Ismail

Use the shortcode `[recaptcha-protected-download]` to wrap any direct download link that you’d like reCaptcha to process.
`[recaptcha-protected-download]https://example.com/download.zip[/recaptcha-protected-download]`
Example
Here’s my `hello world` post HTML:
<pre>
Hello! This page is dynamically generated with my plugin called Content Generator which you can download from <a href="[recaptcha-protected-download]https://my-cdn.tld/static/content-generator.zip[/recaptcha-protected-download]">here</a>.

You can also download WordPress following <a href="[recaptcha-protected-download]https://wordpress.org/latest.zip[/recaptcha-protected-download]">this URL</a>
</pre>
Which is parsed as follows:
<pre>
Hello! This page is dynamically generated with my plugin called Content Generator which you can download from <a href="#rcpdl=371bce9996c0afc711648c2c4f3d5c97">here</a>.

You can also download WordPress following <a href="#rcpdl=7039e773658ed3c70d50e791ed4940fd">this URL</a>
</pre>
About
This plugin opts to generate fake links (anchors) controlled with JavaScript to open up a modal once clicked to opt users to complete the anti-spam test with <a href="https://github.com/google/recaptcha/" rel="nofollow ugc">Google reCaptcha</a>.
Once a user successfully submits a test, an AJAX callback will then verify the response and parse the download.
`md5` is used to hash the download links and fetch them later once a user submits a test.
You must provide your Google reCaptcha credentials which you can obtain from <a href="https://google.com/recaptcha/admin" rel="nofollow ugc">this page</a>
Once you activate the plugin, you should now navigate to “Settings” > “reCaptcha Downlaods” (or “Options” > “reCaptcha Downlaods” for network activated plugin) and add your Google reCaptcha credentials (public and private keys) which you can obtain from https://www.google.com/recaptcha/admin
The development version of this plugin is hosted on Github, feel free to fork it, contribute and improve it, or start a new issue if you want to report something like an unusual bug.
Here’s the Github repo: https://github.com/elhardoum/recaptcha-protected-downloads
Thank you!

reCaptcha Protected Downloads

Protect your downloads from bots and spiders with a shortcode and Google's no-captcha reCaptcha

Milan Dinić

Ryan Hellyer

Bjørn Johansen

Brian Layman

Stops automated spam while remaining as unobtrusive as possible to regular commenters. <a href="https://geek.hellyer.kiwi/products/spam-destroyer/" rel="nofollow ugc">The Spam Destroyer plugin</a> is intended to be effortless to use. Simply install, and enjoy a spam free website 🙂
<h3>Credits</h3>
<ul>
<li><a href="https://wordpress.org/support/users/omahoung/" rel="ugc">omahoung</a> – Bug reporting</li>
<li><a href="https://wordpress.org/support/profile/stromhalm" rel="ugc">Stromhalm</a> – Bug reporting</li>
<li><a href="http://ocaoimh.ie/" rel="nofollow ugc">Donncha O Caoimh</a> – Developer of Cookies for Comments, functionality of which is incorporated into Spam Destroyer</li>
<li><a href="http://elliottback.com/" rel="nofollow ugc">Elliot Back</a> – Developer of WP Hashcash, functionality of which is incorporated into Spam Destroyer</li>
<li><a href="http://nettsett.no/" rel="nofollow ugc">Marte Sollund and Ingvild Evje</a> – Bug reporting</li>
<li><a href="http://eHermitsInc.com/" rel="nofollow ugc">Brian Layman</a> – Code advice</li>
<li><a href="http://ronalfy.com/" rel="nofollow ugc">Ronald Huereca</a> – JS advice</li>
<li><a href="https://twitter.com/shawngaffney" rel="nofollow ugc">Shawn Gaffney</a> – Bug reporting</li>
<li><a href="http://konstruktors.com/" rel="nofollow ugc">Kaspars Dambis</a> – Bug reporting</li>
<li><a href="http://www.wanderingjon.com/" rel="nofollow ugc">Jon Brown</a> – Added error message filter</li>
</ul>

Spam Destroyer

Kills spam dead in it's tracks. Be gone evil demon spam!

reCaptcha Protected Downloads vs Spam Destroyer