Alpaca potrocol is "ip restricted"

[StefanoTesla]

Hello, as requested here Developer@AscomTalks I'm opening this enhancement request.

Currently, once Alpaca has registered a device, it tries to reconnect using the stored IP address.

But, there are many reasons why a board with a static IP may not get the expected address. Assigning static IPs outside the DHCP range is common practice, and I assumed that would always work, until I found a (poorly designed) router that would not allow a static IP outside the DHCP pool.
Based on my experience, static IP addresses should always be assigned via the router instead of the device. That being said, when the router fails to cooperate, it causes significant issues.

That led me to this idea:

Every Alpaca device should expose a UniqueID in ConfiguredDevicesResponse. I know the specification currently treats this as optional, not mandatory, but we are good developers so.... 🥹

Consider this scenario:

1. Alpaca tries to connect using the stored IP address.
2. The device cannot be reached.
3. Alpaca sends a discovery/broadcast and reads all ConfiguredDevices responses.
4. Alpaca finds the board by matching UniqueID.
5. Alpaca connects to the new IP and (optionally) stores it.

Many failure cases are still possible:

• No device responds to the broadcast.
• Devices respond, but none match the expected UniqueID.
• More than one device reports the same UniqueID.

In all of those cases, the connection would fail, which is expected.

[StefanoTesla]

added Alpaca discovery disabled in the faiulure cases

[Peter-Simpson]

Hi Stefano,

Thanks for posting your request. I've created a Platform update here: Platform with self-healing Dynamic Clients with an updated ASCOM Library that supports searching for the device by unique id if the device cannot be found at the configured IP address.

This version also has a bug fix that ensures host addresses that contain single part host names (names that have no period separators such as the name of a host PC) work as expected.

Please can you test this to see if it works with your network setup.

For those interested, the revised library (ASCOM Library 4.1.0-rc.18 ) is on our development server. To use this, add the following URL to your list of package sources: https://nuget.cloudsmith.io/ascom/rc/v3/index.json You will need to enable viewing of pre-release packages in order to see this version.

The self-healing feature is activated by supplying the device's uniqie ID in the new UniqueId field of the all parameters Alpaca Client constructor e.g. CoverCalibrator constructor or in the constructor that takes an AlpacaConfiguration object e.g. Telescope constructor.

Best wishes, Peter

[StefanoTesla]

Many thanks, I'll try it as soon as possible when I get back from vacation