Deprecate hashregister API

Author: mariosasko

src/datasets/fingerprint.py

@@ -1,5 +1,4 @@
 import inspect
-import json
 import os
 import random
 import shutil
@@ -10,18 +9,12 @@
 from typing import TYPE_CHECKING, Any, Callable, Dict, List, Optional, Tuple, Union
 
 import numpy as np
-import pyarrow as pa
 import xxhash
 
-from .info import DatasetInfo
 from .naming import INVALID_WINDOWS_CHARACTERS_IN_PATH
-from .table import ConcatenationTable, InMemoryTable, MemoryMappedTable, Table
 from .utils._dill import dumps
-
-# from .utils.py_utils import dumps
 from .utils.deprecation_utils import deprecated
 from .utils.logging import get_logger
-from .utils.py_utils import asdict
 
 
 if TYPE_CHECKING:
@@ -202,6 +195,7 @@ def cleanup_func():
 #################
 
 
+@deprecated("Use `copyreg.pickle` to register a custom reducer.")
 def hashregister(*types):
     def proxy(func):
         for t in types:
@@ -228,15 +222,13 @@ def hash_bytes(cls, value: Union[bytes, List[bytes]]) -> str:
         return m.hexdigest()
 
     @classmethod
+    @deprecated("Use `Hasher.hash` instead.")
     def hash_default(cls, value: Any) -> str:
-        return cls.hash_bytes(dumps(value))
+        return cls.hash(value)
 
     @classmethod
     def hash(cls, value: Any) -> str:
-        if type(value) in cls.dispatch:
-            return cls.dispatch[type(value)](cls, value)
-        else:
-            return cls.hash_default(value)
+        return cls.hash_bytes(dumps(value))
 
     def update(self, value: Any) -> None:
         header_for_update = f"=={type(value)}=="
@@ -248,28 +240,6 @@ def hexdigest(self) -> str:
         return self.m.hexdigest()
 
 
-# Register a new hasher can be useful for two possible reasons:
-# 1 - optimize the hashing of large amount of data (e.g. pa.Table)
-# 2 - take advantage of a custom serialization method (e.g. DatasetInfo)
-
-
-@hashregister(pa.Table, Table, InMemoryTable, MemoryMappedTable, ConcatenationTable)
-def _hash_pa_table(hasher, value):
-    def _hash_pa_array(value):
-        if isinstance(value, pa.ChunkedArray):
-            return hasher.hash_bytes(c.to_string().encode("utf-8") for c in value.chunks)
-        else:
-            return hasher.hash_bytes(value.to_string().encode("utf-8"))
-
-    value = "-".join(col + "-" + _hash_pa_array(value[col]) for col in sorted(value.column_names))
-    return hasher.hash_bytes(value.encode("utf-8"))
-
-
-@hashregister(DatasetInfo)
-def _hash_dataset_info(hasher, value):
-    return hasher.hash_bytes(json.dumps(asdict(value), sort_keys=True).encode("utf-8"))
-
-
 #################
 # Fingerprinting
 #################