Coverage for python/lsst/daf/persistence/storageInterface.py : 87%
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#!/usr/bin/env python
# # LSST Data Management System # Copyright 2017 LSST Corporation. # # This product includes software developed by the # LSST Project (http://www.lsst.org/). # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the LSST License Statement and # the GNU General Public License along with this program. If not, # see <http://www.lsstcorp.org/LegalNotices/>. #
"""Defines the interface for a connection to a Storage location.
Parameters ---------- uri : string URI or path that is used as the storage location. create : bool If True The StorageInterface subclass should create a new repository at the root location. If False then a new repository will not be created.
Raises ------ NoRepositroyAtRoot If create is False and a repository does not exist at the root specified by uri then NoRepositroyAtRoot is raised. """
"""initialzer""" pass
def _readFormatters(cls): """Getter for the container of read formatters of a StorageInterface subclass.
Returns ------- dict The read formatters container belonging to the class type. """
def _writeFormatters(cls): """Getter for the container of write formatters of a StorageInterface subclass.
Returns ------- dict The write formatters container belonging to the class type. """
def getReadFormatter(cls, objType): """Search in the registered formatters for the objType read formatter.
Parameters ---------- objType : class type The type of class to find a formatter for.
Returns ------- formatter callable The formatter callable used to read the object from the storageInterface. """ return cls._readFormatters().get(objType, None)
def getWriteFormatter(cls, objType): """Search in the registered formatters for the objType write formatter.
Parameters ---------- objType : class type The type of class to find a formatter for.
Returns ------- formatter callable The formatter callable used to write the object to the storageInterface. """ return cls._writeFormatters().get(objType, None)
"""Register read and/or write formatters for a storageInterface subclass
Parameters ---------- cls : StorageInterface subclass The type of StorageInterface the formatter is being registered for. formatable : class object The class object whose instances can be formatted by the formatter. readFormatter : a read formatter callable The formatter function that can be used by the StorageInterface instance to read the object from the storage. writeFormatter : a write formatter callable The formatter function that can be used by the StorageInterface instance to write the object to the storage.
Raises ------ RuntimeError For each object type and StorageInterface subclass the read and write formatters should only be registered once. If a second registration occurs for either a RuntimeError is raised. """ raise RuntimeError(("Registration of second formatter {} for formattable {} in " + " storageInterface {}").format(formatter, formatable, storageInterface))
def write(self, butlerLocation, obj): """Writes an object to a location and persistence format specified by ButlerLocation
Parameters ---------- butlerLocation : ButlerLocation The location & formatting for the object to be written. obj : object instance The object to be written. """
def read(self, butlerLocation): """Read from a butlerLocation.
Parameters ---------- butlerLocation : ButlerLocation The location & formatting for the object(s) to be read.
Returns ------- A list of objects as described by the butler location. One item for each location in butlerLocation.getLocations() """
def getLocalFile(self, path): """Get a handle to a local copy of the file, downloading it to a temporary if needed.
Parameters ---------- path : string A path to the the file in storage, relative to root.
Returns ------- A handle to a local copy of the file. If storage is remote it will be a temporary file. If storage is local it may be the original file or a temporary file. The file name can be gotten via the 'name' property of the returned object. """
def exists(self, location): """Check if location exists.
Parameters ---------- location : ButlerLocation or string A a string or a ButlerLocation that describes the location of an object in this storage.
Returns ------- bool True if exists, else False. """
def instanceSearch(self, path): """Search for the given path in this storage instance.
If the path contains an HDU indicator (a number in brackets before the dot, e.g. 'foo.fits[1]', this will be stripped when searching and so will match filenames without the HDU indicator, e.g. 'foo.fits'. The path returned WILL contain the indicator though, e.g. ['foo.fits[1]'].
Parameters ---------- path : string A filename (and optionally prefix path) to search for within root.
Returns ------- string or None The location that was found, or None if no location was found. """
def search(cls, root, path): """Look for the given path in the current root.
Also supports searching for the path in Butler v1 repositories by following the Butler v1 _parent symlink
If the path contains an HDU indicator (a number in brackets, e.g. 'foo.fits[1]', this will be stripped when searching and so will match filenames without the HDU indicator, e.g. 'foo.fits'. The path returned WILL contain the indicator though, e.g. ['foo.fits[1]'].
Parameters ---------- root : string The path to the root directory. path : string The path to the file within the root directory.
Returns ------- string or None The location that was found, or None if no location was found. """
def copyFile(self, fromLocation, toLocation): """Copy a file from one location to another on the local filesystem.
Parameters ---------- fromLocation : string Path and name of existing file. toLocation : string Path and name of new file.
Returns ------- None """
def locationWithRoot(self, location): """Get the full path to the location.
Parameters ---------- location : string Path to a location within the repository relative to repository root.
Returns ------- string Absolute path to to the locaiton within the repository. """
def getRepositoryCfg(cls, uri): """Get a persisted RepositoryCfg
Parameters ---------- uri : URI or path to a RepositoryCfg Description
Returns ------- A RepositoryCfg instance or None """
"""Serialize a RepositoryCfg to a location.
When loc == cfg.root, the RepositoryCfg is to be written at the root location of the repository. In that case, root is not written, it is implicit in the location of the cfg. This allows the cfg to move from machine to machine without modification.
Parameters ---------- cfg : RepositoryCfg instance The RepositoryCfg to be serailized. loc : string, optional The URI location (can be relative path) to write the RepositoryCfg. If loc is None, the location will be read from the root parameter of loc.
Returns ------- None """
def getMapperClass(cls, root): """Get the mapper class associated with a repository root.
Parameters ---------- root : string The location of a persisted RepositoryCfg is (new style repos).
Returns ------- A class object or a class instance, depending on the state of the mapper when the repository was created. """
# Optional: Only needs to work if relative paths are sensical on this # storage type and for the case where fromPath and toPath are of the same # storage type. def relativePath(cls, fromPath, toPath): """Get a relative path from a location to a location.
Parameters ---------- fromPath : string A path at which to start. It can be a relative path or an absolute path. toPath : string A target location. It can be a relative path or an absolute path.
Returns ------- string A relative path that describes the path from fromPath to toPath. """ return toPath
# Optional: Only needs to work if relative paths and absolute paths are # sensical on this storage type and for the case where fromPath and toPath # are of the same storage type. def absolutePath(cls, fromPath, relativePath): """Get an absolute path for the path from fromUri to toUri
Parameters ---------- fromPath : the starting location A location at which to start. It can be a relative path or an absolute path. relativePath : the location relative to fromPath A relative path.
Returns ------- string Path that is an absolute path representation of fromPath + relativePath, if one exists. If relativePath is absolute or if fromPath is not related to relativePath then relativePath will be returned. """ return relativePath |