Get-RSSFeed.ps1

<#

.SYNOPSIS 
Octbober 2015 Powershell.org Scripting Gamnes Puzzle entry

.DESCRIPTION 
This advanced function retrieves news feeds from the BBC. The vanilla command defaults to the BBC's "Top Stories" but may be directed to any feed among the popular feeds listed on this page: http://www.bbc.co.uk/news/10628494

.EXAMPLE 
This example displays the default feed by publishdate in list format

Get-RSSFeed | sort Publishdate -Descending | fl Headline,Description,Publishdate,Link


-------------------------- EXAMPLE 2 --------------------------

This example uses the -Uri parameter to retrieve the US & Canada feed

Get-RSSFeed -Uri http://feeds.bbci.co.uk/news/world/us_and_canada/rss.xml | sort Publishdate -Descending | fl Headline,Description,Publishdate,Link


-------------------------- EXAMPLE 3 --------------------------

This example uses the -ViewNewestStory parameter to launch in Internet Explorer the newest story from the Latin America feed

Get-RSSFeed -Uri http://feeds.bbci.co.uk/news/world/latin_america/rss.xml -ViewNewestStory

-------------------------- EXAMPLE 4 --------------------------

This example exports the default feed to a .csv file

Get-RSSFeed | export-csv c:\BBC_TopStories.csv -notypeinformation

-------------------------- EXAMPLE 5 --------------------------

This example displays the default feed Headlines and Publishdate in tabular format

Get-RSSFeed | ft Headline,Publishdate

.LINK 
http://powershell.org/wp/2015/10/03/october-2015-scripting-games-puzzle/

#>

function Get-RSSFeed
{
    param
    (
    $Uri,
    [switch]$ViewNewestStory
    )

    # url param
    if ($Uri)
    {
        # rss feed collection with defined url
        $feed = (Invoke-WebRequest -Uri $Uri).content
    }

    # no url param
    else
    {
        # rss feed collection default (top stories)
        $feed = (Invoke-WebRequest -Uri http://feeds.bbci.co.uk/news/rss.xml).content
    }

    # feed headlines
    $regexTitle = '(?ms)<title>(.+?)</title>'
    $feedTitle = ([regex]::Matches($feed,$regexTitle)| foreach {$_.groups[1].value -split "</title>, " }) | select  -Skip 2

    # feed descriptions
    $regexDescription  = '(?ms)<description>(.+?)</description>'
    $feedDescription  = ([regex]::Matches($feed,$regexDescription)| foreach {$_.groups[1].value -split "</title>, " }) | select  -Skip 1

    # feed urls
    $regexLink = '(?ms)<link>(.+?)</link>'
    $feedLink = ([regex]::Matches($feed,$regexLink)| foreach {$_.groups[1].value -split "</title>, " }) | select  -Skip 2

    # feed publish date/time
    $regexPubdate = '(?ms)<pubDate>(.+?)</pubDate>'
    $feedPubdate = ([regex]::Matches($feed,$regexPubdate)| foreach {$_.groups[1].value -split "</title>, " })

    # table builder
    [int]$selector = 0
    foreach ($title in $feedTitle)
    {
        $writeDescription  = $feedDescription[$selector]
        $writePubdate = [datetime]($feedPubdate[$selector]).substring(5)
        $writeLink = $feedLink[$selector]
        $title | Add-Member -Name  HeadLine -MemberType  NoteProperty -Value ($title)
        $title | Add-Member -Name  Description -MemberType  NoteProperty -Value ($writeDescription)
        $title | Add-Member -Name  Publishdate -MemberType  NoteProperty -Value ($writePubdate)
        $title | Add-Member -Name  Link -MemberType  NoteProperty -Value ($writeLink)
        $selector = $selector+1
    }

    # rss table
    $rssTable = $feedTitle | select Headline,Description,Publishdate,Link

    # view newest story param
    if ($viewNewestStory)
    {
        $newestStory = ($rssTable | Sort  Publishdate -Descending  | select -First 1).Link
        & "C:\Program Files\Internet Explorer\iexplore.exe" $newestStory
        break
    }

    # default output
    $rssTable
}