"""
Create objects in a GRASS project
(C) 2020-2025 by the GRASS Development Team
This program is free software under the GNU General Public
License (>=v2). Read the file COPYING that comes with GRASS
for details.
.. sectionauthor:: Vaclav Petras <wenzeslaus gmail com>
"""
from __future__ import annotations
import json
import tarfile
import codecs
import os
import shutil
import getpass
from pathlib import Path
from grass.grassdb.manage import resolve_mapset_path, MapsetPath
[docs]
def create_xy_project(path: Path | str) -> None:
"""Create a project with with general cartesian coordinate system (XY)
:raises: OSError on error related to the file system
"""
_create_project_dir(path)
# create DEFAULT_WIND and WIND files
_add_computation_region_to_project_dir(path, crs_type_code=0)
def _create_project_dir(path: Path | str) -> Path:
"""Create an empty project directory including directory for the default mapset
:returns: Path to the default mapset
"""
project_dir = Path(path)
permanent_dir = project_dir / "PERMANENT"
project_dir.mkdir()
permanent_dir.mkdir()
return permanent_dir
def _set_project_description(path: Path | str, text: str):
"""Set description (aka title aka MYNAME) for a project"""
with codecs.open(
os.path.join(path, "PERMANENT", "MYNAME"),
encoding="utf-8",
mode="w",
) as fd:
if text:
fd.write(text + os.linesep)
else:
fd.write(os.linesep)
def _add_computation_region_to_project_dir(
path: Path | str, *, crs_type_code: int | None = None, zone: int | None = None
):
"""Add computational region to project directory
Creates both the default and the current compuational regions.
If the file already exists, it is overwritten.
"""
permanent_dir = Path(path) / "PERMANENT"
default_wind_path = permanent_dir / "DEFAULT_WIND"
wind_path = permanent_dir / "WIND"
size: float = 1
regioninfo = [
f"proj: {crs_type_code if crs_type_code is not None else 0}",
f"zone: {zone if zone is not None else 0}",
f"north: {size}",
"south: 0",
f"east: {size}",
"west: 0",
f"cols: {size}",
f"rows: {size}",
"e-w resol: 1",
"n-s resol: 1",
f"top: {size}",
"bottom: 0",
f"cols3: {size}",
f"rows3: {size}",
f"depths: {size}",
"e-w resol3: 1",
"n-s resol3: 1",
"t-b resol: 1",
]
# create the files
default_wind_path.write_text("\n".join(regioninfo))
shutil.copy(default_wind_path, wind_path)
def _directory_to_mapset(path: MapsetPath):
"""Turn an existing directory into a mapset"""
# copy DEFAULT_WIND file and its permissions from PERMANENT
# to WIND in the new mapset
region_path1 = path.path.parent / "PERMANENT" / "DEFAULT_WIND"
region_path2 = path.path / "WIND"
shutil.copy(region_path1, region_path2)
[docs]
def create_mapset(database, location=None, mapset=None):
"""Creates a mapset in a specified location"""
path = resolve_mapset_path(
database,
location,
mapset,
)
# create an empty directory
os.mkdir(path)
_directory_to_mapset(path)
# set permissions to u+rw,go+r (disabled; why?)
# os.chmod(os.path.join(database,location,mapset,'WIND'), 0644)
[docs]
def get_default_mapset_name():
"""Returns default name for mapset."""
try:
result = getpass.getuser()
# Raise error if not ascii (not valid mapset name).
result.encode("ascii")
except UnicodeEncodeError:
# Fall back to fixed name.
result = "user"
return result
[docs]
def create_project_from_pack(
path: Path | str, filename: str, description: str | None = None
):
"""Create project from a GRASS native raster file (aka pack file)"""
_create_project_dir(path)
set_project_crs_from_pack(path, filename)
if description:
_set_project_description(path, description)
[docs]
def set_project_crs_from_pack(path: Path | str, filename: Path | str):
"""Set project CRS from a GRASS native raster file.
Overwrites the values of the current and the default computational region (if any).
"""
with tarfile.open(os.fspath(filename)) as tar:
data_names = [
tarinfo.name for tarinfo in tar.getmembers() if "/" not in tarinfo.name
]
try:
tar_info = tar.getmember(data_names[0] + "/computational_region_crs.json")
except KeyError as error:
msg = "Missing complete CRS info: Use pack from version 8.5 (2025) or above"
raise ValueError(msg) from error
data = json.loads(tar.extractfile(tar_info).read().decode("utf-8"))
_add_computation_region_to_project_dir(
path,
crs_type_code=data["type_code"],
zone=data["zone"],
)
crs_files = [
"PROJ_UNITS",
"PROJ_INFO",
"PROJ_EPSG",
"PROJ_SRID",
"PROJ_WKT",
]
for name in crs_files:
try:
tar_info = tar.getmember(data_names[0] + "/" + name)
except KeyError:
continue
(Path(path) / "PERMANENT" / name).write_bytes(
tar.extractfile(tar_info).read()
)