Source code for stetl.filters.stringfilter

# String filtering.
#
# Author:Just van den Broecke

from stetl.component import Config
from stetl.util import Util
from stetl.filter import Filter
from stetl.packet import FORMAT

log = Util.get_log("stringfilter")


[docs] class StringFilter(Filter): """ Base class for any string filtering """ # Constructor def __init__(self, configdict, section, consumes, produces): Filter.__init__(self, configdict, section, consumes, produces)
[docs] def invoke(self, packet): if packet.data is None: return packet return self.filter_string(packet)
def filter_string(self, packet): pass
[docs] class StringSubstitutionFilter(StringFilter): """ String filtering using Python advanced String formatting. String should have substitutable values like {schema} {foo} format_args should be of the form format_args = schema:test foo:bar ... consumes=FORMAT.string, produces=FORMAT.string """
[docs] @Config(ptype=str, default=None, required=True) def format_args(self): """ Provides a list of format arguments used by the string substitution filter. Formatting of content according to Python String.format(). String should have substitutable values like {schema} {foo}. Example: format_args = schema:test foo:bar """ pass
[docs] @Config(ptype=str, default=':', required=False) def separator(self): """ Provides the separator to split the format argument names from their values. """ pass
# Constructor def __init__(self, configdict, section): StringFilter.__init__(self, configdict, section, consumes=FORMAT.string, produces=FORMAT.string) # Convert string to dict: http://stackoverflow.com/a/1248990 self.format_args_dict = Util.string_to_dict(self.format_args, self.separator) def filter_string(self, packet): # String substitution based on Python String.format() packet.data = packet.data.format(**self.format_args_dict) return packet
[docs] class StringConcatFilter(StringFilter): """ Concatenates a specified string with the input string (packet.data) either/or as prefix (prepend) or postfix (append) and outputs that concatenation. consumes=FORMAT.string, produces=FORMAT.string """
[docs] @Config(ptype=str, default=None, required=False) def append_string(self): """ String to be appended. Example: append_string = /002PND150904.xml """ pass
[docs] @Config(ptype=str, default=None, required=False) def prepend_string(self): """ String to be prepended. Example: prepend_string = /vsizip/ """ pass
# Constructor def __init__(self, configdict, section): StringFilter.__init__(self, configdict, section, consumes=FORMAT.string, produces=FORMAT.string) def filter_string(self, packet): if not packet.data: return if self.append_string: packet.data = packet.data + self.append_string if self.prepend_string: packet.data = self.prepend_string + packet.data return packet