Fix checking for gui updates

[mmbyday]

#2089

[sanderfoobar]

function onWalletCheckUpdatesComplete(update) {

update is always empty for me. This is the bug I meant in #2089

[erciccione]

I'm not sure the direct link is the best option.Maybe would be better something more mininmalistic? like: "a new version is available, check out getmonero.org".

[sanderfoobar]

To verify, how were you able to test the update mechanism? Can you confirm the GUI:

1. Makes a DNS request on startup
2. WalletManager::checkUpdatesAsync emits the checkUpdatesComplete with a non-empty update parameter when it is done checking.
3. So that onWalletCheckUpdatesComplete(update) in main.qml is not empty
4. So that it shows the dialog

^ cannot reproduce

[mmbyday]

@xmrdsc Good questions. I tested this PR against the v0.13.0.4 branch, as you may see from clues in the GUI (missing accounts, openalias placeholdertext)

Yes, your understanding sounds almost right. In step 2, checkUpdatesComplete can be empty when there is no update.

You can look under the hood of WalletManager::checkUpdates and see that the tuple of update data comes from Monero::WalletManager::checkUpdates here:
https://github.com/monero-project/monero/blob/29073f65e8816d4c32b6ffef514943a5650b8d3b/src/wallet/api/wallet_manager.cpp#L334

When there is no new update, this is why update parameter is empty.

return std::make_tuple(false, "", "", "", "");

Hope that helps you.

[mmbyday]

@erciccione That's a good option. It's simple and minimalistic as you say. Ultimately however, I think the typical user wants a one-click update though. That's what most user friendly wallets do for updates, like ledger-live. That would be a separate PR however. This one is just to get it working again :-)

[mmbyday]

Rebased.

[xiphon]

Return or throw a error in the unknown/unrecognized OS case.

[mmbyday]

Excellent idea. Thanks.

[mmbyday]

Updated to handle unknown/unrecognized OS case with generic message.