How to replace all anchor tags with a different anchor using regex in ColdFusion - regex

Question

I found a similar question here: Wrap URL within a string with a href tags using Coldfusion
But what I want to do is replace tags with a slightly modified version AFTER the user has submitted it to the server. So here is some typical HTML text that the user will submit to the server:
<p>Terminator Genisys is an upcoming 2015 American science fiction action film directed by Alan Taylor. You can find out more by clicking here</p>
What I want to do is replace the <a href=""> part with a new version which would be like this:
...
clicking here
So I'm just adding the text rel="nofollow noreferrer" to the tag.
I must match anchor tags that contain a href attribute with a URL, not just the URL string itself, because sometimes a user could just do this:
<p>Terminator Genisys is an upcoming 2015 American science fiction action film directed by Alan Taylor. You can find out more by http://www.imdb.com</p>
In which case I still only want to replace the tag. I don't want to touch the actual anchor text used even though it is a URL.
So how could I rewrite this Regex
#REReplaceNoCase(myStr, "(\bhttp://[a-z0-9\.\-_:~###%&/?+=]+)", "\1", "all")#
the other way round, where its selecting tags and replacing them with my modified text?

Answer 1

If you're willing, this is a really easy task for jQuery (client-side)
JSFiddle: http://jsfiddle.net/mz1rwo0u/
$(document).ready(function () {
$("a").each(function(e) {
if ($(this).attr('href').match(/^https?:\/\/(www\.)?imdb\.com/i)) {
$(this).attr('rel','nofollow noreferrer');
}});
});
(If you right click any of the imdb links and Inspect Element, you'll see the rel attribute is added to the imdb links. Note that View Source won't reflect the changes, but Inspect Element is the important part.)
If you want to effect every a link, you can do this.
$(document).ready(function () {
$("a").each(function(e) {
$(this).attr('rel','nofollow noreferrer');
});
});
Finally, you can also use a selector to narrow it down, you might have the content loading into a dom element with the id contentSection. You can do...
$(document).ready(function () {
$("#contentSection a").each(function(e) {
if ($(this).attr('href').match(/^https?:\/\/(www\.)?imdb\.com/i)) {
$(this).attr('rel','nofollow noreferrer');
}});
});
It's a bit tougher to reliably parse this in cold fusion without the possibility of accidentally adding it twice (without invoking a tool like jSoup) but the jQuery version is client-side and works by obtaining data from the DOM rather than trying to hot-wire into it (a jSoup implementation works similarly, creating a DOM-like structure you can work with).
When talking about client-side vs server-side, you have to consider the mythical user who doesn't have javascript enabled (or who turns it off with malicious intent). If this functionality is not mission-critical. I'd use JQuery to do it. I've used similar functionality to pop an alert box when the user clicks an outside link on one of my sites.
Here's a jSoup implementation, quick and dirty. jSoup is great for how it selects similarly to jQuery.
<cfscript>
jsoup = CreateObject("java", "org.jsoup.Jsoup");
HTMLDocument = jsoup.parse("<A href='http://imdb.com'>test</a> - <A href='http://google.com'>google</a>");
As = htmldocument.select("a");
for (link in As) {
if (reFindnoCase("^https?:\/\/(www\.)?imdb\.com",link.attr("href"))) {
link.attr("rel","nofollow noreferrer");
}
}
writeOutput(htmldocument);
</cfscript>