Mid-last year, Electronic Freedom Frontier announced Let’s Encrypt: free, automated, Open Source HTTPS Certificate Authority for everyone. That’s the padlock in the address bar. Supernaut and other sites of mine have either gone the parasitic paid route, or the “whole day lost and still not working” free route.

DreamHost, who has been my webhost for close to a decade (thanks Emile), announced in December they would be providing One-Click Let’s Encrypt setup for everyone, no matter what their hosting plan. Yesterday it arrived; It really is one-Click! Ok, two clicks, one checkbox, one select. Four things you have to do in DreamHost panel for what used to cost tens to hundreds of dollars/euros a year and hours of pain if you didn’t want to pay.

Awesome. Best thing that’s happened to the internet since ages.

Anyway, this isn’t about all that, it’s about “I have a WordPress site and how do I make the green padlock appear?” Cos that’s a couple more steps. Call it 15 minutes if you’re paying attention; an hour if you’re drinking.

So, you’ve already added the certificate in DreamHost Panel. No? To the DreamHost Wiki! Done that, wait for the confirmation email (might take a couple of hours), and on to your webserver.

I start with getting wp-admin all https-ified. Open your site in whatever FTP client you’re using, open wp-config.php and add:

define( 'FORCE_SSL_ADMIN', true );

Re-login to wp-admin, and check for the padlock in the address bar. Open Web Inspector (command-alt-i), select the Console tag and check for Mixed Content errors. Unless you’re doing weird things in wp-admin, that’s that side of things sorted.

In your site root directory, you’ll see a directory called “.well-known”. That’s added by Let’s Encrypt. Probably don’t want to delete that.

Open your root .htaccess and add two chunks of code:

# force redirect http to https
# ---------------------------------------------------------------

<IfModule mod_rewrite.c>
 RewriteEngine On
 RewriteCond %{HTTPS} off
 RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
</IfModule>

# https security headers
# http strict transport security (hsts)
# X-Xss-Protection
# X-Frame-Options
# X-Content-Type-Options
# ---------------------------------------------------------------

<IfModule mod_headers.c>
 Header always set Strict-Transport-Security "max-age=16070400; includeSubDomains"
 Header always set X-Xss-Protection "1; mode=block"
 Header always set X-Frame-Options "SAMEORIGIN"
 Header always set X-Content-Type-Options "nosniff"
 #Header always set Content-Security-Policy "default-src https://website.tld:443;"
</IfModule>

The first force redirects any requests for http to https. The second does some fairly obtuse header security stuff. You can read about that on securityheaders.io. (The Content Security Policy stuff takes a lot of back-and-forth to not cause chaos. Even wp-admin requires specific rules as it uses Google Fonts. Expect to lose at least an hour on that if you decide to set that up.)

Other ways of doing this are possible. It’s kinda unclear what’s canonical and what’s depricated, but WordPress Codex and elsewhere have variations on these (definite rabbithole, this stuff):

SSLOptions +StrictRequire
SSLRequireSSL
SSLRequire %{HTTP_HOST} eq "yourwebsite.tld"
ErrorDocument 403 https://yourwebsite.tld

<IfModule mod_rewrite.c>
 RewriteEngine On
 RewriteCond %{HTTPS} off
 RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

 RewriteBase /
 RewriteRule ^index\.php$ - [L]
 RewriteCond %{REQUEST_FILENAME} !-f
 RewriteCond %{REQUEST_FILENAME} !-d
 RewriteRule . /index.php [L]
</IfModule>

Then go through the remainder of your .htaccess and change any specific instances of your old http://yourwebsite.tld to https://yourwebsite.tld.

Open robots.txt and do the same, http changed to https.

Now’s a good time to empty your cache and check your live site to see how it’s going. Everytime I’ve done this so far it’s been all green padlock and magic S. But there’s still a couple of things to do.

Off to your Theme directory, open functions.php, and add these chunks of code:

/* content over ssl
------------------------------------------------------ */
 
function themename_ssl_content( $content ) {
 if ( is_ssl() )
 $content = str_ireplace( 'http://' . $_SERVER[ 'SERVER_NAME' ], 'https://' . $_SERVER[ 'SERVER_NAME' ], $content );
 return $content;
}

add_filter( 'the_content', 'themename_ssl_content' );

/* advanced custom fields over ssl
------------------------------------------------------ */

add_filter( 'wp_get_attachment_url', 'set_url_scheme' );

The first one makes sure your old http links in Posts and Pages are spat out as https. (Can probably extend that for excerpts and other things if you’re that way inclined.) The second was for me specifically dealing with Advanced Custom Fields plugin, and is part of a larger issue that’s been bashed around on Make WordPress Core. There’s a few other bits of code floating around for issues like this and the Media Library not behaving properly over https, but the next step I think deals with that, if you want to go that far.

Before that though, go through your theme for irksome hardcoded http strings. If you really can’t use proper WordPress functions (like get_template_directory_uri() or whatever), then change them to https.

Addendum:

Turns out WordPress’ responsive images support using src-set needs its own attention:

/* responsive images src-set
------------------------------------------------------ */

function ssl_srcset( $sources ) {
 foreach ( $sources as &$source ) {
 $source['url'] = set_url_scheme( $source['url'], 'https' );
 }

 return $sources;
}

add_filter( 'wp_calculate_image_srcset', 'ssl_srcset' );

If you fully commit to the next step though, these functions aren’t required.

(End of addendum.)

Database funtime! Backup your database, it’s time to search and replace. I’ve been using interconnect/it’s brilliant Search Replace DB for ages when I need to shift localhost websites to remote. Dump it in your WordPress folder, open it in a browser, and search-replace http://yourwebsite.tld to https://yourwebsite.tld. I do a dry run first, just to get an idea of what’s going to be changed. This step isn’t really necessary, and if you end up going back to http (dunno why), you’d need to reverse this process; it’s probably just that I like everything to be all orderly.

Another browser to make sure crap hasn’t fallen everywhere, and it’s cleanup time.

In wp-admin, check all the settings are showing https where they should (can even resave Permalinks if clicking buttons feels good). If you’re using a plugin like Yoast SEO, then checking the sitemaps are correct is good.

Caching plugins also need to be checked, and caches emptied. If you’re using W3 Total Cache and are manually minifying, check the file urls are all https, for some reason this was’t changed even with the database search replace. Also under Page Cache check “Cache SSL (https) requests”.

Then it’s checking in a couple of browsers with and without caching, particularly any pages that use plugins which embed or iframe content, or otherwise interact with stuff outside your website. Most sites like Vimeo, Twitter, YouTube etc that WordPress provides embeds for are already over https, but that doesn’t mean code in a plugin is up to date.

If you’re using Google Analytics or Webmasters or similar, you’ll need to set things up there for the new https version of your site as well.

Buncha caveats: Do some of this wrong and you will break things. At least backup your database before doing this. Some/all of this might be depreciated/incorrect/incomplete/not the best way to do it. Finding definitive, single ways to do things isn’t really how code works, so try and understand what the code does so you can ask if it’s doing what you want. For me to be able to do this in 15 minutes is because I’ve spent years scruffing around in stuff and breaking things horribly, and the best I can say is, this seems to work and cover the most common issues.

DreamHost. Let’s Encrypt. Excellent!

(I swear this is much quicker than it took to read.)