OpenAPI allows description of "additionalProperties" that may be included in a schema. Their names are unknown, but the field types can be added to the API description. Producers and consumers then understand whether additional fields are permitted and any additional rules that apply.
Since the field names are not specified, they are displayed with a generic name in the API reference documentation. Use x-additionalProperties to display a more meaningful name in this scenario.
Use x-additionalPropertiesName as a property of additionaProperties in an OpenAPI Schema.
| Option | Type | Description |
|---|---|---|
| x-additionalPropertiesName | string | Add a display name for an additionalProperty. By default it shows as property name*. |
The following example shows a schema for a set of sensors reporting fill levels. The schema accepts any fields as long as the values are numbers between 0-100:
components:
schemas:
FillLevel:
type: object
properties:
reportTime:
type: string
format: date-time
description: Report creation time.
required:
- reportTime
additionalProperties:
x-additionalPropertiesName: percentage
type: integer
minimum: 0
maximum: 100The additional properties appear in the documentation as percentage*.
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