Edge daemon for running on edge nodes deployed by jtcressy-home

stateDiagram-v2
    [*] --> EdgeDaemon
    state EdgeDaemon {
        [*] --> TailscaleController
        state TailscaleController {
            [*] --> NoState
            NoState --> NeedsLogin
            NeedsLogin --> Running: QRCodeScanned
            Running --> NeedsLogin: Logout
            NoState --> Running: Connect
            Running --> Stopped: Disconnect
            Stopped --> Running: Connect
        }
        --
        [*] --> ProvisioningController
        state ProvisioningController {
            [*] --> WaitingForConfig
            WaitingForConfig --> WaitingForConfig: FetchMachineIDToken
            WaitingForConfig --> Configuring: TagsAssigned
            Configuring --> Configuring: FetchMachineConfig
            Configuring --> Configured: ConfigDone
            Configured --> Configured: NoChanges
            Configured --> WaitingForConfig: ConfigChanged
        }
        --
        [*] --> DisplayController
        state DisplayController {
            [*] --> b: IfTailscaleNeedsAuth
            [*] --> r: IfTailscaleRunning
            state "DisplayBootstrap" as b
            state "DisplayRunning" as r
        }
    }

The TailscaleController will be responsible for managing the Tailscale daemon connection state, such as assisting with bootstrapping by triggering the interactive login flow to maintain a fresh authentication URL until an operator bootstraps the machine with Tailscale control/admin panel.

The ProvisioningController will be responsible for configuring the device based on the devices tags from the Tailscale admin panel. The tags basically act as roles for the device to assume, such as k8s master, k8s worker and so on. It is not yet determined what tools will be used to complete configuration or bootstrap kubernetes. This is a work-in-progress.

The DisplayController is responsible for managing various display methods for reporting the status of the Tailscale and Provisioning controllers. It is intended to control a handful of physical displays depending on device type.

Currently, it is in the roadmap to support the following display types:

• TUI via tty0 (replaces standard getty login prompt on linux)
• SSD1306 OLED display via i2c
• HD44780 LCD display via i2c (either 16x2 or 20x4)

The Auth URL exposed by Tailscale will be displayed as a QR code when possible, or standard shortened text URL otherwise.