Razvan Stanga

Complete WordPress Varnish Cache 3.x/4.x/5.x and Nginx Proxy Cache integration.
This plugin handles all integration with Varnish Cache and Nginx Proxy Cache. It was designed for high traffic websites.
Main features
<ul>
<li>admin interface, see screenshots</li>
<li>console for manual purges, supports regular expressions so you can purge an entire folder or just a single file</li>
<li>supports every type of Varnish Cache implementation, see screenshots for examples</li>
<li>unlimited number of Varnish Cache servers</li>
<li>use of custom headers when communicating with Varnish Cache does not interfere with other caching plugins, cloudflare, etc</li>
<li>Varnish Cache configuration generator</li>
<li>purge key method so you don’t need to setup ACLs</li>
<li>debugging</li>
<li>actively maintained</li>
</ul>
You can control the following from the Varnish Caching admin panel :
<ul>
<li>Enable/Disable caching</li>
<li>Homepage cache TTL</li>
<li>Cache TTL (for every other page)</li>
<li>IPs/Hosts to clear cache to support every type of Varnish Cache implementation</li>
<li>Override default TTL in posts/pages</li>
<li>Purge key based PURGE</li>
<li>Logged in cookie</li>
<li>Debugging option</li>
<li>console for precise manual purges</li>
</ul>
This plugin also auto purges Varnish Cache / Nginx Proxy Cache when your site is modified.
Varnish Caching sends a PURGE request to Varnish Cache / Nginx Proxy Cache when a page or post is modified. This occurs when editing, publishing, commenting or deleting an item, and when changing themes. 
Not all pages are purged every time, depending on your Varnish / Nginx Proxy Cache configuration. When a post, page, or custom post type is edited, or a new comment is added, only the following pages will purge:
<ul>
<li>The front page</li>
<li>The post/page edited</li>
<li>Any categories or tags associated with the page</li>
</ul>
<a href="https://www.varnish-cache.org/" rel="nofollow ugc">Varnish Cache</a> / <a href="https://www.nginx.com/blog/nginx-caching-guide/" rel="nofollow ugc">Nginx Proxy Cache</a> is a web application accelerator also known as a caching HTTP reverse proxy. You install it in front of any server that speaks HTTP and configure it to cache the contents. This plugin does not install Varnish/Nginx for you, nor does it configure Varnish/Nginx for WordPress. It’s expected you already did that on your own using the provided config files.
Inspired from the following :
<ul>
<li>https://wordpress.org/plugins/varnish-http-purge/</li>
<li>https://github.com/dreamhost/varnish-vcl-collection/</li>
</ul>

Varnish/Nginx Proxy Caching

Wordpress Varnish Cache 3.x/4.x/5.x and Nginx Proxy Cache integration

Smartpixels

Arul

<a href="http://www.smartpixels.net/?post_type=products&p=628" rel="nofollow ugc">Smart Varnish</a> A simple plugin to bypass varnish caching for logged in users and serve uncached content.
Useful for websites that don’t want to serve cached content for logged in users and at the same time want to serve cached content to guests.
NOTE: This plugin requires knowledge of varnish caching and server administration, it will not work out of the box. We cannot guarantee it will work in every scenario and recommend usage with discretion.
Please follow the <a href="http://www.smartpixels.net/?p=650" rel="nofollow ugc">tutorial here</a>.

Varnish/Nginx Proxy Caching vs Smart Varnish