Embedded CI

A proof-of-concept for a CI system meant for embedded software development

This README currently functions as a journal to track my progress and ideas.

Purpose

To create a simple CI setup which will assist me when learning Embedded Rust.

The aim is to use a LattePanda 3 Delta as the CI server and connect it to a Raspberry Pi Pico and a Saleae logic analyzer.

It should be possible to:

• build embedded Rust source code
• flash it to the Raspberry Pi Pico
• use Saleae's Automation API to run tests on the Pico

Note: I initially wanted to use a Raspberry Pi 4 but Saleae's Logic does not have binaries for ARM

Current approach

I am running NixOS on the LattePanda and the following dockerized applications:

• Gitea for Git repository management
• Woodpecker as a CI engine
• MinIO for artifact storage

Use Docker Compose to run the above.

Minimal security to begin with, just to get the ball rolling.

System diagram

Steps

• Install NixOS 23.11 and use the configuration.nix file from my configfiles repository together with the embci.nix file from this repository.
• Clone this repository
• Configure the LattePanda's IP address in .env. This variable is used by docker-compose.yml. For the instructions below, replace $IP_ADDRESS with the IP address.
• Configure the debug probe serial number in .env
• Start the MinIO container docker compose up -d minio
• Access http://$IP_ADDRESS:9001/ in your browser
• Log in with minioadmin/minioadmin (the default admin user)
• Create an access key and copy the results in the MINIO_ACCESS_KEY and MINIO_SECRET_KEY variables in .env
• Start the Gitea container docker compose up -d gitea
• Access http://$IP_ADDRESS:3000/ in your browser
• Log in with embci/embci (the default admin user)
• Go to http://$IP_ADDRESS:3000/user/settings/applications and in Manage OAuth2 Applications choose:
  Application Name: Woodpecker CI
Redirect URI: http://$IP_ADDRESS:8000/authorize
  Make sure that the Confidential Client checkbox is ticked and then click Create Application
  Copy the Client ID in the WOODPECKER_GITEA_CLIENT variable in .env
  Copy the Client Secret in the WOODPECKER_GITEA_SECRET variable in .env
  Finally click Save
• Clone the https://github.com/Daedrus/embci-example-repo repository by clicking the + button in the top-right and choosing New Migration -> Github
• Create an agent secret
  openssl rand -base64 32
  and add the output to the WOODPECKER_AGENT_SECRET variable in .env
• Stop MinIO and Gitea docker compose stop
• All of the variables in .env should be set (none of them should be set to CHANGEME anymore)
• Start all containers docker compose up -d
• Access http://$IP_ADDRESS:8000/ in your browser
• Log in with embci/embci (the default admin user)
• It should ask to confirm the authentication
• Add the embci-example-repo repository to Woodpecker and run the pipeline
• Things should work out of the box provided that your hardware setup is similar to mine or, if different, you have made the necessary changes.
• Note that the Woodpecker agent is currently running in privileged mode since I couldn't get it to work with the debug probe and the analyzer otherwise. I hope to fix this in the future.