Trouble parsing remote RSS feed using ColdFusion

Question

I'm having a vexing time displaying a remote RSS feed on an intranet site. I'm using the MM_ XSLTransform.cfc version 0.6.2 to pull in the feed and a basic xsl to output. The feed url is www.fedsources.com/FedsourcesNet/RssFeeds/RSS_MarketFlash.aspx. If you open it in a browser, you'll see it appears to be an ordinary RSS feed. But when I try to display it in CF, I get the following" MM_ XSLTransform error. www.fedsources.com/FedsourcesNet/RssFeeds/RSS_ MarketFlash.aspx is not a valid XML document. Parsing www.fedsources.com/FedsourcesNet/RssFeeds/RSS_ MarketFlash.aspx An error occured while Parsing an XML document. Content is not allowed in prolog." (the actual error included http:// in the urls. Then the feed is dumped as part of the error message.
What's especially frustrating is if I view the source of the RSS and copy and paste it into a text file, then parse that text file, it displays fine. Running CF version 7.
I tried changing the charset from UTF-8 to windows-1252, but that added some weird characters at the beginning and didn't help. I also tried stripping out everything between <channel> and <item> but that didn't help.
I've successfully parsed other RSS feeds outside our firewall using the same code. Is there something about the aspx extension that's causing the error? Any thoughts? Anyone?
Thanks.

Answer 1

What's the exact code that you're using to parse the XML document? This particular error normally happens if you have some data before the <?xml?> tag in the document, even a single space can cause a problem.

I'm not familiar with the particular CFC you mentioned, so I can't troubleshoot that one for you, but make sure that you use the Trim function around any XML content you're going to try to parse.

UPDATE: A quick Google search led me to this post from Ben Nadel: http://www.bennadel.com/blog/1206-Content-Is-Not-Allowed-In-Prolog-ColdFusion-XML-And-The-Byte-Order-Mark-BOM-.htm

You need to remove the Byte-Order-Mark from the feed. This code works without an error:

<cfhttp method="get" url="http://www.fedsources.com/FedsourcesNet/RssFeeds/RSS_MarketFlash.aspx" />
<cfset xmlResult = XmlParse(REReplace( cfhttp.FileContent, "^[^<]*", "", "all" )) />
<cfdump var="#XMLParse(xmlResult)#" />