EchoHub/docs/auriondocs/Code/src/EchoHub.Client/Services/UpdateChecker.cs.md

UpdateChecker

File: src/EchoHub.Client/Services/UpdateChecker.cs
Kind: class

public sealed class UpdateChecker : IDisposable

Checks for application updates on a background schedule and coordinates a safe, post-TUI update process. Use UpdateChecker when you want automatic or on-demand update checks inside a Terminal.Gui-based host but need the actual download/extract/restart work to run after the UI main loop has exited.

Remarks

UpdateChecker encapsulates the interaction between the UI, a periodic Updater and the host process that must perform the actual update. It listens for Updater events and, when the user confirms an update via UpdateConfirmDialog.Show, sets the public PendingUpdate delegate and requests the UI to stop so the host can perform the heavy work on a plain console. This design avoids the console deadlock that would occur if the updating process tried to restart while the Terminal.Gui main loop still owned the console. CurrentVersion exposes the assembly version used in the confirmation UI.

Example

// During application startup
var checker = new UpdateChecker(app);
checker.Start(); // starts periodic checks in RELEASE builds

// Trigger a manual check from UI or command handler
await checker.CheckNowAsync();

// After the Terminal.Gui main loop exits, the host should run any pending update
if (checker.PendingUpdate != null)
{
    await checker.PendingUpdate(); // will download/extract and may restart the process
}

Notes

• PendingUpdate is only set when the user confirms an available update via UpdateConfirmDialog.Show; the host must check and invoke PendingUpdate after the TUI main loop exits.
• Start() is conditional on the RELEASE build symbol — in non-RELEASE builds the periodic checker does not run.
• Invoking the PendingUpdate delegate runs the updater on a plain console and may end by restarting the app (the code calls into the Updater which performs download/extract/restart). The host should not expect normal process continuation after the update completes.
• CurrentVersion reads the assembly version and will return "0.0.0" if the assembly version cannot be determined.
• Backup creation is attempted via UpdateBackupService.CreateBackup() before applying an update; failures are logged and the update continues without a backup.