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InvalidSchemaFormatValue exception when unmarshalling string with format 'byte'

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#261 3 comments 3 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
45/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
openapi, python
Domain
api

Research direction

Start by tracing the unmarshalling path for string values with the OpenAPI byte format and locate the format validation code. Add a regression test using base64.b64encode(b'\xff'); done means binary data that is not valid UTF-8 unmarshals without InvalidSchemaFormatValue.

Written by the indexing model from the issue text.

Description

When validating a property of type

type: string
format: byte

it is assumed that the base64 encoded value can be represented as utf-8 string. As a result InvalidSchemaFormatValue is raised when unmarshalling binary data which can't be represented as utf-8 string, e.g. the value base64.b64encode(b'\xff').

The exception text is:
Failed to format value /w== to format byte: 'utf-8' codec can't decode byte 0xff in position 0: invalid start byte.

Dominant language
Python
Stars
368
Forks
140
No merged PRs in 30d

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