Thursday, April 13, 2017

ORDS Standalone and URI Rewrites

My last post How to add an NCSA style Access Log to ORDS Standalone explained what the ORDS standalone is and that is based on Eclipse Jetty.  Jetty offers far more than ORDS exposed in it's standalone.  There's a long list of all the features and configuration options listed in the documentation, http://www.eclipse.org/jetty/documentation/9.2.21.v20170120/

A recent question came up for doing URL rewrites.  Jetty does offer this as well.  To take advantage of it the same jetty-http.xml file from my last post just needs a few more lines of xml added.

This example will be just a simple one that rewrites /catalog to /ords/klrice/metadata-catalog/ The better usage of this would be to have / redirect into an APEX application or some home page of the application.

The full list of options are listed in the Jetty Documentation 
http://www.eclipse.org/jetty/documentation/9.2.21.v20170120/rewrite-handler.html



<?xml version="1.0"?>
<!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd">
<Configure id="Server" class="org.eclipse.jetty.server.Server">

<!-- REWRITE -->
  <Get id="oldhandler" name="handler"/>
  <Set name="handler">
   <New id="Rewrite" class="org.eclipse.jetty.rewrite.handler.RewriteHandler">
    <Set name="handler"><Ref refid="oldhandler"/></Set>
    <Set name="rewriteRequestURI"><Property name="rewrite.rewriteRequestURI" default="true"/></Set>
    <Set name="rewritePathInfo"><Property name="rewrite.rewritePathInfo" default="false"/></Set>
    <Set name="originalPathAttribute"><Property name="rewrite.originalPathAttribute" default="requestedPath"/></Set>
   </New>
  </Set>
  <Ref refid="Rewrite">
<!-- REWRITE of /catalog ---- /ords/klrice/metadata-catalog/ -->
<Call name="addRule"> <Arg> <New class="org.eclipse.jetty.rewrite.handler.RewritePatternRule"> <Set name="pattern">/catalog</Set> <Set name="replacement">/ords/klrice/metadata-catalog/</Set> </New> </Arg> </Call> </Ref>
<!-- HTTP ACCESS LOGS -->
  <Ref id="Handlers">
    <Call name="addHandler">
      <Arg>
        <New id="RequestLog" class="org.eclipse.jetty.server.handler.RequestLogHandler">
          <Set name="requestLog">
            <New id="RequestLogImpl" class="org.eclipse.jetty.server.NCSARequestLog">
              <Set name="filename"><Property name="jetty.logs" default="/tmp/"/>ords-access-yyyy_mm_dd.log</Set>
              <Set name="filenameDateFormat">yyyy_MM_dd</Set>
              <Set name="retainDays">90</Set>
              <Set name="append">true</Set>
              <Set name="extended">false</Set>
              <Set name="logCookies">false</Set>
              <Set name="LogTimeZone">GMT</Set>
            </New>
          </Set>
        </New>
      </Arg>
    </Call>
  </Ref>
</Configure>




The result is as expected.  This could be used for anything from shorter REST points like this catalog example or nicer entry points into APEX application.



The example for an APEX URL would be:

<!-- REWRITE of /awesomeapp ---- /ords/f?p=105:2:::::: -->

<Call name="addRule">
 <Arg>
   <New class="org.eclipse.jetty.rewrite.handler.RewritePatternRule">
     <Set name="pattern">/awesomeapp</Set>
     <Set name="replacement">/ords/f?p=105:2::::::/</Set>
   </New>
 </Arg>
</Call>