ftb-snbt-lib

A python library to parse, edit, and save FTB snbt tag.

The FTB snbt tag is a variant of the "vanilla" snbt tag. It has no commas at end of lines, different suffixes for numeric values, and no support for array data type.

This is the example of the FTB snbt tag:

{
    some_tag: "some_value"
    another_tag: 1b
    list_tag: [
        "a"
        "b"
        "c"
    ]
}

This library is only for the FTB snbt tag. If you are finding the snbt library for the "vanilla" snbt tag, use nbtlib by vberlier.

Installation

The package can be installed with pip.

$ pip install ftb-snbt-lib

Getting Started

• Import the library.

>>> import ftb_snbt_lib as slib

• load(fp): Load the ftb snbt tag from a file (fp).

>>> some_snbt = slib.load(open("tests/some_file.snbt", "r", encoding="utf-8"))

• The type of returned value is Compound, a dictionary-like object.
  The Compound is containing values with tag data types provided by this library.

>>> type(some_snbt)
<class 'ftb_snbt_lib.tag.Compound'>
>>> print(some_snbt)
Compound({'some_tag': String('some_value'), 'another_tag': Byte(1)})

• dump(tag, fp): Dump the ftb snbt tag to a file (fp).

>>> slib.dump(some_snbt, open("tests/some_file_copy.snbt", "w", encoding="utf-8"))

• loads(s): Load the ftb snbt tag from a string s.

>>> another_snbt = slib.loads('''
... {
...     some_tag: "some_value"
...     another_tag: 1b
... }
... ''')

• dumps(tag): Dump the ftb snbt tag to a string.

>>> dumped_snbt = slib.dumps(another_snbt)
>>> print(dumped_snbt)
{
    some_tag: "some_value"
    another_tag: 1b
}

• Edit the snbt tag. As its type is Compound, it can be edited like a dictionary.
  The inserted or replace values should be any of tag data types provided by this library.

>>> another_snbt["some_tag"] = slib.String("another_value")

• When editing the List, a list-like object, its elements must have the same type.
  For instance, List[Byte(1), Byte(2), Byte(3)] must contain only the Byte type object, so the other types like Integer or String cannot be added or replaced in it.

• When editing the Array, a list-like object with a fixed length, its elements must have the same type, and that type must match the element type defined in the array.
  For instance, IntArray with a length of 3 must contain three Integer type objects, so adding new objects, removing existing objects, and replacing with other type objects are not allowed.

• Save the edited snbt tag to a json file.

>>> import json
>>> json.dump(another_snbt, open("tests/test.json", "w", encoding="utf-8"), indent=4, ensure_ascii=False)

Data Types

Type	Description	Format	Example
Byte	A signed 8-bit integer. Range: -128 ~ 127	<number>b	12b, -35b
Short	A signed 16-bit integer. Range: -32,768 ~ 32,767	<number>s	132s, -243s
Integer	A signed 32-bit integer. Range: -2,147,483,647 ~ 2,147,483,647	<number>	12345
Long	A signed 64-bit integer. Range: 9,223,372,036,854,775,808 ~ 9,223,372,036,854,775,807	<number>L	12345L
Float	A 32-bit, single-precision floating-point number. Range: -3.4E+38 ~ +3.4E+38	<number>f	12.345f, 1.0E-6f
Double	A 64-bit, double-precision floating-point number. Range: -1.7E+308 ~ +1.7E+308	<number>d	12.345d, 1.0E-6d
Bool	A boolean data type. 0 for false, 1 for true.	false, true	true
String	A sequence of characters.	A string enclosed in double quotes "". Nested double quotes can be included within a string using a escaping character \".	"Hello, World!", "Say \"Hello, World!\""
List	An ordered list of tags. The tags must be of the same type, determined by the first tag in the list.	Unnamed tags enclosed in square brackets and delimited by newline characters (\n).	[ 3.2d 1.4d ... ]
Array	An ordered list of 8-bit(ByteArray), 32-bit(IntArray), 64-bit(LongArray) integers.	<array_prefix>; followed by an ordered list of tags enclosed in square brackets and delimited by newline characters (\n). Valid array prefixes are B(Byte), I(Integer), and L(Long).	[B; 12b -35b ... ]
Compound	An ordered list of attribute-value pairs. Each tag can be of any type.	Named tags enclosed in curly braces and delimited by commas or newline characters (\n). The key (tag name) can be unquoted if it contains only 0-9, A-Z, a-z, _, -, ., and +. Otherwise the key should be quoted, using the format of String type.	[ tag1: "string" tag2: 12b "quoted:tag": 3.5d ... ]

References

• PLY - Python Lex-Yacc by David Beazley
• nbtlib by vberlier
• NBT format - Minecraft Wiki (fandom)