Geordi 4 released
4.0.0 2020-07-30
Compatible changes
- Improved documentation; README now includes command options.
- Improvement #90: geordi console, geordi deploy, geordi rake and geordi shell now work correctly if the project hasn't been bundled before
- Use binstubs if present – breaks Geordi execution when a binstub is not working
Breaking changes
- Removed deprecated executables
whenever: Installing cron jobs only for a given Rails environment or Capistrano stage
We use the whenever gem to automatically update the crontab of the servers we deploy to. By default, whenever will update all servers with a matching role (we use the :cron
role ).
This card describes how to install some tasks only for a given Rails environment or for a given Capistrano stage ("deployment target").
Installing jobs only for a given Rails environment
-----------------------------------...
Bundler in deploy mode shares gems between patch-level Ruby versions
A recent patch level Ruby update caused troubles to some of us as applications started to complain about incompatible gem versions. I'll try to explain how the faulty state most likely is achieved and how to fix it.
Theory
When you deploy a new Ruby version with capistrano-opscomplete, it will take care of a few things:
- The new Ruby version is installed
- The Bundler version stated in the Gemfil...
Fix for "Rails assets manifest file not found" in Capistrano deploy
If you use webpacker in your Rails application, and you have completely disabled Sprockets, you might get the following error when trying to deploy: Rails assets manifest file not found
. This happens inside the deploy:assets:backup_manifest
task.
This task comes from capistrano-rails. It is build for Sprockets and does not work with Webpacker out of the box.
Solution
Configure capistrano-rails to work with Webpacker
Alternative
If you are using capistrano-rails, but...
Capistrano: Finding out who deployed which revision of your application and when
Capistrano automatically logs each (successful) deployment into a file on your application servers.
It is located at the root of your server's project folder, i.e. the parent of releases
and current
, like so:
/var/www/your-project$ ls
current
log
releases
repo
revisions.log <--- here
shared
Each line in that file contains the deployed branch, commit, release ID, and username (was read from the deploying user's machine):
$ tail -n3 revisions.log
Branch master (at da45511bea63002ac2ff002d1692e09d0dd7cb88) deployed as rel...
Webpack(er): A primer
webpack is a very powerful asset bundler written in node.js to bundle (ES6) JavaScript modules, stylesheets, images, and other assets for consumption in browsers.
Webpacker is a wrapper around webpack that handles integration with Rails.
This is a short introduction.
Installation
If you haven't already, you need to install node.js and Yarn.
Then, put
gem 'webpacker', '~> 4.x' # check if 4.x is still cu...
no passenger served applications running error when deploying via capistrano
When deploying with capistrano it's possible you get this "error" message:
*** [err :: example.com] There are no Phusion Passenger-served applications running whose paths begin with '/var/www/example.com'.
*** [err :: example.com]
This is just because there were no running passenger process for this application on the server which could be restarted. It's not a real error. The application process will start if the first request for this app hits the appserver.
The output appears as err
because it's printed to stderr
.
Dep...
Migration from the Asset Pipeline to Webpacker
This is a short overview of things that are required to upgrade a project from the Asset Pipeline to Webpacker. Expect this upgrade to take a few days even the diff is quite small afterwards.
Preparations
1. Find all libraries that are bundled with the asset pipeline. You can check the application.js
and the application.css
for require
and import
statements. The source of a library is most often a gem or a vendor directory.
2. Find an working example for each library in the application and write it down.
3. Find out the ver...
During deployment: "You are trying to install in deployment mode after changing your Gemfile"
While deploying an Ruby update to an old application these days, we encountered the following misleading error:
*** [err :: some-host.makandra.de] You are trying to install in deployment mode after changing
*** [err :: some-host.makandra.de] your Gemfile. Run `bundle install` elsewhere and add the
*** [err :: some-host.makandra.de] updated Gemfile.lock to version control.
*** [err :: some-host.makandra.de]
*** [err :: some-host.makandra.de] You have deleted from the Gemfile:
*** [err :: some-host.makandra.de] *
We found out a newe...
Capistrano: Speeding up asset compile during deploy
Remember How to skip Sprockets asset compile during Capistrano deployment and Automatically skipping asset compilation when assets have not changed? Turns out there is an even better way to speed up Capistrano deployments with asset compilation – and it's even simpler.
Adding the asset cache directory to symlinked directories
Popular asset managers for Rails are Sprockets and Webpacker. Both keep a cache of already compiled files that we're going to leverage for deployments now.
- Sprockets cache...
Minify Font Awesome fonts with webpack
Font Awesome 5 is a comprehensive solution for vector icons on your website.
Originally, Font Awesome came as an icon font (plus stylesheets), but recently it can also be used as a pure JavaScript solution (which will render icons as inline <svg>
tags), or even as SVG sprites.
All solutions have their pros and cons:
Icon font:
- little CPU load (no JavaScript)
- fonts are relatively large
- 1 extra HTTP request
Javascript + inline SVG:
- higher CPU load (needs to watch the DOM via mutation observers to ad...
How to let passenger restart after deployment with capistrano
Phusion Passenger changed the way how it gets restarted several times. Through the project's history, these all were valid:
touch tmp/restart.txt
sudo passenger-config restart-app /path/to/app
passenger-config restart-app /path/to/app
You should not need to know which one to use. Instead, the capistrano-passenger gem will choose the appropriate restart mechanism automatically based on your installed the passenger version.
Installation
-
Add to your
Gemfile
:gem 'capistr...
An incomplete guide to migrate a Rails application from paperclip to carrierwave
In this example we assume that not only the storage gem changes but also the file structure on disc.
A general approach
Part A: Create a commit which includes a script that allows you to copy the existing file to the new file structure.
Part B: Create a commit which removes all paperclip logic and replace it with the same code you used in the first commit
Part A
Here are some implementation details you might want to reuse:
- Use the existing models to read the files from
- Use your own carrierwave models to write t...
Capistrano + Rails: Tagging production deploys
Just like Ruby Gems tag their version releases to the corresponding Git commit, it can be helpful to track production deploys within the commit history. This task does the tagging for you.
Capistrano 3
# lib/capistrano/tasks/deploy.rb
namespace :deploy do
...
desc 'Tag the deployed revision'
task :tag_revision do
date = Date.today.to_s
puts `git tag deploy-#{date} #{fetch :current_revision}`
puts `git push --tags origin`
end
end
# config/deploy/production.rb
after 'deploy:finished', 'deploy:tag_revi...
Capistrano + Rails: Automatically skipping asset compilation when assets have not changed
In medium-sized to large Rails applications, asset compilation can take several minutes. In order to speed up deployment, asset precompilation can be skipped. This card automates the process.
Capistrano 3
namespace :deploy do
desc 'Automatically skip asset compile if possible'
task :auto_skip_assets do
asset_locations = %r(^(Gemfile\.lock|app/assets|lib/assets|vendor/asset))
revisions = []
on roles :app do
within current_path do
revisions << capture(:cat, 'REVISION').strip
...
Capistrano task to tail remote application logs of multiple servers
When your application is running on a multi-server setup, application logs are stored per server (unless you choose a centralized logging solution).
Here is a Capistrano task that connects to all servers and prints logs to your terminal like this:
$ cap production app:logs
00:00 app:logs
01 tail -n0 -F /var/www/your-application/shared/log/production.log | while read line; do echo "$(hostname): $line"; done
01 app01-prod: Started GET "/sign_in" for 1.2.3.4 at 2018-04-26 11:28:19 +0200
01 app01-prod: Proc...
How to make Capistrano not truncate server output
By default, Capistrano truncates server responses and places an ellipsis at the end of lines that are longer than your terminal. Error messages are never truncated.
While this can be helpful to make deployment output appear less noisy, it also hides information that could be helpful.
I believe you should prefer knowing what is going on, even if causes a few extra lines of output.
Capistrano by default uses Airbrussh which is where truncation happens. To disable truncation globally, place this into your deploy.rb
:
set :format_options...
How to skip Sprockets asset compile during Capistrano deployment
For applications coming with lots of stylesheets and scripts, asset compilation might take quite long. This can be annoying when deploying a release that does not actually change assets.
When your app uses Sprockets, you can simply skip asset compilation and re-use the previous release's assets. [1]
That is especially easy via Capistrano. Capistrano will automatically symlink your release's public/assets
to a shared directory, so all you need to do is skip the deploy:assets:precompile
task.
Put the following code where you'd put other ...
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 multiple servers would likely result in deadlocks or corrupt data.
Some cronjobs must always run on all servers. E.g. starting a sidekiq process on reboot.
Configuring whenever
If not configured otherwise, cronjobs defined in whenever's `s...
Capistrano: Doing things on rollback
Capistrano has the concept of a "rollback" that comes in really handy in case of errors. When you notice that your recent deploy was faulty, run cap deploy:rollback
and you're back with the previous release. In case of an error during a deployment, Capistrano will rollback itself.
But, you may ask, how can it know how to revert all the custom stuff I'm doing during deployment? It can't. But you can tell it how to.
Capistrano 3
Deploy and rollback are nearly identi...
Capistrano 2: How to deploy a single server
When you have a multi-server setup, you'll be adding a new server from time to time. Before doing a full deploy, you might want to test that server in an isolated deploy. There is a single way to do this: the HOSTFILTER
env variable.
Commenting out "server" lines in the Capistrano deploy config will raise a Capistrano::NoMatchingServersError
with <task> is only run for servers matching {:roles=> <role>}, but no servers matched
. Instead, specify the server-under-test like this:
HOSTFILTER=separate-sidekiq.makandra.de cap productio...
Middleman: Use pretty URLs without doubling requests
By default Middleman generates files with a .html
extension. Because of this all your URLs end in /foo.html
instead of /foo
, which looks a bit old school.
To get prettier URLs, Middleman lets you activate :directory_indexes
in config.rb
. This makes a directory for each of your pages and puts a single file index.html
into it, e.g. /foo/index.html
. This lets you access pages with http://domain/foo
.
Don't double your requests!
Unfortunately you are now forcing every br...
Middleman configuration for Rails Developers
Middleman is a static page generator that brings many of the goodies that Rails developers are used to.
Out of the box, Middleman brings Haml, Sass, helpers etc. However, it can be configured to do even better. This card is a list of improvement hints for a Rails developer.
Gemfile
Remove tzinfo-data
and wdm
unless you're on Windows. Add these gems:
gem 'middleman-livereload'
gem 'middleman-sprockets' # Asset pipeline!
gem 'bootstrap-sass' # If you want to use Bootstrap
gem 'byebug'
gem 'capistrano'
gem 'capistrano-mid...
Capistrano 3: How to deploy when a firewall blocks your git repo
Sometimes, through some firewall or proxy misconfiguration, you might have to deploy to a server that cannot access the git repository.
Solution 1: HTTP Proxy (this is the preferred fix)
SSH can be tunneled over an HTTP Proxy. For example, when the repo is on github
, use this:
-
Install
socat
-
Add a
~/.ssh/config
on the target server(s) with permission 0600 and this content:Host github.com ssh.github.com User git Hostname ssh.github.com Port 443 ProxyCommand socat - PROXY:<your proxyhost>:%h:%p,...