wsl-ubuntu-elixir-install

Installation

Installs the prerequisites for Erlang, Elixir and Phoenix in Ubuntu on WSL including

wxWidgets
Postgres
nodejs
asdf
rust

mkdir github
cd github
git clone https://github.com/rudolfb/wsl-ubuntu-elixir-install.git
cd wsl-ubuntu-elixir-install

chmod +x *.sh

./install.sh
exit

Automating the installation of asdf and then using asdf in the same session does not seem to work, so after installing asdf, one needs to close and reopen the terminal, then continue with the installation.

cd ~/github/wsl-ubuntu-elixir-install/
./elixir-erlang-asdf-install.sh
./phoenix-install.sh

Update

./update.sh
./elixir-erlang-asdf-install.sh
./phoenix-install.sh

WSL version 2 is a lot faster than WSL version 1

wsl --set-default-version 2
wsl --list --verbose
wsl --set-version Ubuntu 2

Assigning a password for Postgres after Postgres installation

sudo service postgresql start
sudo -u postgres psql
ALTER USER postgres PASSWORD 'postgres';
\q

Then in the Elixir /config/dev.exs assign the password:

# Configure your database
config :agento, Agento.Repo,
  username: "postgres",
  password: "postgres",

Start postgresql service automatically when WSL opens

Currently, when you start WSL, services will not automatically start. Here a workaround.

First alternative

sudo visudo

Add the following to the end of the file:

%sudo ALL=(ALL) NOPASSWD: /usr/sbin/service postgresql *

Create a batch file wsl_startup.bat with the following contents:

wsl --user username --distribution Ubuntu --exec sudo service postgresql start

where username is the user you use when working in the WSL environment. The current distribution name is Ubuntu, but this may differ for other installations.

In the Windows Task Scheduler add a new task that runs this batch file when you log onto Windows.

Second alternative:

sudo nano /etc/profile.d/start-postgresql.sh

Add the following code, CTRL+O to save, and CTRL+X to exit the file.

#!/bin/bash
sudo /usr/bin/start-postgresql

Now create the above referenced file.

sudo nano /usr/bin/start-postgresql

Add the following code, CTRL+O to save, and CTRL+X to exit the file.

#!/bin/bash
if pgrep -x postgres >/dev/null
then
  echo "postgresql service already started"
else
  sudo service postgresql start
fi

Now allow the start-postgresql script to run as a script:

sudo chmod +x /usr/bin/start-postgresql

Now, when starting Ubuntu, you will always be promted once for your admin password in order to start the postgresql service. Once Ubuntu is up and runing, opeing another Ubuntu terminal window will simply report that postgresql is already running.

To avoid having to enter your password every time Ubuntu opens for the first time, execute the following.

sudo visudo

Add the following to the end of the file, CTRL+O to save, and CTRL+X to exit the file.

%sudo ALL=NOPASSWD: /usr/bin/start-postgresql
zq ALL=(ALL) NOPASSWD: ALL

VSCode

Extentions for Elixir

Extentions for CSV

Themes

https://marketplace.visualstudio.com/items?itemName=kkalita.dark-plus-elixir

The following allows one to enter snippets inside of double quotes in a template:

"editor.quickSuggestions": {
        "comments": false,
        "other": true,
        "strings": true
    }

The following will allow the html.eex and html.leex template files to be interpreted as html files in VSCode:

"emmet.includeLanguages": {
    "html-eex": "html",
    "html-leex": "html"
}

File >> Preferences >> Settings

Then search for the tag name, e.g. editor.quickSuggestions, and assign the appropriate values.

Adding project specific snippets:

File >> Preferences >> User Snippets

New snippets file for 'my_project'...

elixir.json

Paste the snippets into the JSON file. If you already have snippets in that file, you'll need to put all the snippets in one top-level JavaScript object, so remove the outer braces in the code below.

JSON doesn't allow comments, so you must remove any comment lines!

DNS

When using a VPN service such as NordVPN, the DNS of the WSL instance can be affected. A simple

sudo apt update

will fail with Temporary failure error messages.

This can be respolved easily.

Open /etc/wsl.conf and add the following to the file:

[network]
generateResolvConf = false

CTRL+O to save, and CTRL+X to exit. This will prevent WSL from overwriting the /etc/resolv.conf when restarting the WSL instance.

Unlink the /etc/resolv.conf:

sudo unlink /etc/resolv.conf

Now open the /etc/resolv.conf and assign a known DNS server

nameserver 10.33.33.1
nameserver 8.8.8.8

CTRL+O to save, and CTRL+X to exit.

The DNS ought to work immediately, and the changes ought to survive a WSL restart.

To test if the changes survive a WSL restart:

wsl --shutdown

Next restart the Ubuntu WSL and check the contents of /etc/resolv.conf

sudo nano /etc/resolv.conf

The contents ought to be the nameservers previously entered.