Why your all.js is empty on staging or production
When you include a non-existing Javascript file, you probably won't notice it during development. But with caching active (on production or staging) Rails will write an empty all.js file without complaining.
Related cards:
How to search through logs on staging or production environments
We generally use multiple application servers (at least two) and you have to search on all of them if you don't know which one handled the request you are looking for.
Rails application logs usually live in `/var/www//sh...
Caching in Rails < 6.1 may down parts of your application when using public cache control
Proxy caching is a good feature to serve your publicly visible application content faster and reduce load on your servers. It is e.g. available in nginx, but also affects proxies delivered by ISPs.
Unfortunately, there is a little problem in Rail...
JavaScript: Testing whether the browser is online or offline
You can use the code below to check whether the browser can make connections to the current site:
await isOnline() // resolves to true or false
Limitations of navigator.onLine
While you can use the...
Asset pipeline: Reasons why your stylesheet is empty
It might be one of the following:
- You are looking at a manifest file (like
application.css) which is always empty during development - Your Sass file has a syntax error it did not handle properly
Asset pipeline may break Javascript for IE (but only on production)
If some of your JavaScripts fail on Internet Explorer, but only in staging or production environments, chances are that JavaScript compression is the culprit.
By default, Rails 3.2 compresses JavaScript with UglifyJS. I have seen a few cases wher...
Basement.org: On The Web, More Isn’t Only Less, It’s Actually Nothing
Amidst my 400 unread Boing Boing links are probably ten or fifteen that are probably real gems. But I’ll never know and Boing Boing sure as hell isn’t going to help me out.
Decide whether cronjobs should run on one or all servers
Understanding your type of cronjob
Some cronjobs must only run on a single server. E.g. when you run nightly batch operations on the database, it should probably run on a single server. Running it on multip...
Exclude your staging site from Google with robots.txt and not shoot yourself in the foot
If you want to exclude your staging site from Google using robots.txt without running the risk to forget deleting the file once you go live, name the file robots.exclude.txt instead.
In your Apache Vhost config, rewrite requests for the stagi...
How to make Webpacker compile once for parallel tests, and only if necessary
Webpack is the future. We're using it in our latest Rails applications.
For tests, we want to compile assets like for production.
For parallel tests, we want to avoid 8 workers compiling the same files at the same time.
When assets did not change...
LoDash: isBlank and isPresent mixins
When you need to check a value for presence, don't rely on JavaScript since it considers 0 or "0" false. Also don't rely on LoDash's _.isEmpty:
if ('0') { ... } // false
if (0) { ... } // false
^
if (!_.isEmpty('0')) { ... }...