Why does this Python script only read the last RSS post into the file?

Question

Hi!

Im trying to fix a Python script which takes the posts from a specific RSS feed and strips them down and inputs them into a text file. As you can see beneath, there are two main print functions. One prints only to the shell once run, but it shows all of the posts, which is what I want it to do. Now, the second part is where the problem lies. It only prints out the last post of the RSS feed into a text, not the whole thing, as the first function does. I've also tried to make the second function (f = open()) the same way as the first with the %s instead of a new print-line pr. variable.

If anyone could tell me why the script doesnt post more than one (the last) post of the RSS feed into the text, but the whole thing in the shell, and what modifications I need to fix it, I would really appreciate it :)

Here is the code:

import urllib
import sys
import xml.dom.minidom

#The url of the feed
address = 'http://www.vg.no/export/Alle/rdf.hbs?kat=nyheter'

#Our actual xml document
document = xml.dom.minidom.parse(urllib.urlopen(address))
for item in document.getElementsByTagName('item'):
    title = item.getElementsByTagName('title')[0].firstChild.data
    link = item.getElementsByTagName('link')[0].firstChild.data
    description = item.getElementsByTagName('description')[0].firstChild.data

    str = link.strip("http://go.vg.no/cgi-bin/go.cgi/rssart/")
    print "\n"
    print "------------------------------------------------------------------"
    print '''"%s"\n\n%s\n\n(%s)''' % (title.encode('UTF8', 'replace'),
                                            description.encode('UTF8','replace'),
                                            str.encode('UTF8','replace'))
    print "------------------------------------------------------------------"
    print "\n"

f = open('lawl.txt','w')
print >>f, "----------------------Nyeste paa VG-------------------------------"
print >>f, title.encode('UTF8','replace')
print >>f, description.encode('UTF8','replace')
print >>f, str.encode('UTF8','replace')
print >>f, "------------------------------------------------------------------"
print >>f, "\n"

Answer 1

Your print >>f are after the for loop, so they are run once, and operate on the data that you last saved to title, description, and str.

You should open the file before the for loop and then put the print >>f lines inside the loop.

import urllib
import sys
import xml.dom.minidom

#The url of the feed
address = 'http://www.vg.no/export/Alle/rdf.hbs?kat=nyheter'

f = open('lawl.txt','w')

#Our actual xml document
document = xml.dom.minidom.parse(urllib.urlopen(address))
for item in document.getElementsByTagName('item'):
    title = item.getElementsByTagName('title')[0].firstChild.data
    link = item.getElementsByTagName('link')[0].firstChild.data
    description = item.getElementsByTagName('description')[0].firstChild.data

    str = link.strip("http://go.vg.no/cgi-bin/go.cgi/rssart/")
    print "\n"
    print "------------------------------------------------------------------"
    print '''"%s"\n\n%s\n\n(%s)''' % (title.encode('UTF8', 'replace'),
                                            description.encode('UTF8','replace'),
                                            str.encode('UTF8','replace'))
    print "------------------------------------------------------------------"
    print "\n"

    print >>f, "----------------------Nyeste paa VG-------------------------------"
    print >>f, title.encode('UTF8','replace')
    print >>f, description.encode('UTF8','replace')
    print >>f, str.encode('UTF8','replace')
    print >>f, "------------------------------------------------------------------"
    print >>f, "\n"

Answer 2

You iterate over all posts, assign their attributes to the variables and print to terminal.

Then you print the variables (which happen to hold the results of the last assignment) to file. So you get a single post here.

Need to iterate too if you want more than one.