Grabs all LinkedIn urls from a Coursera forum thread. Perfect for the "Let's Connect!" threads.

linkedInLinks.R

require(XML)
require(stringr)

#
# Grabs all LinkedIn urls from a Coursera forum thread. Perfect for the "Let's Connect!" threads.
# Usage:
# 1. Open a Coursera forum thread, containing LinkedIn links.
# 2. Scroll all the way to the bottom of the page to load all posts in the thread.
# 3. Save the web page to an html file named post.htm.
# 4. Call linkedInLinks("post.htm")
# 5. To save the result to a file: write.csv(linkedInLinks("post.htm"), "links.csv", quote=FALSE, row.names=FALSE)
#
linkedInLinks <- function(fileName) {
    # Read html page from file.
    data <- htmlTreeParse(fileName, useInternalNodes = T)
    
    # Find all linkedin links in the comments.
    commentElements <- xpathApply(data, "//div[@class='course-forum-post-text']//a[contains(@href, 'linkedin')]")
    
    # Get the href value for each link.
    sapply(commentElements, function(el) xmlGetAttr(el, "href"))
}