“...I've been working since 2008 with Ruby / Ruby on Rails, love a bit of Elixir / Phoenix and learning Rust.
I also poke through other people's code and make PRs for OpenSource Ruby projects that sometimes make it. Currently working for InPay who are based in Denmark...”
I still haven’t got to grips with Docker, I need to sort out our CI environment as it’s a bit weird and stuff is missing so….let’s give Docker a whirl. I’ve already got it installed so.
Robs-MacBook-Pro:rostering rl$ docker version
Client: Docker Engine - Community
Version: 19.03.12
API version: 1.40
Go version: go1.13.10
Git commit: 48a66213fe
Built: Mon Jun 22 15:41:33 2020
OS/Arch: darwin/amd64
Experimental: false
Server: Docker Engine - Community
Engine:
Version: 19.03.12
API version: 1.40 (minimum version 1.12)
Go version: go1.13.10
Git commit: 48a66213fe
Built: Mon Jun 22 15:49:27 2020
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: v1.2.13
GitCommit: 7ad184331fa3e55e52b890ea95e65ba581ae3429
runc:
Version: 1.0.0-rc10
GitCommit: dc9208a3303feef5b3839f4323d9beb36df0a9dd
docker-init:
Version: 0.18.0
GitCommit: fec3683
Run a Ruby command without that version of Ruby installed.
Robs-MacBook-Pro:rostering rl$ docker run ruby:2.7 ruby -e "puts :hello"
hello
Ok that’s pretty cool :)
Now if we want to mount an existing directory inside our Docker instance, and boot it with interactive mode
Robs-MacBook-Pro:rostering rl$ docker run -it -v ${PWD}:/apps/rostering ruby:2.6.6 bash
Unable to find image 'ruby:2.6.6' locally
2.6.6: Pulling from library/ruby
d6ff36c9ec48: Already exists
root@520c19cb27a6:/# cd apps/rostering/
root@520c19cb27a6:/apps/rostering# bundle install
Traceback (most recent call last):
2: from /usr/local/bin/bundle:23:in `<main>'
1: from /usr/local/lib/ruby/2.6.0/rubygems.rb:302:in `activate_bin_path'
/usr/local/lib/ruby/2.6.0/rubygems.rb:283:in `find_spec_for_exe': Could not find 'bundler' (2.1.4) required by your /apps/rostering/Gemfile.lock. (Gem::GemNotFoundException)
To update to the latest version installed on your system, run `bundle update --bundler`.
To install the missing version, run `gem install bundler:2.1.4`
root@520c19cb27a6:/apps/rostering# gem install bundler:2.1.4
Fetching bundler-2.1.4.gem
Successfully installed bundler-2.1.4
1 gem installed
It’s effectively a new version of Ruby with no dependencies, so we need to install bundler, etc.
2. It’s not quite Erlang either, Elixir is different
3. Assignment is not assignment, it’s making sure stuff matches
iex(18)> a = 1
1
iex(19)> 1 = a
1
iex(20)> 2 = a
** (MatchError) no match of right hand side value: 1
(stdlib) erl_eval.erl:453: :erl_eval.expr/5
(iex) lib/iex/evaluator.ex:257: IEx.Evaluator.handle_eval/5
(iex) lib/iex/evaluator.ex:237: IEx.Evaluator.do_eval/3
(iex) lib/iex/evaluator.ex:215: IEx.Evaluator.eval/3
(iex) lib/iex/evaluator.ex:103: IEx.Evaluator.loop/1
(iex) lib/iex/evaluator.ex:27: IEx.Evaluator.init/4
iex(20)> a = 2
2
iex(21)> 2 = a
If you’ve never heard of why the lucky stiff perhaps you’ve been living under a rock for the past 10 years and hitting your Ruby apps with a blunt tuna. They wrote a ton of stuff in Ruby such as Hpricot, Shoes, Syck, Camping, I could go on I won’t.
_why also wrote an online book called why’s (poignant) guide to ruby, it’s inspirational and funny and bat shit silly. You should read it. I managed to get a physical copy because someone decided to put lots of effort into making it so.
If you ever find this, buy it, read it, code till your fingers are a bit sore.