"""Data interface functions for the mudpy engine.""" # Copyright (c) 2004-2016 Jeremy Stanley . Permission # to use, copy, modify, and distribute this software is granted under # terms provided in the LICENSE file distributed with this software. import os import re import stat import mudpy import yaml class DataFile: """A file containing universe elements and their facets.""" def __init__(self, filename, universe): self.filename = filename self.universe = universe self.data = {} self.load() def load(self): """Read a file, create elements and poplulate facets accordingly.""" self.modified = False try: self.data = yaml.safe_load(open(self.filename)) except FileNotFoundError: # it's normal if the file is one which doesn't exist yet log_entry = ("File %s is unavailable." % self.filename, 6) try: mudpy.misc.log(*log_entry) except NameError: # happens when we're not far enough along in the init process self.universe.setup_loglines.append(log_entry) if not hasattr(self.universe, "files"): self.universe.files = {} self.universe.files[self.filename] = self includes = [] if "__control__" in self.data: if "include_files" in self.data["__control__"]: for included in self.data["__control__"]["include_files"]: included = find_file( included, relative=self.filename, universe=self.universe) if included not in includes: includes.append(included) if "include_dirs" in self.data["__control__"]: for included in [ os.path.join(x, "__init__.yaml") for x in self.data["__control__"]["include_dirs"] ]: included = find_file( included, relative=self.filename, universe=self.universe ) if included not in includes: includes.append(included) if "default_files" in self.data["__control__"]: origins = self.data["__control__"]["default_files"] for key in origins.keys(): origins[key] = find_file( origins[key], relative=self.filename, universe=self.universe ) if origins[key] not in includes: includes.append(origins[key]) self.universe.default_origins[key] = origins[key] if key not in self.universe.categories: self.universe.categories[key] = {} if "private_files" in self.data["__control__"]: for item in self.data["__control__"]["private_files"]: item = find_file( item, relative=self.filename, universe=self.universe ) if item not in includes: includes.append(item) if item not in self.universe.private_files: self.universe.private_files.append(item) for node in list(self.data): if node == "__control__": continue facet_pos = node.rfind(".") + 1 if not facet_pos: mudpy.misc.Element(node, self.universe, self.filename, old_style=True) else: prefix = node[:facet_pos].strip(".") try: element = self.universe.contents[prefix] except KeyError: element = mudpy.misc.Element(prefix, self.universe, self.filename) element.set(node[facet_pos:], self.data[node]) if prefix.startswith("mudpy.movement."): self.universe.directions.add( prefix[prefix.rfind(".") + 1:]) for include_file in includes: if not os.path.isabs(include_file): include_file = find_file( include_file, relative=self.filename, universe=self.universe ) if (include_file not in self.universe.files or not self.universe.files[include_file].is_writeable()): DataFile(include_file, self.universe) def save(self): """Write the data, if necessary.""" normal_umask = 0o0022 private_umask = 0o0077 private_file_mode = 0o0600 # when modified, writeable and has content or the file exists if self.modified and self.is_writeable() and ( self.data or os.path.exists(self.filename) ): # make parent directories if necessary if not os.path.exists(os.path.dirname(self.filename)): old_umask = os.umask(normal_umask) os.makedirs(os.path.dirname(self.filename)) os.umask(old_umask) # backup the file if "__control__" in self.data and "backup_count" in self.data[ "__control__"]: max_count = self.data["__control__"]["backup_count"] else: max_count = self.universe.contents["mudpy.limit"].get( "backups") if os.path.exists(self.filename) and max_count: backups = [] for candidate in os.listdir(os.path.dirname(self.filename)): if re.match( os.path.basename(self.filename) + """\.\d+$""", candidate ): backups.append(int(candidate.split(".")[-1])) backups.sort() backups.reverse() for old_backup in backups: if old_backup >= max_count - 1: os.remove(self.filename + "." + str(old_backup)) elif not os.path.exists( self.filename + "." + str(old_backup + 1) ): os.rename( self.filename + "." + str(old_backup), self.filename + "." + str(old_backup + 1) ) if not os.path.exists(self.filename + ".0"): os.rename(self.filename, self.filename + ".0") # our data file if self.filename in self.universe.private_files: old_umask = os.umask(private_umask) file_descriptor = open(self.filename, "w") if oct(stat.S_IMODE(os.stat( self.filename)[stat.ST_MODE])) != private_file_mode: # if it's marked private, chmod it appropriately os.chmod(self.filename, private_file_mode) else: old_umask = os.umask(normal_umask) file_descriptor = open(self.filename, "w") os.umask(old_umask) # write and close the file yaml.safe_dump(self.data, allow_unicode=True, default_flow_style=False, stream=file_descriptor) file_descriptor.close() # unset the modified flag self.modified = False def is_writeable(self): """Returns True if the __control__ read_only is False.""" try: return not self.data["__control__"].get("read_only", False) except KeyError: return True def find_file( file_name=None, root_path=None, search_path=None, default_dir=None, relative=None, universe=None ): """Return an absolute file path based on configuration.""" # make sure to get rid of any surrounding quotes first thing if file_name: file_name = file_name.strip("\"'") # this is all unnecessary if it's already absolute if file_name and os.path.isabs(file_name): return os.path.realpath(file_name) # if a universe was provided, try to get some defaults from there if universe: if hasattr( universe, "contents" ) and "internal:storage" in universe.contents: storage = universe.categories["internal"]["storage"] if not root_path: root_path = storage.get("root_path").strip("\"'") if not search_path: search_path = storage.get("search_path") if not default_dir: default_dir = storage.get("default_dir").strip("\"'") # if there's only one file loaded, try to work around a chicken