Added alerts when cannot access the server or the mhub-server

[ThinkRedstone]

If the server is shutdown or you do not have network interfaces online, the alert is almost instantaneous; however if you do have access to the internet, the alert will only pop up after a a fairly long while- this is because it takes a while for your browser to verify there is no server listening on that particular address. You can use jQuery.ajaxSetup to set a custom timeout, and catch "timeout" as well as "error" to circumvent that. A similar idea could probably used with the mhub alerts, if we can decide on a timeout.

[rikkertkoppes]

I would vote for some more helpful message. After all, we are talking to an end user. Remove the exclamation marks, add something like "cannot connect to xxx, check whether your network connection is available and the the xxx service is running"

@kmeesters may have some politically correct wordings (although that may end up lengthy)

Otherwise, a very useful addition

[kmeesters]

Sorry didn't see this mention. As suggestion:
"Could not connect to MHub server. Please check your network connection and/or the server status"
However we might also need to fix the 'enable messaging button'. After all people can also use the scoring without MHub.

[alanggreen]

Don't you think that mentioning MHub server is going to be difficult for most users? Will a referee entering scores on a tablet understand a message like that?

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On Fri, Sep 22, 2017 at 12:00 AM, Kenny meesters ***@***.***> wrote: Sorry didn't see this mention. As suggestion: "Could not connect to MHub server. Please check your network connection and/or the server status" However we might also need to fix the 'enable messaging button'. After all people can also use the scoring without MHub. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#265 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AGccjZdZ9fV0qX61bxUIQ8jllYLVNMtQks5sks6HgaJpZM4PBt1g> .

[kmeesters]

well, yes, but in case of the referee. MHub being reachable and the connection are not the same. The referee does not use MHub but rather the internal server (api/rest) of the scoring system.

I assume that this commit (as the title indicates) is really to check MHub, which is really for the scorekeeper, as the 'server' will connect to MHub, but it is mainly operated through the admin (scorekeeper) interface. This is different from a general 'connection loss' error (which would be relevant for the referee), @poelstra is working on that with the syncing commit.

Finally, a descriptive error message will help people better understand what is going on. More specifically the people who provide tech support during the event. Of course we can also (or rather) should include help files with more details. I agree we could think about a more generic therm for 'Mhub' (like: message server' or 'tournament server'), but I would avoid something generic like 'connection loss', that just raises more questions.

Also, keep in mind that we need to fix the 'enable messaging' setting for this as well (as we discussed on Slack)