apache · tvalentyn · Aug 30, 2025 · Jul 29, 2025 · Jul 29, 2025 · Jul 31, 2025
diff --git a/.github/trigger_files/beam_PostCommit_Python_ValidatesRunner_Dataflow.json b/.github/trigger_files/beam_PostCommit_Python_ValidatesRunner_Dataflow.json
@@ -1,3 +1,4 @@
 {
-  "https://github.com/apache/beam/pull/35951": "triggering sideinput test"
+  "comment": "Modify this file in a trivial way to cause this test suite to run",
+  "modification": 1
 }
diff --git a/sdks/python/apache_beam/coders/coder_impl.pxd b/sdks/python/apache_beam/coders/coder_impl.pxd
@@ -81,13 +81,15 @@ cdef class FastPrimitivesCoderImpl(StreamCoderImpl):
   cdef CoderImpl iterable_coder_impl
   cdef object requires_deterministic_step_label
   cdef bint warn_deterministic_fallback
+  cdef bint force_use_dill
 
   @cython.locals(dict_value=dict, int_value=libc.stdint.int64_t,
                  unicode_value=unicode)
   cpdef encode_to_stream(self, value, OutputStream stream, bint nested)
   @cython.locals(t=int)
   cpdef decode_from_stream(self, InputStream stream, bint nested)
   cdef encode_special_deterministic(self, value, OutputStream stream)
+  cdef encode_type_2_67_0(self, t, OutputStream stream)
   cdef encode_type(self, t, OutputStream stream)
   cdef decode_type(self, InputStream stream)
 

diff --git a/sdks/python/apache_beam/coders/coder_impl.py b/sdks/python/apache_beam/coders/coder_impl.py
@@ -50,14 +50,14 @@
 from typing import Tuple
 from typing import Type
 
-import dill
 import numpy as np
 from fastavro import parse_schema
 from fastavro import schemaless_reader
 from fastavro import schemaless_writer
 
 from apache_beam.coders import observable
 from apache_beam.coders.avro_record import AvroRecord
+from apache_beam.internal import cloudpickle_pickler
 from apache_beam.typehints.schemas import named_tuple_from_schema
 from apache_beam.utils import proto_utils
 from apache_beam.utils import windowed_value
@@ -71,6 +71,11 @@
 except ImportError:
   dataclasses = None  # type: ignore
 
+try:
+  import dill
+except ImportError:
+  dill = None
+
 if TYPE_CHECKING:
   import proto
   from apache_beam.transforms import userstate
@@ -354,14 +359,30 @@ def decode(self, value):
 _ITERABLE_LIKE_TYPES = set()  # type: Set[Type]
 
 
+def _verify_dill_compat():
+  base_error = (
+      "This pipeline runs with the pipeline option "
+      "--update_compatibility_version=2.67.0 or earlier. "
+      "When running with this option on SDKs 2.68.0 or "
+      "later, you must ensure dill==0.3.1.1 is installed.")
+  if not dill:
+    raise RuntimeError(base_error + ". Dill is not installed.")
+  if dill.__version__ != "0.3.1.1":
+    raise RuntimeError(base_error + f". Found dill version '{dill.__version__}")
+
+
 class FastPrimitivesCoderImpl(StreamCoderImpl):
   """For internal use only; no backwards-compatibility guarantees."""
   def __init__(
-      self, fallback_coder_impl, requires_deterministic_step_label=None):
+      self,
+      fallback_coder_impl,
+      requires_deterministic_step_label=None,
+      force_use_dill=False):
     self.fallback_coder_impl = fallback_coder_impl
     self.iterable_coder_impl = IterableCoderImpl(self)
     self.requires_deterministic_step_label = requires_deterministic_step_label
     self.warn_deterministic_fallback = True
+    self.force_use_dill = force_use_dill
 
   @staticmethod
   def register_iterable_like_type(t):
@@ -525,10 +546,23 @@ def _deterministic_encoding_error_msg(self, value):
         "please provide a type hint for the input of '%s'" %
         (value, type(value), self.requires_deterministic_step_label))
 
-  def encode_type(self, t, stream):
+  def encode_type_2_67_0(self, t, stream):
+    """
+    Encode special type with <=2.67.0 compatibility.
+    """
+    _verify_dill_compat()
     stream.write(dill.dumps(t), True)
 
+  def encode_type(self, t, stream):
+    if self.force_use_dill:
+      return self.encode_type_2_67_0(t, stream)
+    bs = cloudpickle_pickler.dumps(
+        t, config=cloudpickle_pickler.NO_DYNAMIC_CLASS_TRACKING_CONFIG)
+    stream.write(bs, True)
+
   def decode_type(self, stream):
+    if self.force_use_dill:
+      return _unpickle_type_2_67_0(stream.read_all(True))
     return _unpickle_type(stream.read_all(True))
 
   def decode_from_stream(self, stream, nested):
@@ -589,19 +623,35 @@ def decode_from_stream(self, stream, nested):
 _unpickled_types = {}  # type: Dict[bytes, type]
 
 
-def _unpickle_type(bs):
+def _unpickle_type_2_67_0(bs):
+  """
+  Decode special type with <=2.67.0 compatibility.
+  """
   t = _unpickled_types.get(bs, None)
   if t is None:
+    _verify_dill_compat()
     t = _unpickled_types[bs] = dill.loads(bs)
     # Fix unpicklable anonymous named tuples for Python 3.6.
     if t.__base__ is tuple and hasattr(t, '_fields'):
       try:
         pickle.loads(pickle.dumps(t))
       except pickle.PicklingError:
-        t.__reduce__ = lambda self: (_unpickle_named_tuple, (bs, tuple(self)))
+        t.__reduce__ = lambda self: (
+            _unpickle_named_tuple_2_67_0, (bs, tuple(self)))
   return t
 
 
+def _unpickle_named_tuple_2_67_0(bs, items):
+  return _unpickle_type_2_67_0(bs)(*items)
+
+
+def _unpickle_type(bs):
+  if not _unpickled_types.get(bs, None):
+    _unpickled_types[bs] = cloudpickle_pickler.loads(bs)
+
+  return _unpickled_types[bs]
+
+
 def _unpickle_named_tuple(bs, items):
   return _unpickle_type(bs)(*items)
 
@@ -837,6 +887,7 @@ def decode_from_stream(self, in_, nested):
       if IntervalWindow is None:
         from apache_beam.transforms.window import IntervalWindow
     # instantiating with None is not part of the public interface
+    # pylint: disable=too-many-function-args
     typed_value = IntervalWindow(None, None)  # type: ignore[arg-type]
     typed_value._end_micros = (
         1000 * self._to_normal_time(in_.read_bigendian_uint64()))

diff --git a/sdks/python/apache_beam/coders/coders.py b/sdks/python/apache_beam/coders/coders.py
@@ -911,6 +911,44 @@ def _create_impl(self):
         cloudpickle_pickler.dumps, cloudpickle_pickler.loads)
 
 
+class DeterministicFastPrimitivesCoderV2(FastCoder):
+  """Throws runtime errors when encoding non-deterministic values."""
+  def __init__(self, coder, step_label):
+    self._underlying_coder = coder
+    self._step_label = step_label
+
+  def _create_impl(self):
+
+    return coder_impl.FastPrimitivesCoderImpl(
+        self._underlying_coder.get_impl(),
+        requires_deterministic_step_label=self._step_label,
+        force_use_dill=False)
+
+  def is_deterministic(self):
+    # type: () -> bool
+    return True
+
+  def is_kv_coder(self):
+    # type: () -> bool
+    return True
+
+  def key_coder(self):
+    return self
+
+  def value_coder(self):
+    return self
+
+  def to_type_hint(self):
+    return Any
+
+  def to_runner_api_parameter(self, context):
+    # type: (Optional[PipelineContext]) -> Tuple[str, Any, Sequence[Coder]]
+    return (
+        python_urns.PICKLED_CODER,
+        google.protobuf.wrappers_pb2.BytesValue(value=serialize_coder(self)),
+        ())
+
+
 class DeterministicFastPrimitivesCoder(FastCoder):
   """Throws runtime errors when encoding non-deterministic values."""
   def __init__(self, coder, step_label):
@@ -920,7 +958,8 @@ def __init__(self, coder, step_label):
   def _create_impl(self):
     return coder_impl.FastPrimitivesCoderImpl(
         self._underlying_coder.get_impl(),
-        requires_deterministic_step_label=self._step_label)
+        requires_deterministic_step_label=self._step_label,
+        force_use_dill=True)
 
   def is_deterministic(self):
     # type: () -> bool
@@ -940,6 +979,34 @@ def to_type_hint(self):
     return Any
 
 
+def _should_force_use_dill():
+  from apache_beam.coders import typecoders
+  from apache_beam.transforms.util import is_v1_prior_to_v2
+  update_compat_version = typecoders.registry.update_compatibility_version
+
+  if not update_compat_version:
+    return False
+
+  if not is_v1_prior_to_v2(v1=update_compat_version, v2="2.68.0"):
+    return False
+
+  try:
+    import dill
+    assert dill.__version__ == "0.3.1.1"
+  except Exception as e:
+    raise RuntimeError("This pipeline runs with the pipeline option " \
+    "--update_compatibility_version=2.67.0 or earlier. When running with " \
+    "this option on SDKs 2.68.0 or later, you must ensure dill==0.3.1.1 " \
+    f"is installed. Error {e}")
+  return True
+
+
+def _update_compatible_deterministic_fast_primitives_coder(coder, step_label):
+  if _should_force_use_dill():
+    return DeterministicFastPrimitivesCoder(coder, step_label)
+  return DeterministicFastPrimitivesCoderV2(coder, step_label)
+
+
 class FastPrimitivesCoder(FastCoder):
   """Encodes simple primitives (e.g. str, int) efficiently.
 
@@ -960,7 +1027,8 @@ def as_deterministic_coder(self, step_label, error_message=None):
     if self.is_deterministic():
       return self
     else:
-      return DeterministicFastPrimitivesCoder(self, step_label)
+      return _update_compatible_deterministic_fast_primitives_coder(
+          self, step_label)
 
   def to_type_hint(self):
     return Any