6.4

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CreateCacheFilename v1

../_images/CreateCacheFilename-v1_dlg.png

CreateCacheFilename dialog.

Summary

Create cache filename

Properties

Name Direction Type Default Description
PropertyManager Input string   Name of a property manager from which properties are extracted from
Properties Input str list   A list of property names to be included
OtherProperties Input str list   A list of key=value strings for other properties not in the property manager
Prefix Input string   prefix for the output file name
CacheDir Input string   Directory storing cache files for reuse, in-lieu of repetitive, time-consuming calculations
OutputFilename Output string   Full path of output file name
OutputSignature Output string   sha1 string, 40 characters long

Description

The purpose of this algorithm is to create a unique filename for a cache so that a workflow can reuse results from previous computations.

The algorithm will accept a prefix, PropertyManager, list of properties to use from the property manager (empty is use all), and a string array (or List) of other properties to use, and a directory for cache files to exist in (default described below).

The list of property names will be used to select which of the properties in the PropertyManager will be used to calculate the hash and will be interpreted as globbing.

The string array of other_properties will be key/value pairs of properties that should be considered, but are not in the provided PropertyManager.

If a directory is not specified, cache files will go into a cache subdirectory of ConfigService.getUserPropertiesDir(). On unix this will be ~/.mantid/cache.

The algorithm will convert all properties to strings as "%s=%s" % (property.name, property.valueAsStr), sort the list, then convert it to a sha1.

A filename with the form <location>/<prefix>_<sha1>.nxs will be returned as the output property. If no prefix is specified then file result will be <location>/<sha1>.nxs.

  • PropertyManager: an instance of PropertyManager from which property values can be retrieved. None means we don’t care about property manager – all properties will come from other_properties
  • Properties: a list of strings. each string is a property managed by the given property_manager, or it can be glob pattern to match prop names too. but empty list means taking all properties from the property_manager
  • OtherProperties: a list of strings. each string is in the form of key=value for one property not managed by the property_manager. no globbing here.
  • Prefix: prefix to the output hash name. when it is empty, just the hash. when it is not empty, it will be <prefix>_<sha1>
  • CacheDir: the directory in which the cache file will be created. empty string means default as described above

Usage

Example:

import mantid
from mantid.kernel import PropertyManager
pm = PropertyManager()
aprops = ["a", "alibaba", "taa", "sa", "a75"]
props = aprops + ['b', 'c', 'd']
for p in props:
    pm.declareProperty(p, '')
    pm.setProperty(p, "fish")
    continue
mantid.PropertyManagerDataService.add("excreatecachefilename", pm)
other_props = [f'{key}={val}' for key, val in
               {"A": 1, "B": 2}.items()]
# Execute
cache_path, signature = CreateCacheFilename(
    PropertyManager = "excreatecachefilename",
    Properties = ['*a*'],
    OtherProperties = other_props,
    )