Source code for fsspec.generic

import inspect
import logging

from .asyn import AsyncFileSystem
from .callbacks import _DEFAULT_CALLBACK
from .core import filesystem, get_filesystem_class, split_protocol

_generic_fs = {}
logger = logging.getLogger("fsspec.generic")


def set_generic_fs(protocol, **storage_options):
    _generic_fs[protocol] = filesystem(protocol, **storage_options)


default_method = "default"


def _resolve_fs(url, method=None, protocol=None, storage_options=None):
    """Pick instance of backend FS"""
    method = method or default_method
    protocol = protocol or split_protocol(url)[0]
    storage_options = storage_options or {}
    if method == "default":
        return filesystem(protocol)
    if method == "generic":
        return _generic_fs[protocol]
    if method == "current":
        cls = get_filesystem_class(protocol)
        return cls.current()
    if method == "options":
        return filesystem(protocol, **storage_options.get(protocol, {}))
    raise ValueError(f"Unknown FS resolution method: {method}")


[docs]def rsync( source, destination, delete_missing=False, source_field="size", dest_field="size", update_cond="different", inst_kwargs=None, fs=None, **kwargs, ): """Sync files between two directory trees (experimental) Parameters ---------- source: str Root of the directory tree to take files from. destination: str Root path to copy into. The contents of this location should be identical to the contents of ``source`` when done. delete_missing: bool If there are paths in the destination that don't exist in the source and this is True, delete them. Otherwise, leave them alone. source_field: str If ``update_field`` is "different", this is the key in the info of source files to consider for difference. dest_field: str If ``update_field`` is "different", this is the key in the info of destination files to consider for difference. update_cond: "different"|"always"|"never" If "always", every file is copied, regardless of whether it exists in the destination. If "never", files that exist in the destination are not copied again. If "different" (default), only copy if the info fields given by ``source_field`` and ``dest_field`` (usually "size") are different. Other comparisons may be added in the future. inst_kwargs: dict|None If ``fs`` is None, use this set of keyword arguments to make a GenericFileSystem instance fs: GenericFileSystem|None Instance to use if explicitly given. The instance defines how to to make downstream file system instances from paths. """ fs = fs or GenericFileSystem(**(inst_kwargs or {})) source = fs._strip_protocol(source) destination = fs._strip_protocol(destination) allfiles = fs.find(source, withdirs=True, detail=True) if not fs.isdir(source): raise ValueError("Can only rsync on a directory") otherfiles = fs.find(destination, withdirs=True, detail=True) dirs = [ a for a, v in allfiles.items() if v["type"] == "directory" and a.replace(source, destination) not in otherfiles ] logger.debug(f"{len(dirs)} directories to create") for dirn in dirs: # no async fs.mkdirs(dirn.replace(source, destination), exist_ok=True) allfiles = {a: v for a, v in allfiles.items() if v["type"] == "file"} logger.debug(f"{len(allfiles)} files to consider for copy") to_delete = [ o for o, v in otherfiles.items() if o.replace(destination, source) not in allfiles and v["type"] == "file" ] for k, v in allfiles.copy().items(): otherfile = k.replace(source, destination) if otherfile in otherfiles: if update_cond == "always": allfiles[k] = otherfile elif update_cond == "different": if v[source_field] != otherfiles[otherfile][dest_field]: # details mismatch, make copy allfiles[k] = otherfile else: # details match, don't copy allfiles.pop(k) else: # file not in target yet allfiles[k] = otherfile if allfiles: source_files, target_files = zip(*allfiles.items()) logger.debug(f"{len(source_files)} files to copy") fs.cp(source_files, target_files, **kwargs) if delete_missing: logger.debug(f"{len(to_delete)} files to delete") fs.rm(to_delete)
[docs]class GenericFileSystem(AsyncFileSystem): """Wrapper over all other FS types <experimental!> This implementation is a single unified interface to be able to run FS operations over generic URLs, and dispatch to the specific implementations using the URL protocol prefix. Note: instances of this FS are always async, even if you never use it with any async backend. """ protocol = "generic" # there is no real reason to ever use a protocol with this FS def __init__(self, default_method="default", **kwargs): """ Parameters ---------- default_method: str (optional) Defines how to configure backend FS instances. Options are: - "default": instantiate like FSClass(), with no extra arguments; this is the default instance of that FS, and can be configured via the config system - "generic": takes instances from the `_generic_fs` dict in this module, which you must populate before use. Keys are by protocol - "current": takes the most recently instantiated version of each FS """ self.method = default_method super(GenericFileSystem, self).__init__(**kwargs) def _strip_protocol(self, path): # normalization only fs = _resolve_fs(path, self.method) return fs.unstrip_protocol(fs._strip_protocol(path)) async def _find(self, path, maxdepth=None, withdirs=False, detail=False, **kwargs): fs = _resolve_fs(path, self.method) if fs.async_impl: out = await fs._find( path, maxdepth=maxdepth, withdirs=withdirs, detail=detail, **kwargs ) else: out = fs.find( path, maxdepth=maxdepth, withdirs=withdirs, detail=detail, **kwargs ) result = {} for k, v in out.items(): name = fs.unstrip_protocol(k) v["name"] = name result[name] = v if detail: return result return list(result) async def _info(self, url, **kwargs): fs = _resolve_fs(url, self.method) if fs.async_impl: out = await fs._info(url, **kwargs) else: out = fs.info(url, **kwargs) out["name"] = fs.unstrip_protocol(out["name"]) return out async def _ls( self, url, detail=True, **kwargs, ): fs = _resolve_fs(url, self.method) if fs.async_impl: out = await fs._ls(url, detail=True, **kwargs) else: out = fs.ls(url, detail=True, **kwargs) for o in out: o["name"] = fs.unstrip_protocol(o["name"]) if detail: return out else: return [o["name"] for o in out] async def _cat_file( self, url, **kwargs, ): fs = _resolve_fs(url, self.method) if fs.async_impl: return await fs._cat_file(url, **kwargs) else: return fs.cat_file(url, **kwargs) async def _pipe_file( self, path, value, **kwargs, ): fs = _resolve_fs(path, self.method) if fs.async_impl: return await fs._pipe_file(path, value, **kwargs) else: return fs.pipe_file(path, value, **kwargs) async def _rm(self, url, **kwargs): fs = _resolve_fs(url, self.method) if fs.async_impl: await fs._rm(url, **kwargs) else: fs.rm(url, **kwargs) async def _makedirs(self, path, exist_ok=False): fs = _resolve_fs(path, self.method) if fs.async_impl: await fs._makedirs(path, exist_ok=exist_ok) else: fs.makedirs(path, exist_ok=exist_ok) def rsync(self, source, destination, **kwargs): """Sync files between two directory trees See `func:rsync` for more details. """ rsync(source, destination, fs=self, **kwargs) async def _cp_file( self, url, url2, blocksize=2**20, callback=_DEFAULT_CALLBACK, **kwargs, ): fs = _resolve_fs(url, self.method) fs2 = _resolve_fs(url2, self.method) if fs is fs2: # pure remote if fs.async_impl: return await fs._cp_file(url, url2, **kwargs) else: return fs.cp_file(url, url2, **kwargs) kw = {"blocksize": 0, "cache_type": "none"} try: f1 = ( await fs.open_async(url, "rb") if hasattr(fs, "open_async") else fs.open(url, "rb", **kw) ) callback.set_size(await maybe_await(f1.size)) f2 = ( await fs2.open_async(url2, "wb") if hasattr(fs2, "open_async") else fs2.open(url2, "wb", **kw) ) while f1.size is None or f2.tell() < f1.size: data = await maybe_await(f1.read(blocksize)) if f1.size is None and not data: break await maybe_await(f2.write(data)) callback.absolute_update(f2.tell()) finally: try: await maybe_await(f2.close()) await maybe_await(f1.close()) except NameError: # fail while opening f1 or f2 pass
async def maybe_await(cor): if inspect.iscoroutine(cor): return await cor else: return cor