python(bug): decode large flow schemas on stream build

python/CHANGELOG.md

@@ -7,6 +7,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Bugfixes
 - Fix `assets.archive` raising `AttributeError` by reading the correct response field, `archived_run_ids`.
+- Fix streaming ingestion failing to start when an ingestion config's flow schema exceeded the streaming client's 4 MiB decode limit. `sift-stream-bindings` 0.5.0 decodes up to 50 MiB.
 
 ## [v0.19.1] - July 27, 2026
 

python/lib/sift_client/_internal/grpc_transport/transport.py

@@ -34,6 +34,9 @@
 DEFAULT_REQUEST_TIMEOUT_SECONDS = 60.0
 """Default per-call deadline applied to unary RPCs that don't set their own."""
 
+MAX_DECODING_MESSAGE_SIZE = 50 * 1024 * 1024
+"""Largest gRPC response the client will decode, in bytes (50 MiB)."""
+
 
 def get_ssl_credentials(cert_via_openssl: bool) -> grpc.ChannelCredentials:
     """
@@ -165,10 +168,7 @@ def _compute_channel_options(opts: SiftChannelConfig) -> list[tuple[str, Any]]:
         # Primary cannot be overriden:
         #  https://github.com/grpc/grpc/blob/0498194240f55d7f4b12633ad01339fb690621bf/src/core/ext/filters/http/client/http_client_filter.cc#L97
         ("grpc.secondary_user_agent", _compute_user_agent()),
-        (
-            "grpc.max_receive_message_length",
-            50 * 1024 * 1024,
-        ),  # 50 MB — headroom for 1M-row GetData pages
+        ("grpc.max_receive_message_length", MAX_DECODING_MESSAGE_SIZE),
     ]
 
     enable_keepalive = opts.get("enable_keepalive", True)

python/lib/sift_client/_internal/pyproject_config.py

@@ -16,7 +16,7 @@
 # ``tomllib`` landed in 3.11; ``tomli`` is the same parser packaged for older
 # interpreters and is declared as a conditional install dep on 3.8-3.10.
 try:
-    import tomllib  # type: ignore[import-not-found,unused-ignore]
+    import tomllib  # type: ignore[import-not-found,import-untyped,unused-ignore]
 except ImportError:  # pragma: no cover - exercised on 3.8-3.10 only
     import tomli as tomllib  # type: ignore[no-redef,import-not-found,unused-ignore]
 

python/lib/sift_client/_tests/_internal/test_transport.py

@@ -4,6 +4,10 @@
 
 import pytest
 
+from sift_client._internal.grpc_transport.transport import (
+    MAX_DECODING_MESSAGE_SIZE,
+    _compute_channel_options,
+)
 from sift_client.transport.grpc_transport import GrpcClient, GrpcConfig
 from sift_client.transport.rest_transport import DEFAULT_REST_TIMEOUT, RestClient, RestConfig
 
@@ -150,3 +154,10 @@ def test_timeout_disabled_when_config_none(self):
         captured = self._capture_request_kwargs(client)
         client.get("/v1/ping")
         assert "timeout" not in captured
+
+
+class TestMaxDecodingMessageSize:
+    def test_channel_uses_the_fixed_limit(self):
+        config = GrpcConfig(url="https://grpc.sift.com", api_key="api")
+        options = dict(_compute_channel_options(config._to_sift_channel_config()))
+        assert options["grpc.max_receive_message_length"] == MAX_DECODING_MESSAGE_SIZE

python/pyproject.toml

@@ -69,7 +69,7 @@ all = [
     'pyarrow>=17.0.0',
     'pyulog~=1.2.2',
     "rosbags~=0.0 ; python_full_version >= '3.8.2'",
-    'sift-stream-bindings==0.4.1',
+    'sift-stream-bindings==0.5.0',
     'types-pyOpenSSL<24.0.0',
 ]
 build = [
@@ -115,7 +115,7 @@ dev-all = [
     'pyulog~=1.2.2',
     "rosbags~=0.0 ; python_full_version >= '3.8.2'",
     'ruff~=0.12.10',
-    'sift-stream-bindings==0.4.1',
+    'sift-stream-bindings==0.5.0',
     'tomlkit~=0.13.3',
     'types-pyOpenSSL<24.0.0',
 ]
@@ -173,7 +173,7 @@ docs-build = [
     'pyulog~=1.2.2',
     "rosbags~=0.0 ; python_full_version >= '3.8.2'",
     'ruff~=0.12.10',
-    'sift-stream-bindings==0.4.1',
+    'sift-stream-bindings==0.5.0',
     'tomlkit~=0.13.3',
     'types-pyOpenSSL<24.0.0',
 ]
@@ -197,10 +197,10 @@ rosbags = [
     "rosbags~=0.0 ; python_full_version >= '3.8.2'",
 ]
 sift-stream = [
-    'sift-stream-bindings==0.4.1',
+    'sift-stream-bindings==0.5.0',
 ]
 sift-stream-bindings = [
-    'sift-stream-bindings==0.4.1',
+    'sift-stream-bindings==0.5.0',
 ]
 tdms = [
     'npTDMS~=1.9',
@@ -248,7 +248,7 @@ docs = [
 openssl = ["pyOpenSSL<24.0.0", "types-pyOpenSSL<24.0.0", "cffi~=1.14"]
 tdms = ["npTDMS~=1.9"]
 rosbags = ["rosbags~=0.0 ; python_full_version >= '3.8.2'"]
-sift-stream = ["sift-stream-bindings==0.4.1"]
+sift-stream = ["sift-stream-bindings==0.5.0"]
 hdf5 = ["h5py~=3.11", "polars~=1.8"]  # polars is only used by sift_py; remove once sift_py is fully deprecated
 ulog = ["pyulog~=1.2.2"]
 data-review = ["pyarrow>=17.0.0"]