Source code for whoosh.query.ranges

# Copyright 2007 Matt Chaput. All rights reserved.
#
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# THIS SOFTWARE IS PROVIDED BY MATT CHAPUT ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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# EVENT SHALL MATT CHAPUT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
# OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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from whoosh.query import compound, qcore, terms, wrappers
from whoosh.util.times import datetime_to_long


class RangeMixin:
    # Contains methods shared by TermRange and NumericRange

    def __repr__(self):
        return "{}({!r}, {!r}, {!r}, {}, {}, boost={}, constantscore={})".format(
            self.__class__.__name__,
            self.fieldname,
            self.start,
            self.end,
            self.startexcl,
            self.endexcl,
            self.boost,
            self.constantscore,
        )

    def __str__(self):
        startchar = "{" if self.startexcl else "["
        endchar = "}" if self.endexcl else "]"
        start = "" if self.start is None else self.start
        end = "" if self.end is None else self.end
        return f"{self.fieldname}:{startchar}{start} TO {end}{endchar}"

    def __eq__(self, other):
        return (
            other
            and self.__class__ is other.__class__
            and self.fieldname == other.fieldname
            and self.start == other.start
            and self.end == other.end
            and self.startexcl == other.startexcl
            and self.endexcl == other.endexcl
            and self.boost == other.boost
            and self.constantscore == other.constantscore
        )

    def __hash__(self):
        return (
            hash(self.fieldname)
            ^ hash(self.start)
            ^ hash(self.startexcl)
            ^ hash(self.end)
            ^ hash(self.endexcl)
            ^ hash(self.boost)
        )

    def is_range(self):
        return True

    def _comparable_start(self):
        if self.start is None:
            return (qcore.Lowest, 0)
        else:
            second = 1 if self.startexcl else 0
            return (self.start, second)

    def _comparable_end(self):
        if self.end is None:
            return (qcore.Highest, 0)
        else:
            second = -1 if self.endexcl else 0
            return (self.end, second)

    def overlaps(self, other):
        if not isinstance(other, TermRange):
            return False
        if self.fieldname != other.fieldname:
            return False

        start1 = self._comparable_start()
        start2 = other._comparable_start()
        end1 = self._comparable_end()
        end2 = other._comparable_end()

        return (
            (start1 >= start2 and start1 <= end2)
            or (end1 >= start2 and end1 <= end2)
            or (start2 >= start1 and start2 <= end1)
            or (end2 >= start1 and end2 <= end1)
        )

    def merge(self, other, intersect=True):
        assert self.fieldname == other.fieldname

        start1 = self._comparable_start()
        start2 = other._comparable_start()
        end1 = self._comparable_end()
        end2 = other._comparable_end()

        if start1 >= start2 and end1 <= end2:
            start = start2
            end = end2
        elif start2 >= start1 and end2 <= end1:
            start = start1
            end = end1
        elif intersect:
            start = max(start1, start2)
            end = min(end1, end2)
        else:
            start = min(start1, start2)
            end = max(end1, end2)

        startval = None if start[0] is qcore.Lowest else start[0]
        startexcl = start[1] == 1
        endval = None if end[0] is qcore.Highest else end[0]
        endexcl = end[1] == -1

        boost = max(self.boost, other.boost)
        constantscore = self.constantscore or other.constantscore

        return self.__class__(
            self.fieldname,
            startval,
            endval,
            startexcl,
            endexcl,
            boost=boost,
            constantscore=constantscore,
        )


[docs]class TermRange(RangeMixin, terms.MultiTerm): """Matches documents containing any terms in a given range. >>> # Match documents where the indexed "id" field is greater than or equal >>> # to 'apple' and less than or equal to 'pear'. >>> TermRange("id", u"apple", u"pear") """ def __init__( self, fieldname, start, end, startexcl=False, endexcl=False, boost=1.0, constantscore=True, ): """ :param fieldname: The name of the field to search. :param start: Match terms equal to or greater than this. :param end: Match terms equal to or less than this. :param startexcl: If True, the range start is exclusive. If False, the range start is inclusive. :param endexcl: If True, the range end is exclusive. If False, the range end is inclusive. :param boost: Boost factor that should be applied to the raw score of results matched by this query. """ self.fieldname = fieldname self.start = start self.end = end self.startexcl = startexcl self.endexcl = endexcl self.boost = boost self.constantscore = constantscore def normalize(self): if self.start in ("", None) and self.end in ("\uffff", None): from whoosh.query import Every return Every(self.fieldname, boost=self.boost) elif self.start == self.end: if self.startexcl or self.endexcl: return qcore.NullQuery return terms.Term(self.fieldname, self.start, boost=self.boost) else: return TermRange( self.fieldname, self.start, self.end, self.startexcl, self.endexcl, boost=self.boost, ) # def replace(self, fieldname, oldtext, newtext): # q = self.copy() # if q.fieldname == fieldname: # if q.start == oldtext: # q.start = newtext # if q.end == oldtext: # q.end = newtext # return q def _btexts(self, ixreader): fieldname = self.fieldname field = ixreader.schema[fieldname] startexcl = self.startexcl endexcl = self.endexcl if self.start is None: start = b"" else: try: start = field.to_bytes(self.start) except ValueError: return if self.end is None: end = b"\xFF\xFF\xFF\xFF" else: try: end = field.to_bytes(self.end) except ValueError: return for fname, t in ixreader.terms_from(fieldname, start): if fname != fieldname: break if t == start and startexcl: continue if t == end and endexcl: break if t > end: break yield t
[docs]class NumericRange(RangeMixin, qcore.Query): """ A range query for NUMERIC fields. Takes advantage of tiered indexing to speed up large ranges by matching at a high resolution at the edges of the range and a low resolution in the middle. Example Usage: # Match numbers from 10 to 5925 in the "number" field. nr = NumericRange("number", 10, 5925) Methods: __init__(self, fieldname, start, end, startexcl=False, endexcl=False, boost=1.0, constantscore=True): Initializes a NumericRange object with the specified parameters. simplify(self, ixreader): Simplifies the range query by compiling it and calling the simplify method on the compiled query. estimate_size(self, ixreader): Estimates the size of the range query by compiling it and calling the estimate_size method on the compiled query. estimate_min_size(self, ixreader): Estimates the minimum size of the range query by compiling it and calling the estimate_min_size method on the compiled query. docs(self, searcher): Retrieves the documents that match the range query by compiling it and calling the docs method on the compiled query. _compile_query(self, ixreader): Compiles the range query by preparing the start and end values, generating subqueries for different resolutions, and combining them into a single query. matcher(self, searcher, context=None): Retrieves the matcher for the range query by compiling it and calling the matcher method on the compiled query. Fields: fieldname: The name of the field to search. start: Match terms equal to or greater than this number. This should be a number type, not a string. end: Match terms equal to or less than this number. This should be a number type, not a string. startexcl: If True, the range start is exclusive. If False, the range start is inclusive. endexcl: If True, the range end is exclusive. If False, the range end is inclusive. boost: Boost factor that should be applied to the raw score of results matched by this query. constantscore: If True, the compiled query returns a constant score (the value of the boost keyword argument) instead of actually scoring the matched terms. This gives a nice speed boost and won't affect the results in most cases since numeric ranges will almost always be used as a filter. """
[docs] def __init__( self, fieldname, start, end, startexcl=False, endexcl=False, boost=1.0, constantscore=True, ): """ :param fieldname: The name of the field to search. :param start: Match terms equal to or greater than this number. This should be a number type, not a string. :param end: Match terms equal to or less than this number. This should be a number type, not a string. :param startexcl: If True, the range start is exclusive. If False, the range start is inclusive. :param endexcl: If True, the range end is exclusive. If False, the range end is inclusive. :param boost: Boost factor that should be applied to the raw score of results matched by this query. :param constantscore: If True, the compiled query returns a constant score (the value of the ``boost`` keyword argument) instead of actually scoring the matched terms. This gives a nice speed boost and won't affect the results in most cases since numeric ranges will almost always be used as a filter. """ self.fieldname = fieldname self.start = start self.end = end self.startexcl = startexcl self.endexcl = endexcl self.boost = boost self.constantscore = constantscore
# NumericRange should raise an error if the start and end parameters are not numeric. # Some of the old tests fail if this is enabled. We need to confirm if this is a bug or not. # if not isinstance(self.start, (int, float)): # raise ValueError("NumericRange: start parameter must be numeric") # if not isinstance(self.end, (int, float)): # raise ValueError("NumericRange: end parameter must be numeric")
[docs] def simplify(self, ixreader): return self._compile_query(ixreader).simplify(ixreader)
[docs] def estimate_size(self, ixreader): return self._compile_query(ixreader).estimate_size(ixreader)
[docs] def estimate_min_size(self, ixreader): return self._compile_query(ixreader).estimate_min_size(ixreader)
[docs] def docs(self, searcher): q = self._compile_query(searcher.reader()) return q.docs(searcher)
[docs] def _compile_query(self, ixreader): from whoosh.fields import NUMERIC from whoosh.util.numeric import tiered_ranges field = ixreader.schema[self.fieldname] if not isinstance(field, NUMERIC): raise ValueError(f"NumericRange: field {self.fieldname} is not numeric") start = self.start if start is not None: start = field.prepare_number(start) end = self.end if end is not None: end = field.prepare_number(end) subqueries = [] stb = field.sortable_to_bytes # Get the term ranges for the different resolutions ranges = tiered_ranges( field.numtype, field.bits, field.signed, start, end, field.shift_step, self.startexcl, self.endexcl, ) for startnum, endnum, shift in ranges: if startnum == endnum: subq = terms.Term(self.fieldname, stb(startnum, shift)) else: startbytes = stb(startnum, shift) endbytes = stb(endnum, shift) subq = TermRange(self.fieldname, startbytes, endbytes) subqueries.append(subq) if len(subqueries) == 1: q = subqueries[0] elif subqueries: q = compound.Or(subqueries, boost=self.boost) else: return qcore.NullQuery if self.constantscore: q = wrappers.ConstantScoreQuery(q, self.boost) return q
[docs] def matcher(self, searcher, context=None): q = self._compile_query(searcher.reader()) return q.matcher(searcher, context)
[docs]class DateRange(NumericRange): """This is a very thin subclass of :class:`NumericRange` that only overrides the initializer and ``__repr__()`` methods to work with datetime objects instead of numbers. Internally this object converts the datetime objects it's created with to numbers and otherwise acts like a ``NumericRange`` query. >>> DateRange("date", datetime(2010, 11, 3, 3, 0), ... datetime(2010, 11, 3, 17, 59)) """ def __init__( self, fieldname, start, end, startexcl=False, endexcl=False, boost=1.0, constantscore=True, ): self.startdate = start self.enddate = end if start: start = datetime_to_long(start) if end: end = datetime_to_long(end) super().__init__( fieldname, start, end, startexcl=startexcl, endexcl=endexcl, boost=boost, constantscore=constantscore, ) def __repr__(self): return "{}({!r}, {!r}, {!r}, {}, {}, boost={})".format( self.__class__.__name__, self.fieldname, self.startdate, self.enddate, self.startexcl, self.endexcl, self.boost, )