pokerlib

A lightweight Python poker library, focusing on simplifying a Texas hold'em poker game implementation, when its io is supplied. It includes modules that help with hand parsing and poker game continuation.

To install, run

pip install pokerlib

If experiencing issues, specify the latest version as

pip install pokerlib==2.2.7

Usage

Library consists of a module for parsing cards, which can be used separately, and modules that aid in running a poker game.

HandParser

This module takes care of hand parsing. A hand usually consists of 2 dealt cards plus 5 on the board, and HandParser is heavily optimized to work with up to 7 cards (with more than 7 cards, this is no longer Texas hold'em). A card is defined as a pair of two enums - Rank and Suit. All of the enums used are of IntEnum type, so you can also freely interchange them for integers. Below is an example of how to construct two different hands and then compare them.

from pokerlib import HandParser
from pokerlib.enums import Rank, Suit

hand1 = HandParser([
    (Rank.KING, Suit.SPADE),
    (Rank.ACE, Suit.SPADE)
])

hand2 = HandParser([
    (Rank.NINE, Suit.SPADE),
    (Rank.TWO, Suit.CLUB)
])

board = [
    (Rank.EIGHT, Suit.SPADE),
    (Rank.TEN, Suit.SPADE),
    (Rank.JACK, Suit.SPADE),
    (Rank.QUEEN, Suit.SPADE),
    (Rank.TWO, Suit.HEART)
]

# add new cards to each hand
hand1 += board # add the board to hand1
hand2 += board # add the board to hand2

print(hand1.handenum) # Hand.STRAIGHTFLUSH
print(hand2.handenum) # Hand.STRAIGHTFLUSH
print(hand1 > hand2) # True

note: In the previous version, each hand had to be parsed manually with hand.parse(), now calling any of the methods requiring the hand to be parsed, triggers parsing automatically. This only happens once, except if the cards in a given hand change. The only way cards in a hand should change is through the __iadd__ method. If this method is called with hand already parsed, the hand is considered unparsed.

It is also possible to fetch hand's kickers.

hand = HandParser([
    (Rank.TWO, Suit.DIAMOND),
    (Rank.ACE, Suit.CLUB),
    (Rank.TWO, Suit.SPADE),
    (Rank.THREE, Suit.DIAMOND),
    (Rank.TEN, Suit.HEART),
    (Rank.SIX, Suit.HEART),
    (Rank.KING, Suit.CLUB)
])

print(list(hand.kickercards))
# [
#   (<Rank.ACE: 12>, <Suit.CLUB: 1>),
#   (<Rank.KING: 11>, <Suit.CLUB: 1>),
#   (<Rank.TEN: 8>, <Suit.HEART: 3>)
# ]

Using HandParser, we can estimate the probability of a given hand winning the game with given known cards on the table (as implemented in another python cli-app here). We do this by repeatedly random-sampling hands, then averaging the wins. Mathematically, this process converges to the probability by the law of large numbers.

Poker Game

A poker table can be established by providing its configuration. A poker table object responds to given input with appropriate output, which can be customized by overriding the two functions producing it.

from pokerlib import Table, Player, PlayerSeats

# table that prints outputs
class MyTable(Table):
    def publicOut(self, out_id, **kwargs):
        print(out_id, kwargs)
    def privateOut(self, player_id, out_id, **kwargs):
        print(out_id, kwargs)

# define a new table
table = MyTable(
    table_id = 0,
    seats = PlayerSeats([None] * 9),
    buyin = 100,
    small_blind = 5,
    big_blind = 10
)

We could have seated players on the seats inside MyTable constructor, but let's add them to the defined table.

player1 = Player(
    table_id = table.id,
    _id = 1,
    name = 'alice',
    money = table.buyin
)
player2 = Player(
    table_id = table.id,
    _id = 2,
    name = 'bob',
    money = table.buyin
)
# seat player1 at the first seat
table += player1, 0
# seat player2 at the first free seat
table += player2

Communication with the table object is established through specified enums, which can be modified by overriding table's publicIn method. Using enum IO identifiers, we can implement a poker game as shown below.

from pokerlib.enums import RoundPublicInId, TablePublicInId

table.publicIn(player1.id, TablePublicInId.STARTROUND)
table.publicIn(player1.id, RoundPublicInId.CALL)
table.publicIn(player2.id, RoundPublicInId.CHECK)
table.publicIn(player1.id, RoundPublicInId.CHECK)
table.publicIn(player2.id, RoundPublicInId.RAISE, raise_by=50)
table.publicIn(player1.id, RoundPublicInId.CALL)
table.publicIn(player1.id, RoundPublicInId.CHECK)
table.publicIn(player2.id, RoundPublicInId.CHECK)
table.publicIn(player1.id, RoundPublicInId.ALLIN)
table.publicIn(player2.id, RoundPublicInId.CALL)

Wrong inputs are mostly ignored, though they can produce a response, when it seems useful. As noted before, when providing input, the table object responds with output ids (e.g. PLAYERACTIONREQUIRED) along with additional data that depends on the output id. For all possible outputs, check RoundPublicInId and TablePublicInId enums.

A simple command line game, where you respond with enum names, can be implemented simply as in examples/round_simulate.py. Command

python examples/round_simulate.py 3

runs a poker game with 3 players using the terminal as IO. Note that responses are in non-formatted raw form.

Tests

Basic tests for this library are included. You can test HandParser by running

python tests/handparser_reactive.py

and Round with

python tests/round_test.py

Note that HandParser can be fuzz tested against another poker library pokerface with

python tests/handparser_against_pokerface.py

which means it is considered safe. On the other hand, Table may still have some bugs.

License

GNU General Public License v3.0