You Give Love a Bad (Dot) Name

I have no idea why this information was so difficult to find, but I'm posting it here in case I ever need it again.

To do a reverse lookup in coldfusion:

<cfscript>
rawIP = createObject("java", "java.net.InetAddress").getByName('#ipaddress#').getAddress();
hostname = createObject("java", "java.net.InetAddress").getByAddress('#rawIP#').getHostName();
chostname = createObject("java", "java.net.InetAddress").getByAddress('#rawIP#').getCanonicalHostName();
</cfscript>

Note — this is slow. If you're doing them in bulk, you may need to go in small batches or set a higher timeout.

Also, this was perhaps useful: http://api.hostip.info/get_html.php?ip=#ipaddress#&position=true — returns the country, city, state, and geotag info for an IP address, where available.

Assumption: table named locations that has a location name and the location's latitude & longitude as a single field, with lat and lon comma separated, both in signed degrees format.

This is an intentional cartesian join… so if you have a lot of locations, use with care.

<cfquery datasource="MyDSN" name="getDist">
SELECT DISTINCT   
    a.latlon AS thestart,
    a.locName AS startname,
    b.latlon AS theend,
    b.locName AS endname
FROM     locations a
CROSS JOIN    locations b
WHERE     a.locName<> b.locName
ORDER BY     a.locName, b.locName
</cfquery>

<cfoutput query="getDist" group="startname">
<h4>#getDist.startname# to…</h4>
<ul><cfoutput>
<li>#getDist.endname# — #3963.0*acos(sin(listfirst(thestart)/57.295779513082323)*sin(listfirst(theend) / 57.295779513082323)+ cos(listfirst(thestart) / 57.295779513082323)*cos(listfirst(theend) / 57.295779513082323)*cos((listlast(theend) – listlast(thestart)) / 57.295779513082323))# Miles
</li>
</cfoutput>
</ul>
</cfoutput>

———————

This is based on a snippet of SQL code someone forwarded to me which was signed "RBarryYoung, 31-Jan-2009″ — so credit to RBarryYoung for it.