njaldwin / canary

Canary is a simple service to monitor a few stats about Minecraft servers. Specifically, it keeps track of whether the server is down or up and how long it has been in that state as well as the MOTD and number of players.

nick aldwin

senior staff software engineer (L6) @ thrive global

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canary's Issues

Timestamp drift

In order to cope with the server and client time being off, the reference timestamp was introduced. However, due to its current implementation, there is still a slight bit of timestamp drift visible, on the order of a few seconds. This should be rectified.

Implement Full Plugin Message (Added in 1.6)

New Minecraft protocol dictates 0xFA should be followed by a channel name (list ping channel is "MC|PingHost").

Need to investigate how backwards-compatible this will be.

Support 1.4

The Server List Ping protocol changed with Minecraft 1.4. The code should be changed to connect to the new servers, but ideally still work with old servers as well.

Possible error no data when two clients ask for the same server at the same time

Due to the way locking is done, if data is malformed or nonexistent and a process is already fetching data for the server (that is, has a lock on that server), the error 'no data' is returned. Instead, perhaps it should wait for the lock to be resolved or return a 'retry' response of some kind...

JSON Changes

Breaking this out from #13. Going forward, canary should provide data in a format similar to 1.7's new JSON.

Blank Server Files Cause Issues

If a server json file is empty, it can cause an error. Blank files should be treated as if they don't exist.

Add refresh interval to json

Add the the maximum refresh interval to the json

Show server version

With the new protocol in Minecraft 1.4, servers send their version. This should be reflected in the served json at /s/server and also in the UI. This can't happen until #1 is finished.

Domains with the same IP can get back weird data

Due to #5, domains sharing the same IP use the same data file. This means, however, the hostname:port information will be from the last successful data save. Hence, the hostname:port information may fluctuate between the different domains mapping to the IP.

The information should be replaced with the requested info when possible.

Support Portless Servers

Support checking of DNS records to support portless servers as described here.

Support color formatting

Servers can return titles like §fNerdNu §2PVE\n§6Survival with no PvP §7☒ §2Rev 18. They should either be formatted with colors or, at the bare minimum, stripped out (probably on the frontend only).

http://minecraft.gamepedia.com/Formatting_codes

Add countdown

To make it clearer that Canary will auto-refresh after so many seconds, show a countdown.

Adjust interval client-side from given timestamp

Using the timestamp in the json and the interval (or maybe the server's max interval from #7), adjust the time of the next request to try and time it correctly.

Domains resolving to the same IP

Domains resolving to the same IP should not be able to circumvent TIME_BETWEEN. The data should be stored by IP when possible, and the lock should be by IP when possible.

1.7 Changes

Looks like 1.7 is going to have some changes:

* Servers can now put a 64×64 image called “server-icon.png” in their folder, that you will see on your server list.
* You can see who’s online before joining a server; move your mouse over the player count!
* Lots of hidden preparation for allowing name changes.

These might require some canary changes as well. May require #12.