Sample
Exclude or include fields across nested collections in Pydantic model serialization using '__all__' rather than bare field names
sha256:be1293698e1116d9918fa867565f81413664583834ba6c5f54bd1d226f885e5b
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Execution evidence
Declared environment and signed verification runs are separated so you can see exactly what this sample proves.
Evidence basisSigned contract pass
Verification receipts1
Verification levelL3_CONTRACT_PASS
Declared environment
- Execution context
- python
- Operating system
- linux
- Architecture
- x64
- Runtime
- python
- Language
- python
- Package manager
- pip
Verification-run environments
- Execution context
- python 3.12
- Operating system
- linux alpine · musl
- Architecture
- x64
- Runtime
- python 3.12
- Language
- python
- Package manager
- pip
- Execution
- container · docker
CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-17
Case
- Goal
- Exclude or include fields across nested collections in Pydantic model serialization using '__all__' rather than bare field names HOW
- Packages
-
pydantic 2.13.4
- Environment
- python
- Created
- 2026-08-17T06:46:46Z
Commonly assumed
Passing a set of field names like {'members': {'secret'}} to model_dump(exclude=...) excludes that field from each nested model in a sequence.
The sample's author recorded this as what a developer or model would expect here. The contract below is what actually ran.
Contract
- Passing a bare field set like {'members': {'secret'}} to model_dump(exclude=...) silently leaves secrets present in nested sequence elements because collection keys represent item indices rather than attribute names.
- Using {'__all__': {'secret'}} under a sequence or mapping key excludes the field from every nested model item.
- Passing integer indices like {0: {'secret'}} under a sequence key excludes fields exclusively from the matching item position.
- Passing bare field names to model_dump(include=...) on a sequence matches zero item indices and returns an empty list, whereas '__all__' projects the requested fields for all items.
- Under mapping fields, bare keys match only exact dictionary keys rather than value attributes unless '__all__' or an explicit mapping key is provided.
Files
- NOTES.md
- csx.json
- requirements.lock
- requirements.txt
- src/__init__.py
- src/models.py
- test/contract.py
Download the source artifact (tar.gz)
Origin Seeder
csx-seed
Verification receipts
- python 3.12 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-17 · ed25519:d91480838ac982c9