WSL + Docker without Desktop — Communicate with Windows Host

Preface

This post present a solution to stop using Docker Desktop and use only Docker Engine on WSL.

I decide to use :

WSL2
Ubuntu 20.04
Docker Engine for Linux
Docker Compose for Linux

I want to do something like this :

Prerequisite

Install WSL version 2 (see Microsoft documentation)
Install Linux (personally I choose Ubuntu)
Clone this repository
Have the rights to modify the configuration of the Windows firewall

Configure WSL

You maybe need to configure WSL to limit processor and memory usage.

This can be done with the file .wslconfig in your Windows profile folder (%USERPROFILE%).

[wsl2]
memory=4GB # Limits VM memory in WSL 2 up to 4GB
processors=2 # Makes the WSL 2 VM use two virtual processors

See Microsoft documentation.

Install Docker

From Docker documentation :

WSL TERMINAL :
sudo apt-get update
sudo apt-get install apt-transport-https ca-certificates curl gnupg lsb-release
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
echo \
  "deb [arch=amd64 signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu \
  $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
sudo apt-get install docker-ce docker-ce-cli containerd.io
sudo docker run hello-world

You will have an error here :

Docker service didn’t start automatically in WSL, even if you reboot Ubuntu, since systemd is not enabled.

WSL TERMINAL :
service --status-all

You can start it manually :

WSL TERMINAL :
sudo service docker start

Allow Docker without sudo (see Docker post installation documentation)

WSL TERMINAL :
sudo groupadd docker
sudo usermod -aG docker $USER
newgrp docker
docker run hello-world

Install Docker Compose

WSL TERMINAL :
sudo apt update
sudo apt install docker-compose

Start multi-container with Docker Compose

Let’s try to start a Kafka environment with Docker Compose, my docker-compose.yml file can be found in the src folder.

WSL TERMINAL :
docker-compose up -d

WSL TERMINAL :
docker-compose ps

Ok, we have a Kafka environment in WSL, now let’s try to send a message.

WSL TERMINAL :
curl http://localhost:8082/topics -w "\n"

WINDOWS POWERSHELL :
Invoke-WebRequest -Uri 'http://[::1]:8082/topics/hello-topic' -Method POST -ContentType 'application/vnd.kafka.json.v2+json' -Body '{"records":[{"value":{"Message": "Hello Kafka!"}}]}' -UseBasicParsing

WSL TERMINAL :
curl http://localhost:8082/topics -w "\n"

To communicate with the container, you must use this address [::1].

Communicate with Windows from the containers

Ok, now let’s try to communicate with Windows host. You can read the Microsoft documentation.

First, we have to find his IP address :

WSL TERMINAL :
cat /etc/resolv.conf

Secondly, we have to configure the firewall to authorize communication :

WINDOWS POWERSHELL :
# Run as Administrator
New-NetFirewallRule -DisplayName "WSL" -Direction Inbound -InterfaceAlias "vEthernet (WSL)" -Action Allow

Finally, we start Kafka environnement with a listener application.

Note : you have to fix the IP address in the file docker-compose.listener.yml :

ListenerConfig__Host: http://172.17.80.1:5002

Now start Kafka and the listener :

WSL TERMINAL :
docker-compose -f docker-compose.yml -f docker-compose.listener.yml up -d --build && docker attach listener

Then, let’s start an application on the host to handle HTTP message :

WINDOWS POWERSHELL :
# Use the WSL IP address
dotnet run --urls "http://172.17.80.1:5002"

Send a message to Kafka :

WINDOWS POWERSHELL :
Invoke-WebRequest -Uri 'http://[::1]:8082/topics/hello-topic' -Method POST -ContentType 'application/vnd.kafka.json.v2+json' -Body '{"records":[{"value":{"Message": "Hello Kafka!"}}]}' -UseBasicParsing

You should see this message in both applications :