[WIP] fix(api_core): configure default max_metadata_size in gRPC helpers

[ohmayr]

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Fixes #<issue_number_goes_here> 🦕

[gemini-code-assist]

Code Review

This pull request configures a default grpc.max_metadata_size of 32768 when creating secure gRPC channels in both synchronous and asynchronous helpers, and adds corresponding tests. The reviewer noted that the default limit is currently only applied if custom options are already present in kwargs. To ensure the limit is always enforced, the reviewer suggested initializing options as an empty list when omitted, and provided updated test cases to verify both scenarios.

[gemini-code-assist]

The current implementation only configures grpc.max_metadata_size if options is already present in kwargs. This means that for the default case where no custom options are provided, the default max_metadata_size will not be set. To ensure that the default limit is always configured, we should initialize options as an empty list if it is not provided.

Suggested change

	if "options" in kwargs and isinstance(kwargs["options"], (list, tuple)):
	opts = list(kwargs["options"])
	if not any(
	isinstance(opt, (list, tuple))
	and len(opt) >= 2
	and opt[0] == "grpc.max_metadata_size"
	for opt in opts
	):
	opts.append(("grpc.max_metadata_size", 32768))
	kwargs["options"] = opts
	options = kwargs.get("options")
	if options is None:
	options = []
	elif isinstance(options, (list, tuple)):
	options = list(options)
	else:
	options = None
	if options is not None:
	if not any(
	isinstance(opt, (list, tuple))
	and len(opt) >= 2
	and opt[0] == "grpc.max_metadata_size"
	for opt in options
	):
	options.append(("grpc.max_metadata_size", 32768))
	kwargs["options"] = options

[gemini-code-assist]

The current implementation only configures grpc.max_metadata_size if options is already present in kwargs. This means that for the default case where no custom options are provided, the default max_metadata_size will not be set. To ensure that the default limit is always configured, we should initialize options as an empty list if it is not provided.

Suggested change

	if "options" in kwargs and isinstance(kwargs["options"], (list, tuple)):
	opts = list(kwargs["options"])
	if not any(
	isinstance(opt, (list, tuple))
	and len(opt) >= 2
	and opt[0] == "grpc.max_metadata_size"
	for opt in opts
	):
	opts.append(("grpc.max_metadata_size", 32768))
	kwargs["options"] = opts
	options = kwargs.get("options")
	if options is None:
	options = []
	elif isinstance(options, (list, tuple)):
	options = list(options)
	else:
	options = None
	if options is not None:
	if not any(
	isinstance(opt, (list, tuple))
	and len(opt) >= 2
	and opt[0] == "grpc.max_metadata_size"
	for opt in options
	):
	options.append(("grpc.max_metadata_size", 32768))
	kwargs["options"] = options

[gemini-code-assist]

Update the test to verify that grpc.max_metadata_size is correctly configured both when custom options are provided and when they are omitted.

Suggested change

	def test_create_channel_max_metadata_size(grpc_secure_channel, auth_default):
	options = [("grpc.max_send_message_length", -1)]
	grpc_helpers_async.create_channel("example.com:443", options=options)
	_, kwargs = grpc_secure_channel.call_args
	assert ("grpc.max_metadata_size", 32768) in kwargs["options"]
	def test_create_channel_max_metadata_size(grpc_secure_channel, auth_default):
	options = [("grpc.max_send_message_length", -1)]
	grpc_helpers_async.create_channel("example.com:443", options=options)
	_, kwargs = grpc_secure_channel.call_args
	assert ("grpc.max_metadata_size", 32768) in kwargs["options"]
	grpc_secure_channel.reset_mock()
	grpc_helpers_async.create_channel("example.com:443")
	_, kwargs = grpc_secure_channel.call_args
	assert ("grpc.max_metadata_size", 32768) in kwargs["options"]

[gemini-code-assist]

Update the test to verify that grpc.max_metadata_size is correctly configured both when custom options are provided and when they are omitted.

Suggested change

	def test_create_channel_max_metadata_size(grpc_secure_channel, auth_default):
	options = [("grpc.max_send_message_length", -1)]
	grpc_helpers.create_channel("example.com:443", options=options)
	_, kwargs = grpc_secure_channel.call_args
	assert ("grpc.max_metadata_size", 32768) in kwargs["options"]
	def test_create_channel_max_metadata_size(grpc_secure_channel, auth_default):
	options = [("grpc.max_send_message_length", -1)]
	grpc_helpers.create_channel("example.com:443", options=options)
	_, kwargs = grpc_secure_channel.call_args
	assert ("grpc.max_metadata_size", 32768) in kwargs["options"]
	grpc_secure_channel.reset_mock()
	grpc_helpers.create_channel("example.com:443")
	_, kwargs = grpc_secure_channel.call_args
	assert ("grpc.max_metadata_size", 32768) in kwargs["options"]