download_syzygy.py

#!/bin/python3

import os
from itertools import combinations_with_replacement

def tablebase_names(K=6):

    letters = ['', 'Q', 'R', 'B', 'N', 'P']

    # Generate many potential K[] v K[], including all valid ones
    candidates = ['K%svK%s' % (''.join(lhs), ''.join(rhs))
        for N in range(1, K - 1)
            for lhs in combinations_with_replacement(letters, N)
                for rhs in combinations_with_replacement(letters, K - N - 2)]

    # Syzygy does LHS having more pieces first, stronger pieces second
    def valid_filename(name):
        for i, letter in enumerate(letters[1:]):
            name = name.replace(letter, str(9 - i))
        lhs, rhs = name.replace('K', '9').split('v')
        return int(lhs) >= int(rhs) and name != 'KvK'

    all_sizes = list(filter(valid_filename, set(candidates)))
    return [f for f in all_sizes if len(f) == K + 1]

for tablebase in tablebase_names(K=6):

    target = 'http://tablebase.lichess.ovh/tables/standard/6-wdl/%s.rtbw' % (tablebase)
    print ('Getting SRC=%s' % (target))
    os.system('curl %s --output %s.rtbw' % (target, tablebase))

    target = 'http://tablebase.lichess.ovh/tables/standard/6-dtz/%s.rtbz' % (tablebase)
    print ('Getting SRC=%s' % (target))
    os.system('curl %s --output %s.rtbz' % (target, tablebase))

for K in [3, 4, 5]:

    for tablebase in tablebase_names(K=K):

        target = 'http://tablebase.lichess.ovh/tables/standard/3-4-5/%s.rtbw' % (tablebase)
        print ('Getting SRC=%s' % (target))
        os.system('curl %s --output %s.rtbw' % (target, tablebase))

        target = 'http://tablebase.lichess.ovh/tables/standard/3-4-5/%s.rtbz' % (tablebase)
        print ('Getting SRC=%s' % (target))
        os.system('curl %s --output %s.rtbz' % (target, tablebase))