Add recursion depth limit to TProtocol.skip() in Python#3411
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Client: py C++ and Go already enforce a limit of 64 recursive skip() calls via TInputRecursionTracker and maxDepth respectively. This change adds an equivalent max_depth=64 parameter to the Python skip() implementation in TProtocolBase, raising TProtocolException(DEPTH_LIMIT) when the limit is exceeded. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
mhlakhani
approved these changes
Apr 22, 2026
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Summary
TProtocolBase.skip()in Python had no recursion depth limit. When deserializing an unknown field, generated code callsskip(), which recursively calls itself for each nested container or struct element. C++, Go, and Node.js all cap this recursion at 64 levels and raise a protocol exception when the limit is exceeded.This change brings Python into parity:
lib/py/src/protocol/TProtocol.py:skip()gains an optionalmax_depthparameter (default 64). At the start of each call, ifmax_depth <= 0aTProtocolException(DEPTH_LIMIT)is raised. All recursive calls passmax_depth - 1.Tests added in
lib/py/test/thrift_TBinaryProtocol.py:test_skip_rejects_deeply_nested_struct: a payload with 64 levels of nesting raisesDEPTH_LIMIT.test_skip_accepts_struct_within_depth_limit: a payload with 63 levels succeeds.Test plan
python3 lib/py/test/thrift_TBinaryProtocol.py -v— two new skip depth tests pass🤖 Generated with Claude Code