-reverse-proxy-1?a=view
if you don´t plan on using ws7 integrated web container (ability to process jsp/servlet), then you could disable java support as well. this should reduce your server memory footprint
<install-root>/bin/wadm disable-java user=admin config=<hostname>
<install-root>/bin/wadm create-reverse-proxy user=admin uri-prefix=/content server=<http://your back end server/ config=<hostname> --vs=<hostname>
<install-root>/bin/wadm deploy-config --user=admin <hostname>
now, you can check out the regular express processing and <if> syntax from our docs and try it out within <https-<hostname>/config/<hostname>-obj.conf> file and restart the server. pl. note that once you disable java, ws7 admin server creates <vs>-obj.conf and you need to edit this file and not default obj.conf for your changes to be read by server.
>
I have also tried "restart"ing the request like this:
NameTrans fn="restart" uri="/data"
ordering is very important here... you need to do this some thing like
<Object name=default>
<If not $restarted>
NameTrans fn=restart uri from=/¨ uri=/foo.
</If>