a buildbot builders sorter which can prioritize builders that take longer

bonus_sorted.py

from datetime import datetime, timedelta

from dateutil.tz import tzutc

from twisted.internet import defer


# this stores bonuses for builders, which takes in account longer build time
builder_bonuses = {
    'bldr1': timedelta(hours=1)
}

@defer.inlineCallbacks
def BuilderSorter(master, builders):
    # perform an asynchronous schwarzian transform, transforming None
    # into a really big date, so that any
    # date set to 'None' will appear at the
    # end of the list during comparisons.
    max_time = datetime.max
    # Need to set the timezone on the date, in order
    # to perform comparisons with other dates which
    # have the time zone set.
    max_time = max_time.replace(tzinfo=tzutc())

    @defer.inlineCallbacks
    def transform(bldr):
        time = yield bldr.getOldestRequestTime()
        if time is None:
            time = max_time
        else:
            if bldr.name in builder_bonuses:
                time = time + builder_bonuses[bldr.name]
        defer.returnValue((time, bldr))

    transformed = yield defer.gatherResults(
        [transform(bldr) for bldr in builders])

    # sort the transformed list synchronously, comparing None to the end of
    # the list
    def transformedKey(a):
        (date, builder) = a
        return (date, builder.name)

    transformed.sort(key=transformedKey)

    # and reverse the transform
    rv = [xf[1] for xf in transformed]
    return rv

  c['prioritizeBuilders'] = BuilderSorter