~ in place of a schema name says that the contract does not describe the body: the provider promises no structure, and the consumer reads nothing from it. A status left without a value, such as 204:, is the same ~, since YAML reads both as null. Write ~ for a response without a body, and for every body that is a file or a multipart form, in a request or a response:
yaml
provides: rest: /pets/*: delete: responses: 204: /files/*: get: responses: 200: ~ /files: post: request: ~ responses: 201: File
The resource still exists, so a consumer that calls DELETE /pets/* matches it. Nothing inside the body is compared, and ~ does not tell a body that is empty from a body that is not described. Against a counterpart:
| Provider | Consumer | Result |
|---|---|---|
200: ~ | 200: ~ | compatible |
200: Pet | 200: ~ | compatible |
200: ~ | 200: Pet | break: Pet — petstore_web reads it, but petstore_api doesn't provide it, at the body |
request: ~ | request: NewFile | compatible |
no request | request: NewFile | break: petstore_web sends a request body, but petstore_api declares none |
An empty string is not ~: 204: "" and request: "" name a schema called "", which no schema declares, and are rejected.