decompress .pgn.zst dataset

ChessBot-Dataset.py

@@ -1,3 +1,4 @@
+import io
 import logging
 from datasets import (
     GeneratorBasedBuilder,
@@ -10,6 +11,9 @@ from datasets import (
     Array2D,
 )
 from adversarial_gym.chess_env import ChessEnv
+import zstandard as zstd
+
+
 
 class ChessPGNDataset(GeneratorBasedBuilder):
     VERSION = "0.0.1"
@@ -55,19 +59,23 @@ class ChessPGNDataset(GeneratorBasedBuilder):
         uid = 0
 
         for path in shards:
-            with open(path, "r") as f:
-                while (game := chess.pgn.read_game(f)) is not None:
-                    board = game.board()
-                    base = {"1-0":1,"0-1":-1}.get(game.headers["Result"], 0)
-                    for move in game.mainline_moves():
-                        state  = ChessEnv.get_piece_configuration(board)
-                        state  = state if board.turn else -state
-                        action = ChessEnv.move_to_action(move)
-                        result = base * (-1 if board.turn == 0 else 1)
-                        yield uid, {
-                            "state":  state.astype("int8"),
-                            "action": int(action),
-                            "result": int(result),
-                        }
-                        uid += 1
-                        board.push(move)
+            decompressor = zstd.ZstdDecompressor()
+            with open(path, "rb") as compressed:
+                with decompressor.stream_reader(compressed) as reader:
+                    text_stream = io.TextIOWrapper(reader, encoding='utf-8')
+                    while (game := chess.pgn.read_game(text_stream)) is not None:
+                    # while (game := chess.pgn.read_game(f)) is not None:
+                        board = game.board()
+                        base = {"1-0":1,"0-1":-1}.get(game.headers["Result"], 0)
+                        for move in game.mainline_moves():
+                            state  = ChessEnv.get_piece_configuration(board)
+                            state  = state if board.turn else -state
+                            action = ChessEnv.move_to_action(move)
+                            result = base * (-1 if board.turn == 0 else 1)
+                            yield uid, {
+                                "state":  state.astype("int8"),
+                                "action": int(action),
+                                "result": int(result),
+                            }
+                            uid += 1
+                            board.push(move)