Query number of players on a minecraft server

(Not an answer as it expands on Nope's, but too long for a comment, and I need code formatting)

Nope's code breaks for me (MC 1.10) as popint doesn't seem to decode multi-byte integers correctly; bytes are received in little endian order (lowest byte first). If a server has a large icon, the length doesn't get decoded correctly, which, in some cases, works anyway (as the code always reads 1024 bytes even when l is smaller), in others, you get an error from the JSON decoder about an unterminated string.

Replacing the popint function with this fixes the issue:

def popint(s):
  acc = 0
  shift=0
  b = ord(s.recv(1))
  while b & 0x80:
    acc = acc | ((b&0x7f)<<shift)
    shift = shift + 7
    b = ord(s.recv(1))
  return (acc)|(b<<shift)

Yes, there is now a quasi-official Python class to do this; it’s written by this guy.

It can be called directly from the command line (or can be used as a Python library).

To check if your server is up, get player count, etc., is as simple as:

mcstatus minecraft.example.com query

…and the exit code will be set, so you can even integrate this into e.g. automated heartbeat systems for checking uptime.

(You can use ping instead of query to test latency, at the cost of it taking a bit longer to run.)

It, unlike the currently-accepted answer:

• supports SRV-masked Minecraft servers (e.g. multiple servers on one IP)
• will stay up-to-date when Minecraft's handshake protocol next evolves
• it supports Bedrock Edition servers, too!