Commit 59d65279 authored by Ruediger Pluem's avatar Ruediger Pluem
Browse files

* Add the following environment variables to expose the information 

* about
  the route, the sticky session and the worker used during a request to
  other modules:

  BALANCER_SESSION_STICKY
  BALANCER_SESSION_ROUTE
  BALANCER_NAME
  BALANCER_WORKER_NAME
  BALANCER_WORKER_ROUTE

PR: 39806
Submitted by: Brian <brectanu gmail.com>
Reviewed by: rpluem


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@417238 13f79535-47bb-0310-9956-ffa450edef68
parent 73a73ea2

CHANGES

+4 −0
Original line number Diff line number Diff line
@@ -2,6 +2,10 @@ 
Changes with Apache 2.3.0

  [Remove entries to the current 2.0 and 2.2 section below, when backported]













  *) mod_proxy_balancer: Add information about the route, the sticky session













     and the worker used during a request as environment variables. PR 39806.













     [Brian <brectanu gmail.com>]



























  *) mod_isapi: Avoid double trailing slashes in HSE_REQ_MAP_URL_TO_PATH















     support.  Also corrects the slashes for Windows.  PR 15993  [William Rowe]















































docs/manual/mod/mod_proxy_balancer.xml



+41
−0






























Original line number
Diff line number
Diff line








@@ -271,6 +271,47 @@ candidate lbstatus -= total factor</code></pre>





























</section>





























<section id="environment">













    <title>Exported Environment Variables</title>













    <p>At present there are 5 environment variables exported:</p>













    













    <!-- ============= BALANCER_SESSION_STICKY =============== -->













    <dt><var><a name="balancer_session_sticky" id="balancer_session_sticky">BALANCER_SESSION_STICKY</a></var></dt>













    <dd>













    <p>This is assigned the <var>stickysession</var> value used in the current













    request.  It is the cookie or parameter name used for sticky sessions</p>













    </dd>



























    <!-- ============= BALANCER_SESSION_ROUTE ================ -->













    <dt><var><a name="balancer_session_route" id="balancer_session_route">BALANCER_SESSION_ROUTE</a></var></dt>













    <dd>













    <p>This is assigned the <var>route</var> parsed from the current 













    request.</p>













    </dd>



























    <!-- ============= BALANCER_NAME ========================= -->













    <dt><var><a name="balancer_name" id="balancer_name">BALANCER_NAME</a></var></dt>













    <dd>













    <p>This is assigned the name of the balancer used for the current 













    request. The value is something like <code>balancer://foo</code>.</p>













    </dd>



























    <!-- ============= BALANCER_WORKER_NAME ================== -->













    <dt><var><a name="balancer_worker_name" id="balancer_worker_name">BALANCER_WORKER_NAME</a></var></dt>













    <dd>













    <p>This is assigned the name of the worker used for the current request.













    The value is something like <code>http://hostA:1234</code>.</p>













    </dd>



























    <!-- ============= BALANCER_WORKER_ROUTE ================= -->













    <dt><var><a name="balancer_worker_route" id="balancer_worker_route">BALANCER_WORKER_ROUTE</a></var></dt>













    <dd>













    <p>This is assigned the <var>route</var> of the worker that will be 













    used for the current request.</p>













    </dd>



























</section>





























<section id="enable">















    <title>Enabling Balancer Manager Support</title>















    <p>This module <em>requires</em> the service of 

































modules/proxy/mod_proxy_balancer.c



+14
−0






























Original line number
Diff line number
Diff line








@@ -389,6 +389,14 @@ static int proxy_balancer_pre_request(proxy_worker **worker,













        *worker = runtime;















    }





























    /* Add balancer/worker info to env. */













    apr_table_setn(r->subprocess_env,













                   "BALANCER_NAME", (*balancer)->name);













    apr_table_setn(r->subprocess_env,













                   "BALANCER_WORKER_NAME", (*worker)->name);













    apr_table_setn(r->subprocess_env,













                   "BALANCER_WORKER_ROUTE", (*worker)->s->route);





























    /* Rewrite the url from 'balancer://url'















     * to the 'worker_scheme://worker_hostname[:worker_port]/url'















     * This replaces the balancers fictional name with the









@@ -399,6 +407,12 @@ static int proxy_balancer_pre_request(proxy_worker **worker,













    if (route) {















        apr_table_setn(r->notes, "session-sticky", (*balancer)->sticky);















        apr_table_setn(r->notes, "session-route", route);



























        /* Add session info to env. */













        apr_table_setn(r->subprocess_env,













                       "BALANCER_SESSION_STICKY", (*balancer)->sticky);













        apr_table_setn(r->subprocess_env,













                       "BALANCER_SESSION_ROUTE", route);















    }















    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,















                 "proxy: BALANCER (%s) worker (%s) rewritten to %s",