[Bug]: Illegal characters in component keys (Swagger)

[flexwie]

Describe the bug

If you define a component with keys that include a character outside of [A-Z a-z 0-9 - . _] the corresponding key in the OpenAPI definition will contain that character even if its not allowed by swagger (paste result here).

Is there some way to remove the characters from the generated key as a workaround?

Reproduction

https://typespec.io/playground?c=aW1wb3J0ICJAdHlwZXNwZWMvaHR0cCI7CtIZcmVzdNUZb3BlbmFwaTMiOwoKdXNpbmcgVHlwZVNwZWMuSHR0cDsKCgpAc2VydmljZSh7CiAgICB0aXRsZTogIlTEUwp9KQpAcm91dGUoIi8iKQpuYW1lc3BhY2UgRW5kcG9pbnRzIMY3QGdldMYJdGFnKCJsaXN0IinFEW9wIMQOKC4uLkNvbW1vblBhcmFtZXRlcnMpOiBzdHJpbmc7Cn0KCm1vZGVsINAkyGBxdWVyecULJHRha2U%2FOiBpbnQzMjsKfQ%3D%3D&e=%40typespec%2Fopenapi3&options=%7B%7D

Checklist

• Follow our Code of Conduct
• Check that there isn't already an issue that request the same bug to avoid creating a duplicate.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion.
• The provided reproduction is a minimal reproducible example of the bug.

[timotheeguerin]

Hi @flexwie can you show where it says having those are not allowed in swagger? You are talking about the parameter called $take?

I pasted the resulting openapi in editor.swagger.io and there was no issues

[flexwie]

Sorry, it seems like the playground link was not up to date. Please try again with this example:

https://typespec.io/playground?c=aW1wb3J0ICJAdHlwZXNwZWMvaHR0cCI7CtIZcmVzdNUZb3BlbmFwaTMiOwoKdXNpbmcgVHlwZVNwZWMuSHR0cDsKCgpAc2VydmljZSh7CiAgICB0aXRsZTogIlTEUwp9KQpAcm91dGUoIi8iKQpuYW1lc3BhY2UgRW5kcG9pbnRzIMY3QGdldMYJdGFnKCJsaXN0IinFEW9wIMQOKC4uLkNvbW1vblBhcmFtZXRlcnMpOiBzdHJpbmc7Cn0KCm1vZGVsINAkyGBxdWVyecULJHRha2U%2FOiBpbnQzMjvSHm9wyh19&e=%40typespec%2Fopenapi3&options=%7B%7D

[wanlwanl]

OAS3 emitter should follow https://datatracker.ietf.org/doc/html/rfc3986#section-2.2 to validate the characters

[wanlwanl]

@skywing918

[skywing918]

All the fixed fields declared above are objects that MUST use keys that match the regular expression: ^[a-zA-Z0-9.-_]+$.

Field Name Examples:

User
User_1
User_Name
user-name
my.org.User