I've been on the fence about Phoenix and Elixir for a while and I thought I'd take at least a quick dive. I've had a development system for Phoenix and Elixir since at least 2016 but I haven't done much. This means that the first task is bringing it into the 2020s.
I installed Elixir via HomeBrew which means it is a simple:
which elixir /usr/local/bin/elixir
Note: It can be hard sometimes to know if you installed things via HomeBrew and checking their location is an easy cheap as HomeBrew installs stuff to /usr/local/bin
brew upgrade elixir
elixir --version Erlang/OTP 23 [erts-11.0.3] [source] [64-bit] [smp:16:16] [ds:16:16:10] [async-threads:1] [hipe] [dtrace] Elixir 1.10.4 (compiled with Erlang/OTP 23)
You can also use just -v:
elixir -v Erlang/OTP 23 [erts-11.0.3] [source] [64-bit] [smp:16:16] [ds:16:16:10] [async-threads:1] [hipe] [dtrace] Elixir 1.10.4 (compiled with Erlang/OTP 23)
Upgrading Mix and Hex
Mix and Hex give the equivalent of a build tool (like Rake from the Rails world) and a Package Manager (like Gem / Bundler).
To upgrade mix, you use:
mix local.hex Found existing entry: /Users/sjohnson/.mix/archives/hex-0.20.5 Are you sure you want to replace it with "https://repo.hex.pm/installs/1.10.0/hex-0.20.5.ez"? [Yn] Y * creating /Users/sjohnson/.mix/archives/hex-0.20.5
And that will upgrade both mix and hex.
The phoenix framework version I have dates back to 1.2 or 1.3 I think. The first step is to figure out what version I have:
mix phoenix.new --version Phoenix v1.3.3
The method to upgrade the Phoenix framework itself is:
mix archive.install hex phx_new 1.5.4
I used a google query to discover that the current Phoenix framework version was 1.5.4. The other way to find this version number is to go to this url:
And then look at the drop down of different versions in the left hand sidebar. The latest version is always at the top.
Creating a Sample App
My first step was to create a location to work on Phoenix apps. I'm going to be experimenting with a version of my JobHound app written in Phoenix so I created this directory:
mkdir -p /Users/sjohnson/Sync/coding/jobhound/phoenix
I can then move my existing Rails source code into:
and be able to open both code bases in the same editor window which should facilitate copy and paste based code rewriting.
With all the tooling updated, creating a new Phoenix app is as a simple matter of:
cd /Users/sjohnson/Sync/coding/jobhound/phoenix mix phx.new jobhound
You should see a bunch of output looking like this:
* creating jobhound/config/config.exs * creating jobhound/config/dev.exs * creating jobhound/config/prod.exs * creating jobhound/config/prod.secret.exs * creating jobhound/config/test.exs * creating jobhound/lib/jobhound/application.ex * creating jobhound/lib/jobhound.ex * creating jobhound/lib/jobhound_web/channels/user_socket.ex * creating jobhound/lib/jobhound_web/views/error_helpers.ex * creating jobhound/lib/jobhound_web/views/error_view.ex * creating jobhound/lib/jobhound_web/endpoint.ex * creating jobhound/lib/jobhound_web/router.ex * creating jobhound/lib/jobhound_web/telemetry.ex
This created the canonical structure for a Phoenix app: