Minecraft command parser

Command parser and reconstructor for minecraft commands in pure python (requires python3.7+).

This project currently supports minecraft 1.8 - 1.16

Installing

mcfunction.py is currently not on PyPi, but you can use the commad below

pip install git+https://[email protected]/Le0Developer/mcfunction.py.git

If you need a specific version, use @

pip install git+https://[email protected]/Le0Developer/[email protected]

Parsing & Reconstructing

You can use the parse_command function to parse a command.

from mcfunction import parse_command
from mcfunction.versions.mc_1_8.summon import ParsedSummonCommand

command = parse_command('summon minecraft:ender_dragon ~ ~ ~')
# command is the parsed command
command: ParsedSummonCommand  # for type-hinting

# you can use 'str(command)' to construct the command from the parsed command
print(command)  # print() automatically calls str()
print(repr(command))  # bypasses str() and lets you see the real 'command'

# modify the node of the summoned entity
command.entity.name = 'wither'

# reconstruction will show the changed command
print(command)

Creating ParsedCommand manually

You can create the ParsedCommand directly if you don't have a string for parse_command.

from mcfunction import nodes
from mcfunction.versions.mc_1_8.summon import ParsedSummonCommand
# versions.mc_1_8 because the summon command were using was last changed in 1.8

command = ParsedSummonCommand(
    'summon',  # first argument is always the command name  (for alias support)
    nodes.NamespaceIDNode('minecraft', 'elder_guardian'),
    nodes.PositionNode(
        nodes.CoordinateNode(0, relative=True),
        nodes.CoordinateNode(0, relative=True),
        nodes.CoordinateNode(0, relative=True)
    )
)

print(command)

Creating your own commands

It's actually really simple. Let's assume you have a greet command and its syntax is greet <target> [message].

Greet Command

from dataclasses import dataclass

from mcfunction.versions import Command, ParsedCommand, Parser
from mcfunction.nodes import EntityNode, RawNode
from mcfunction.parser_types import Entity, GreedyAny


# you don't need to use dataclasses, you can create the __init__ yourself
@dataclass()
class ParsedGreetCommand(ParsedCommand):
    command: str

    target: EntityNode  # the target of your command

    reason: RawNode = None  # raw text, but it's optional, so ' = None'

    # this is the construction function, this should return the command as
    #   string
    def __str__(self):
        if self.reason is not None:
            # EntityNode and RawNode have a __str__ too, so you can just use
            # them in f-strings like this
            return f'{self.command} {self.target} {self.reason}'
        return f'{self.command} {self.target}'


# now you can create your command
greet = Command('greet', parsed=ParsedGreetCommand)

# add your syntax
greet.add_variation(
    # parses a 'Entity' and puts the parsed node into the 'target' field
    Parser(Entity(), 'target'),
    # 'GreedyAny' parses all the remaining arguments into a single node
    Parser(GreedyAny(), 'reason')
)
# and add the variation without reason
greet.add_variation(
    Parser(Entity(), 'target')
)


# you can use `greet.parse` to parse a command now
parsed = greet.parse('greet @a Hello World')

# or add it to a version to make it work everywhere
from mcfunction import get_version, parse_command
version = get_version()  # latest version
version.add_command(greet)

parsed = parse_command('greet @a Hello World')

Parsing & Reconstruction of .mcfunction files

You can use the parse_mcfunction function to parse a mcfunction file.

You could parse each line with parse_command, but you'd need to ignore comments and blank lines (so it doesn't crash). parse_mcfunction handles blank lines and comments for you.

from mcfunction import parse_mcfunction
from mcfunction.mcfunction import NoCommand

commands = [
    '# summon enderdragon'
    'summon minecraft:ender_dragon ~ ~ ~',
    '',
    '#summon wither',  # both comment styles supported
    'summon minecraft:wither ~ ~ ~',
]
mcfunction = parse_mcfunction(commands)

# get the summon commands by simply accessing the list
summon_enderdragon = mcfunction.commands[1]
summon_wither = mcfunction.commands[4]

for command in mcfunction.commands:
    # only print commands, not blank lines or comments
    if not isinstance(command, NoCommand):
        print('command', command)

# you can access the comment
print(mcfunction.commands[0].comment.value)
# change it;
mcfunction.commands[0].comment.value = 'summon sheep'
summon_enderdragon.entity.name = 'sheep'
# you can also change the style
mcfunction.commands[2].command = '# '

Versions

This library currently supports 1.8 - 1.16.

When using a parse function (parse_command and parse_mcfunction) you can specfiy which version's syntax you want (defaults to the latest version).

from mcfunction import parse_command, get_version
from mcfunction.versions.mc_1_8.execute import ParsedExecuteCommand

version = get_version('1.8')  # 1.8, 1.9, 1.10, ...

# execute was reworked in 1.13 with totally new syntax, but
# we can use the old 1.8 syntax with this
command = parse_command('execute @p ~ ~ ~ say 1.8 > all', version)
command: ParsedExecuteCommand  # for type hinting

NOTE: Note for type-hinting. If you're using e.g. 1.16 and a command which wasn't changed since 1.8, you have to use 1.8 as version when importing. mcfunction.versions.mc_1_8.ban instead of mcfunction.versions.mc_1_16.ban

Dependencies

This project does not use any external dependencies, except for development/testing.

• pytest

  • pytest is used for testing the program, install it with pip install pytest
  • make test for testing

• flake8

  • flake8 is used for linting the program, install it with pip install flake8
  • make lint for linting

• coverage

  • coverage is used for generating test coverage, install it with pip install coverage
  • make coverage for generating the test coverage (requires pytest)