
# PyNBT
PyNBT is a tiny, liberally licenced (MIT) NBT library.
It supports reading and writing big endian or little endian NBT files.
Tested and supported on Py3.5-Py3.9, pypy3.
## Using the Library
Using the library in your own programs is simple and is capable of reading, modifying, and saving NBT files.
### Writing
**NOTE**: Beginning with version 1.1.0, names are optional for TAG_*'s that are added to a TAG_Compound, as they will be given the same name as their key. If you do
specify a name, it will be used instead. This breaks compatibility with old code, as the position of the `name` and `value` parameter have now swapped.
```python
from pynbt import NBTFile, TAG_Long, TAG_List, TAG_String
value = {
'long_test': TAG_Long(104005),
'list_test': TAG_List(TAG_String, [
'Timmy',
'Billy',
'Sally'
])
}
nbt = NBTFile(value=value)
with open('out.nbt', 'wb') as io:
nbt.save(io)
```
### Reading
Reading is simple, and will accept any file-like object providing `read()`.
Simply pretty-printing the file created from the example under writing:
```python
from pynbt import NBTFile
with open('out.nbt', 'rb') as io:
nbt = NBTFile(io)
print(nbt.pretty())
```
This produces the output:
```
TAG_Compound(''): 2 entries
{
TAG_Long('long_test'): 104005
TAG_List('list_test'): 3 entries
{
TAG_String(None): 'Timmy'
TAG_String(None): 'Billy'
TAG_String(None): 'Sally'
}
}
```
Every tag exposes a minimum of two fields, `.name` and `.value`. Every tag's value maps to a plain Python type, such as a `dict()` for `TAG_Compound` and a `list()` for `TAG_List`. Every tag
also provides complete `__repr__` methods for printing. This makes traversal very simple and familiar to existing Python developers.
```python
with open('out.nbt', 'rb') as io:
nbt = NBTFile(io)
# Iterate over every TAG in the root compound as you would any other dict
for name, tag in nbt.items():
print(name, tag)
# Print every tag in a list
for tag in nbt['list_test']:
print(tag)
```
## Changelog
These changelogs are summaries only and not comprehensive. See
the commit history between tags for full changes.
### v3.0.0
- TAG_Byte_Array now returns and accepts `bytearray()`, rather than a list
of bytes (#18).
### v2.0.0
- Py2 is no longer supported.
### v1.4.0
- **Removed** pocket detection helpers and ``RegionFile``, leaving PyNBT to
**only** handle NBT.
- Added a simple unicode test.
### v1.3.0
- Internal cleanups in ``nbt.py`` to ease some C work.
- ``NBTFile.__init__()`` and ``NBTFile.save()``'s arguments have changed.
For most cases changing ``compressed=True`` to ``NBTFIle.Compression.GZIP``
will suffice.
- ``NBTFile.__init__()`` and ``NBTFile.save()`` no longer accept paths,
instead accepting only file-like objects implementing ``read()`` and
``write()``, respectively.
- ``name`` must now be provided at construction or before saving of an
``NBTFile()`` (defaults to ``None`` instead of '').
### v1.2.
- TAG_List's values no longer need to be ``TAG_*`` objects. They
will be converted when the tag is saved. This allows much easier lists of
native types.
### v1.2.0
- Internal code cleanup. Breaks compatibility with pocket loading
and saving (to be reimplemented as helpers).
- Slight speed improvements.
- TAG_List can now be treated as a plain python list (`.value` points to `self`)
### v1.1.0
- Breaks compatibility with older code, but allows much more
convenient creation of `TAG_Compound`. `name` and `value` have in most cases
swapped spots.
- `name` is now the last argument of every `TAG_*`, and
optional for children of a `TAG_Compound`. Instead, they'll be given the key
they're assigned to as a name.
- `TAG_Compound`s can now be treated like
dictionaries for convienience. `.value` simply maps to itself.
### v1.0.1
- Small bugfixes.
- Adds support for `TAG_Int_Array`.
### v1.0.0
- First release.