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ruby-on-railsrubyxpathhpricot

XPath and Hpricot -- works on some machines, not others?

The following hpricot code successfully extracts the STPeriods in the XML on two of my machines (Vista and an Ubuntu server) but fails on another Ubuntu laptop. All machines have Hpricot v0.82

Any ideas? Totally stumped.

Hpricot code:

  (doc/"WeatherFeed/Location/WxShortTerm/STPeriod").each do |ham_forecast|

XML file

<?xml version="1.0" encoding="ISO-8859-1" ?>
<WeatherFeed>
  <Location ID="EINN" name="Shannon Airport" state="" country="IE" tz="0" tzname="GMT">
    <Astro>
      <AstroPeriod Day="WED" Date="2009-12-16" Sunrise="8:41 AM GMT" Sunset="4:20 PM GMT" Moonrise="9:03 AM GMT" Moonset="4:02 PM GMT" MoonIllum="4%" MoonAge="0" MoonPhase="Waxing Crescent Moon" MoonIcon="1"/>
      <AstroPeriod Day="THU" Date="2009-12-17" Sunrise="8:42 AM GMT" Sunset="4:20 PM GMT" Moonrise="9:46 AM GMT" Moonset="5:05 PM GMT" MoonIllum="10%" MoonAge="1" MoonPhase="Waxing Crescent Moon" MoonIcon="1"/>
    </Astro>
    <WxOb StationID="EINN" TempC="7" TempF="45" ApparentC="5" ApparentF="41" DewPointC="6" DewPointF="43" RelativeHumidity="93" WindSpeedKnots="8" WindSpeedMPH="9" WindDirection="320" WindDirectionEng="NW" WindGustKnots="0" WindGustMPH="0" PressureMB="1013" PressureIN="29.88" Wx="Mostly Cloudy" Icon="mcloudyn.gif" Visibility="&gt;10km" VisibilityKM="16.09" VisibilityMI="10" ReportEpoch="1260999000" ReportDate="2009-12-16 21:30 UTC"/>
    <WxShortTerm ID="EINN">
      <STPeriod interval="1" Epoch="1261018800" Day="Thu" Date="2009-12-17" Time="03:00" Wx="Overcast" Icon="cloudyn.gif" TempC="6" TempF="42" Pop="0" QPFmm="0" QPFin="0" DewPointC="4.4" DewPointF="40" RelativeHumidity="92" WindSpeedKnots="12" WindSpeedMPH="14" WindDirectionEng="NE"/>
      <STPeriod interval="2" Epoch="1261029600" Day="Thu" Date="2009-12-17" Time="06:00" Wx="Mostly Cloudy" Icon="mcloudyn.gif" TempC="4" TempF="39" Pop="0" QPFmm="0" QPFin="0" DewPointC="3" DewPointF="37" RelativeHumidity="93" WindSpeedKnots="11" WindSpeedMPH="13" WindDirectionEng="NE"/>
      <STPeriod interval="3" Epoch="1261040400" Day="Thu" Date="2009-12-17" Time="09:00" Wx="Partly Cloudy" Icon="pcloudy.gif" TempC="2" TempF="36" Pop="0" QPFmm="0" QPFin="0" DewPointC="1.4" DewPointF="35" RelativeHumidity="95" WindSpeedKnots="10" WindSpeedMPH="12" WindDirectionEng="NE"/>
      <STPeriod interval="4" Epoch="1261051200" Day="Thu" Date="2009-12-17" Time="12:00" Wx="Partly Cloudy" Icon="pcloudy.gif" TempC="4" TempF="38" Pop="0" QPFmm="0" QPFin="0" DewPointC="1.6" DewPointF="35" RelativeHumidity="87" WindSpeedKnots="12" WindSpeedMPH="14" WindDirectionEng="NE"/>
      <STPeriod interval="5" Epoch="1261062000" Day="Thu" Date="2009-12-17" Time="15:00" Wx="Mostly Cloudy" Icon="mcloudy.gif" TempC="3" TempF="37" Pop="0" QPFmm="0" QPFin="0" DewPointC="1" DewPointF="34" RelativeHumidity="87" WindSpeedKnots="12" WindSpeedMPH="14" WindDirectionEng="NE"/>
      <STPeriod interval="6" Epoch="1261072800" Day="Thu" Date="2009-12-17" Time="18:00" Wx="Mostly Cloudy" Icon="mcloudyn.gif" TempC="3" TempF="37" Pop="0" QPFmm="0" QPFin="0" DewPointC="0.9" DewPointF="34" RelativeHumidity="89" WindSpeedKnots="12" WindSpeedMPH="14" WindDirectionEng="NE"/>
      <STPeriod interval="7" Epoch="1261083600" Day="Thu" Date="2009-12-17" Time="21:00" Wx="Mostly Cloudy" Icon="mcloudyn.gif" TempC="2" TempF="36" Pop="0" QPFmm="0" QPFin="0" DewPointC="0.2" DewPointF="32" RelativeHumidity="88" WindSpeedKnots="11" WindSpeedMPH="13" WindDirectionEng="NE"/>
      <STPeriod interval="8" Epoch="1261094400" Day="Fri" Date="2009-12-18" Time="00:00" Wx="Partly Cloudy" Icon="pcloudyn.gif" TempC="-0" TempF="32" Pop="0" QPFmm="0" QPFin="0" DewPointC="-2.1" DewPointF="28" RelativeHumidity="87" WindSpeedKnots="10" WindSpeedMPH="11" WindDirectionEng="NE"/>
    </WxShortTerm>
  </Location>
</WeatherFeed>
Solution

  • Since I couldn't find any enlightenment here or elsewhere, I switched from Hpricot to Nokigiri and it works flawlessly across all machines now. The APIs are almost exactly compatible so it only took <10minutes to switch over. Also, I get the feeling that Nokogiri is being more actively maintained although it doesn't have a dependency on libxml2.