How to generate the next uidNumber - Solution

Question

The following is the express code to generate the next uidNumber for a UNIX account.
Just thought I would share some of my own work with you all
the first part is place in the derivation field for account.uidnumber and the second is the rule used
The rule expects two arguments 1) The resource to query i.e LDAP
2) The base number to search from.
I choose 200 because my accounts range from 200 - 800
<cond>
  <and>
    <notnull>
      <ref>accounts[$(res)].uidNumber</ref>
    </notnull>
    <isTrue>
      <ref>accountInfo.accounts[$(res)].created</ref>
    </isTrue>
  </and>
  <ref>accounts[$(res)].uidNumber</ref>
  <rule name='Rule Library:UNIX next uidNumber'>
    <argument name='resID' value='$(res)'/>
    <argument name='baseUidNumber' value='200'/>
  </rule>
</cond>
<block>
  <defvar name='num'>
    <ref>baseUidNumber</ref>
  </defvar>
  <defvar name='uidList'>
    <block>
      <set name='UIDNUM'/>
      <appendAll name='UIDNUM'>
        <dolist name='OBJ'>
          <invoke name='getResourceObjects' class='com.waveset.ui.FormUtil'>
            <ref>:display.session</ref>
            <s>User</s>
            <ref>resID</ref>
            <map>
              <s>searchFilter</s>
              <s>uidNumber=*</s>
              <s>searchAttrsToGet</s>
              <list>
                <s>uidNumber</s>
              </list>
            </map>
          </invoke>
          <get>
            <ref>OBJ</ref>
            <s>uidNumber</s>
          </get>
        </dolist>
      </appendAll>
      <ref>UIDNUM</ref>
    </block>
  </defvar>
  <while>
    <contains>
      <ref>uidList</ref>
      <expand>
        <s>$(num)</s>
      </expand>
    </contains>
    <set name='num'>
      <add>
        <ref>num</ref>
        <i>1</i>
      </add>
    </set>
  </while>
  <expand>
    <s>$(num)</s>
  </expand>
</block>The unqiue thing is that the expand tag is used to do some type conversion for the list comparision.
If you have betters ways to do this then let me know

Answer 1

I tackled this problem by using one of our Oracle databases. I created a sequence in the database, then wrote a rule that queried the next sequence value from the database. This sequence is also used by another process external to IDM to allocate uidnumbers. Using this method, there is no chance of collision.