Basic script to import comments from a Apache Roller site to disqus.com.

roller_wxr_exporter.scala

#!/bin/sh
exec scala "$0" "$@"
!#

/*
Basic script to import comments from a Apache Roller site to disqus.com.
The script reads the entries and comments rss feeds from the roller website and generates a simple wxr file
that can be imported by disqus.com.

usage: roller_wxr_exporter.scala http://your_domain.com/your_blog
 */

import java.text.SimpleDateFormat
import scala.xml._
import java.net.URL
import java.io.FileWriter

if(argv.size != 1) {
  println("usage: roller_wxr_exporter.scala http://your_domain.com/your_blog")
  exit(1)
}

val uriBase = argv(0)

var commentId = 0
val dateFormatIn = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z")
val dateFormatOut = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")

val posts = XML.load(new URL(uriBase + "/feed/entries/rss"))
val comments = XML.load(new URL(uriBase + "/feed/comments/rss"))

val items = (posts \\ "item") flatMap(item => toItem(item, getComments(item).map(c => toWxrComment(c))))

val writer = new FileWriter("wxr.xml")
XML.write(writer, assembleWxr(posts, items), "UTF-8", true, null)
writer.close

def getComments(item: Node): NodeSeq = {
  val guid = (item \ "guid").text
  println(guid)
  (comments \\ "item").filter(c => (c \ "guid").text.replaceAll("#.*$", "") == guid)  
}

def toItem(item: Node, comments: NodeSeq) = {
  <item>
    <title>{ (item \ "title").text}</title>
    <link>{ (item \ "guid").text}</link>
    <pubDate>{ (item \ "pubDate").text}</pubDate>
    <description/>
    {comments}
  </item>
}

def toWxrComment(item: Node) = {
  commentId += 1
  val date = dateFormatIn.parse((item \ "pubDate").text)
  <wp:comment>
    <wp:comment_id>{commentId}</wp:comment_id>
    <wp:comment_author>{ (item \ "creator").text }</wp:comment_author>
    <wp:comment_author_email />
    <wp:comment_author_url />
    <wp:comment_author_ip />
    <wp:comment_date>{ dateFormatOut.format(date) }</wp:comment_date>
    <wp:comment_content>{ (item \ "description").text }</wp:comment_content>
    <wp:comment_approved>1</wp:comment_approved>
  </wp:comment>
}

def assembleWxr(rss: Elem, items: Seq[NodeSeq]) = {
  val channel = rss \\ "channel"
  
  <rss version="2.0"
	  xmlns:content="http://purl.org/rss/1.0/modules/content/"
	  xmlns:wfw="http://wellformedweb.org/CommentAPI/"
	  xmlns:dc="http://purl.org/dc/elements/1.1/"
	  xmlns:wp="http://wordpress.org/export/1.0/">

    <channel>
	    <title>{ (channel \ "title").text}</title>
	    <link>{ (channel \ "link").text}</link>
	    <description>{ (channel \ "description").text}</description>
	    <pubDate>{ (channel \ "pubDate").text}</pubDate>
	    <generator>roller_wxr_exporter</generator>
	    <language>en</language>

      {items}
   </channel>
 </rss>
}