mod-app-ddns: Absent Interface: "wan" shown by default for the Interface IP address source

[adelton]

Is there an existing issue for this?

• I have searched among all existing issues (including closed issues)

screenshots or captures

Actual behaviour

1. When IP address source is changed to Interface, the Interface popup list has default selection of Absent Interface: "wan"

Expected behaviour

1. The default selection should likely be the Alias Interface: "@wan"

Steps to reproduce

1. In System > Software click Update lists ...
2. In Filter type luci-app-ddns
3. In the Available tab see the line with luci-app-ddns, click Install ...
4. Reload the page (for example with Ctrl+R)
5. A new Services top level menu item should appear between System and Network
6. In Services > Dynamic DNS click Add new services ...
7. Put in Name test, click Create service
8. Select the Advanced Settings tab
9. Change the IP address source from Network to Interface
10. Check the Interface selection and default value.

Additional Information

{
	"kernel": "6.6.69",
	"hostname": "OpenWrt",
	"system": "Intel(R) Core(TM) i7-10610U CPU @ 1.80GHz",
	"model": "QEMU Standard PC (Q35 + ICH9, 2009)",
	"board_name": "qemu-standard-pc-q35-ich9-2009",
	"rootfs_type": "squashfs",
	"release": {
		"distribution": "OpenWrt",
		"version": "24.10.0-rc5",
		"revision": "r28304-6dacba30a7",
		"target": "x86/64",
		"description": "OpenWrt 24.10.0-rc5 r28304-6dacba30a7",
		"builddate": "1736026537"
	}
}

What browsers do you see the problem on?

Firefox

Relevant log output

No response

[adelton]

I got to look at the behaviour of those selections while looking at the possibility of addressing #4229. Getting the defaults changes might not be as easy as I initially thought, so I'm filing this specific weirdness to be possible address independently from the IPv4 / IPv6 changes.

[systemcrash]

I believe wan is the default since it exists on most devices by default, and @alias interfaces require (or previously have required) extra lookups to determine the L3/L2 device it refers to. I think the ddns-scripts take this into account.

[systemcrash]

You might want to check which exists, in some descending preference order, or just skip wan entirely and mandate that the user choose an interface.

[systemcrash]

(in any case, wan exists on my system).

[adelton]

@systemcrash What would be the right idiomatic way of checking for an existence of an interface in code?

[adelton]

Ah, got a reasonably working code with network.getDevice('wan'), shown in #7555 now.