Fuzzy attributes

Note

Now that FactoryBoy includes the factory.Faker class, most of these built-in fuzzers are deprecated in favor of their Faker equivalents. Further discussion in issue 271.

Some tests may be interested in testing with fuzzy, random values.

This is handled by the factory.fuzzy module, which provides a few random declarations.

Note

Use import factory.fuzzy to load this module.

FuzzyAttribute

class factory.fuzzy.FuzzyAttribute[source]

The FuzzyAttribute uses an arbitrary callable as fuzzer. It is expected that successive calls of that function return various values.

fuzzer: The callable that generates random values

FuzzyText

class factory.fuzzy.FuzzyText(length=12, chars=string.ascii_letters, prefix='')[source]

The FuzzyText fuzzer yields random strings beginning with the given prefix, followed by length characters chosen from the chars character set, and ending with the given suffix.

length: int, the length of the random part

prefix: text, an optional prefix to prepend to the random part

suffix: text, an optional suffix to append to the random part

chars

char iterable, the chars to choose from; defaults to the list of ascii: letters and numbers.

FuzzyChoice

class factory.fuzzy.FuzzyChoice(choices)[source]

The FuzzyChoice fuzzer yields random choices from the given iterable.

Note

The passed in choices will be converted into a list upon first use, not at declaration time.

This allows passing in, for instance, a Django queryset that will only hit the database during the database, not at import time.

choices: The list of choices to select randomly

FuzzyInteger

class factory.fuzzy.FuzzyInteger(low[, high[, step]])[source]

The FuzzyInteger fuzzer generates random integers within a given inclusive range.

The low bound may be omitted, in which case it defaults to 0:

>>> fi = FuzzyInteger(0, 42)
>>> fi.low, fi.high
0, 42

>>> fi = FuzzyInteger(42)
>>> fi.low, fi.high
0, 42

low: int, the inclusive lower bound of generated integers

high: int, the inclusive higher bound of generated integers

step: int, the step between values in the range; for instance, a FuzzyInteger(0, 42, step=3) might only yield values from [0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42].

FuzzyDecimal

class factory.fuzzy.FuzzyDecimal(low[, high[, precision=2]])[source]

The FuzzyDecimal fuzzer generates random decimals within a given inclusive range.

The low bound may be omitted, in which case it defaults to 0:

>>> FuzzyDecimal(0.5, 42.7)
>>> fi.low, fi.high
0.5, 42.7

>>> fi = FuzzyDecimal(42.7)
>>> fi.low, fi.high
0.0, 42.7

>>> fi = FuzzyDecimal(0.5, 42.7, 3)
>>> fi.low, fi.high, fi.precision
0.5, 42.7, 3

low: decimal, the inclusive lower bound of generated decimals

high: decimal, the inclusive higher bound of generated decimals

precision
int, the number of digits to generate after the dot. The default is 2 digits.

FuzzyFloat

class factory.fuzzy.FuzzyFloat(low[, high])[source]

The FuzzyFloat fuzzer provides random float objects within a given inclusive range.

>>> FuzzyFloat(0.5, 42.7)
>>> fi.low, fi.high
0.5, 42.7

>>> fi = FuzzyFloat(42.7)
>>> fi.low, fi.high
0.0, 42.7

low: decimal, the inclusive lower bound of generated floats

high: decimal, the inclusive higher bound of generated floats

FuzzyDate

class factory.fuzzy.FuzzyDate(start_date[, end_date])[source]

The FuzzyDate fuzzer generates random dates within a given inclusive range.

The end_date bound may be omitted, in which case it defaults to the current date:

>>> fd = FuzzyDate(datetime.date(2008, 1, 1))
>>> fd.start_date, fd.end_date
datetime.date(2008, 1, 1), datetime.date(2013, 4, 16)

start_date: datetime.date, the inclusive lower bound of generated dates

end_date: datetime.date, the inclusive higher bound of generated dates

FuzzyDateTime

class factory.fuzzy.FuzzyDateTime(start_dt, [end_dt, ]force_year=None, force_month=None, force_day=None, force_hour=None, force_minute=None, force_second=None, force_microsecond=None)[source]

The FuzzyDateTime fuzzer generates random timezone-aware datetime within a given inclusive range.

The end_dt bound may be omitted, in which case it defaults to datetime.datetime.now() localized into the UTC timezone.

>>> fdt = FuzzyDateTime(datetime.datetime(2008, 1, 1, tzinfo=UTC))
>>> fdt.start_dt, fdt.end_dt
datetime.datetime(2008, 1, 1, tzinfo=UTC), datetime.datetime(2013, 4, 21, 19, 13, 32, 458487, tzinfo=UTC)

The force_XXX keyword arguments force the related value of generated datetimes:

>>> fdt = FuzzyDateTime(datetime.datetime(2008, 1, 1, tzinfo=UTC), datetime.datetime(2009, 1, 1, tzinfo=UTC),
...     force_day=3, force_second=42)
>>> fdt.evaluate(2, None, False)  # Actual code used by ``SomeFactory.build()``
datetime.datetime(2008, 5, 3, 12, 13, 42, 124848, tzinfo=UTC)

start_dt: datetime.datetime, the inclusive lower bound of generated datetimes

end_dt: datetime.datetime, the inclusive upper bound of generated datetimes

force_year: int or None; if set, forces the year of generated datetime.

force_month: int or None; if set, forces the month of generated datetime.

force_day: int or None; if set, forces the day of generated datetime.

force_hour: int or None; if set, forces the hour of generated datetime.

force_minute: int or None; if set, forces the minute of generated datetime.

force_second: int or None; if set, forces the second of generated datetime.

force_microsecond: int or None; if set, forces the microsecond of generated datetime.

FuzzyNaiveDateTime

class factory.fuzzy.FuzzyNaiveDateTime(start_dt, [end_dt, ]force_year=None, force_month=None, force_day=None, force_hour=None, force_minute=None, force_second=None, force_microsecond=None)[source]

The FuzzyNaiveDateTime fuzzer generates random naive datetime within a given inclusive range.

The end_dt bound may be omitted, in which case it defaults to datetime.datetime.now():

>>> fdt = FuzzyNaiveDateTime(datetime.datetime(2008, 1, 1))
>>> fdt.start_dt, fdt.end_dt
datetime.datetime(2008, 1, 1), datetime.datetime(2013, 4, 21, 19, 13, 32, 458487)

The force_XXX keyword arguments force the related value of generated datetimes:

>>> fdt = FuzzyNaiveDateTime(datetime.datetime(2008, 1, 1), datetime.datetime(2009, 1, 1),
...     force_day=3, force_second=42)
>>> fdt.evaluate(2, None, False)  # Actual code used by ``SomeFactory.build()``
datetime.datetime(2008, 5, 3, 12, 13, 42, 124848)

start_dt: datetime.datetime, the inclusive lower bound of generated datetimes

end_dt: datetime.datetime, the inclusive upper bound of generated datetimes

force_year: int or None; if set, forces the year of generated datetime.

force_month: int or None; if set, forces the month of generated datetime.

force_day: int or None; if set, forces the day of generated datetime.

force_hour: int or None; if set, forces the hour of generated datetime.

force_minute: int or None; if set, forces the minute of generated datetime.

force_second: int or None; if set, forces the second of generated datetime.

force_microsecond: int or None; if set, forces the microsecond of generated datetime.

Custom fuzzy fields

Alternate fuzzy fields may be defined. They should inherit from the BaseFuzzyAttribute class, and override its fuzz() method.

class factory.fuzzy.BaseFuzzyAttribute[source]

Base class for all fuzzy attributes.

fuzz(self)[source]: The method responsible for generating random values. Must be overridden in subclasses.

Warning

Custom BaseFuzzyAttribute subclasses MUST use factory.random.randgen as a randomness source; this ensures that data they generate can be regenerated using the simple state from factory.random.get_random_state().