Syncthing app doesn't resolve syncthing.localhost to localhost (unlike Chrome and Firefox)

[lgarron]

While debugging #231 I found that even though I had set my URL to https://syncthing.localhost:8384 (which I have configured with a trusted certificate), Syncthing has rewritten this to http://syncthing.localhost:8384. This seems to cause the API check to fail.

I don't think it should be rewriting the URL like that.

EDIT: see #232 (comment)

[lgarron]

Hmm, looks like the code is trying to look up the scheme through

syncthing-macos/syncthing/XGSyncthing.m

Lines 179 to 185 in f063741

	if ([keyPath isEqualToString:@"configuration.gui"]) {
	if ([[[attributeDict objectForKey:@"tls"] lowercaseString] isEqualToString:@"true"]) {
	_URI = @"https://";
	} else {
	_URI = @"http://";
	}
	}

I definitely have Use HTTPS for GUI configured in the web UI, and ~/Library/Application Support/Syncthing/config.xml contains <gui enabled="true" tls="true" debugging="false" sendBasicAuthPrompt="false">

So something is going wrong with this calculation.

[xor-gate]

The code is only executed first run to load settings from the XML:

syncthing-macos/syncthing/STApplication.m

Lines 92 to 93 in f063741

	if (!_syncthing.URI.length && !_syncthing.ApiKey.length) {
	BOOL success = [_syncthing loadConfigurationFromXML];

[lgarron]

The code is only executed first run to load settings from the XML:

The API check fails due to this issue even if the app is restarted.
Did you mean to comment on #231 ?

[lgarron]

I tried debugging this in Xcode for an hour, and I still can't figure out what's causing the https:// to be dropped.

I can run the following:

defaults write com.github.xor-gate.syncthing-macosx URI -string "https://syncthing.localhost:8384"

However, this results in even more red dots in the menu, even though Syncthing is successfully running and available from the web UI:

[lgarron]

Ah, okay, I finally figured it out.

Safari (and the underlying network library) do not let localhost be localhost. This is very unintuitive if you mostly use Chrome and Firefox.

Therefore, this requires an entry in /etc/hosts to work:

127.0.0.1 syncthing.localhost

As someone who likes to namespaces localhost servers using subdomains, I guess I can live with that. This might benefit from being documented as a caveat in Syncthing docs, but I haven't found a good place for it to send a PR.

[xor-gate]

Thanks for reporting, but as you are doing non-standard things which are not supported in macOS by default. I will close this. Syncthing.app should be simple, and having this domain name for localhost service and localhost https is not the default setup. Most of the time people know then what they are doing.