KUBB_UNSUPPORTED_FORMAT: Unsupported format
The KUBB_UNSUPPORTED_FORMAT diagnostic fires when a schema uses a format Kubb does not map to a specific type.
Code: KUBB_UNSUPPORTED_FORMAT Level: warning
A schema's format is not one Kubb maps to a specific type, so it falls back to the base type.
What happened
While walking the named component schemas, the OpenAPI adapter found a format it has no specific mapping for. Generation continues with the base type, for example string. This is a warning, not a failure. The adapter reports it on every run.
How to fix it
- Use a format Kubb supports, or drop the
formatif the base type is enough. - Handle the custom format with a parser or plugin that maps it to the type you want.
Common causes
- A vendor-specific format such as
snowflakeormoneythat has no built-in mapping. - A typo in a standard format, such as
date-tineinstead ofdate-time.
Example
petStore.yaml
components: schemas: Pet: type: object properties: id: type: string format: snowflake # falls back to stringExample output
Terminal
[KUBB_UNSUPPORTED_FORMAT]: Kubb does not map the format "snowflake" to a specific type, so it falls back to the base type. at: #/components/schemas/Pet/properties/id fix: Use a format Kubb supports, or handle "snowflake" with a custom parser or plugin. see: https://kubb.dev/docs/5.x/reference/diagnostics/kubb-unsupported-format